-> v0.24.3

Merge pull request #525 from nolanlawson/nolan/sw-index-html
add service-worker-index.html
2026-01-13 11:35:28 +00:00 · 2019-02-01 05:40:58 -05:00 · 2019-02-01 05:36:08 -05:00 · 2019-02-01 05:34:20 -05:00 · 2018-12-31 11:46:08 -05:00 · 2018-12-31 11:45:20 -05:00
295 changed files with 17387 additions and 312 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,15 @@
 .DS_Store
-node_modules
+yarn.lock
+yarn-error.log
+node_modules
+cypress/screenshots
+test/app/.sapper
+test/app/src/manifest
+__sapper__
+test/app/export
+test/app/build
+sapper
+runtime.js
+dist
+!rollup.config.js
+templates/*.js
--- a/.travis.yml
+++ b/.travis.yml
@@ -0,0 +1,21 @@
+sudo: false
+
+language: node_js
+
+node_js:
+  - "6"
+  - "stable"
+
+env:
+  global:
+    - BUILD_TIMEOUT=10000
+
+addons:
+  apt:
+    packages:
+      - xvfb
+
+install:
+  - export DISPLAY=':99.0'
+  - Xvfb :99 -screen 0 1024x768x24 > /dev/null 2>&1 &
+  - npm ci || npm i
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -0,0 +1,581 @@
+# sapper changelog
+
+## 0.24.3
+
+* Add service-worker-index.html shell file for offline support ([#422](https://github.com/sveltejs/sapper/issues/422))
+* Don't cache .map files ([#534](https://github.com/sveltejs/sapper/issues/534))
+
+## 0.24.2
+
+* Support Rollup 1.0 ([#541](https://github.com/sveltejs/sapper/pull/541))
+
+## 0.24.1
+
+* Include CSS chunks in webpack build info to avoid duplication ([#529](https://github.com/sveltejs/sapper/pull/529))
+* Fix preload `as` for styles ([#530](https://github.com/sveltejs/sapper/pull/530))
+
+## 0.24.0
+
+* Handle external URLs in `this.redirect` ([#490](https://github.com/sveltejs/sapper/issues/490))
+* Strip leading `/` from basepath ([#495](https://github.com/sveltejs/sapper/issues/495))
+* Treat duplicate query string parameters as arrays ([#497](https://github.com/sveltejs/sapper/issues/497))
+* Don't buffer `stdout` and `stderr` ([#305](https://github.com/sveltejs/sapper/issues/305))
+* Posixify `build_dir` ([#498](https://github.com/sveltejs/sapper/pull/498))
+* Use `page[XY]Offset` instead of `scroll[XY]` ([#480](https://github.com/sveltejs/sapper/issues/480))
+
+## 0.23.5
+
+* Include lazily-imported CSS in main CSS chunk ([#492](https://github.com/sveltejs/sapper/pull/492))
+* Make search param decoding spec-compliant ([#493](https://github.com/sveltejs/sapper/pull/493))
+* Handle async route errors ([#488](https://github.com/sveltejs/sapper/pull/488))
+
+## 0.23.4
+
+* Ignore empty anchors when exporting ([#491](https://github.com/sveltejs/sapper/pull/491))
+
+## 0.23.3
+
+* Clear `error` and `status` on successful render ([#477](https://github.com/sveltejs/sapper/pull/477))
+
+## 0.23.2
+
+* Fix entry point CSS ([#471](https://github.com/sveltejs/sapper/pull/471))
+
+## 0.23.1
+
+* Scroll to deeplink that matches current URL ([#472](https://github.com/sveltejs/sapper/pull/472))
+* Scroll to deeplink on another page ([#341](https://github.com/sveltejs/sapper/issues/341))
+
+## 0.23.0
+
+* Overhaul internal APIs ([#468](https://github.com/sveltejs/sapper/pull/468))
+* Remove unused `sapper start` and `sapper upgrade` ([#468](https://github.com/sveltejs/sapper/pull/468))
+* Remove magic environment variables ([#469](https://github.com/sveltejs/sapper/pull/469))
+* Preserve SSI comments ([#470](https://github.com/sveltejs/sapper/pull/470))
+
+## 0.22.10
+
+* Handle `sapper-noscroll` attribute on `<a>` elements ([#376](https://github.com/sveltejs/sapper/issues/376))
+* Fix CSS paths when using a base path ([#466](https://github.com/sveltejs/sapper/pull/466))
+
+## 0.22.9
+
+* Fix legacy builds ([#462](https://github.com/sveltejs/sapper/pull/462))
+
+## 0.22.8
+
+* Ensure CSS placeholders are overwritten ([#462](https://github.com/sveltejs/sapper/pull/462))
+
+## 0.22.7
+
+* Fix cookies ([#460](https://github.com/sveltejs/sapper/pull/460))
+
+## 0.22.6
+
+* Normalise chunk filenames on Windows ([#456](https://github.com/sveltejs/sapper/pull/456))
+* Load modules with credentials ([#458](https://github.com/sveltejs/sapper/pull/458))
+
+## 0.22.5
+
+* Fix `sapper dev`. Oops.
+
+## 0.22.4
+
+* Ensure launcher does not overwrite a module ([#455](https://github.com/sveltejs/sapper/pull/455))
+
+## 0.22.3
+
+* Prevent server from accidentally importing dev client
+
+## 0.22.2
+
+* Make paths in generated code relative to project
+
+## 0.22.1
+
+* Fix `pkg.files`
+
+## 0.22.0
+
+* Move generated files into `__sapper__` ([#453](https://github.com/sveltejs/sapper/pull/453))
+* Change default build and export directories to `__sapper__/build` and `__sapper__/export` ([#453](https://github.com/sveltejs/sapper/pull/453))
+
+## 0.21.1
+
+* Read template from build directory in production
+
+## 0.21.0
+
+* Change project folder structure ([#432](https://github.com/sveltejs/sapper/issues/432))
+* Escape filenames ([#446](https://github.com/sveltejs/sapper/pull/446/))
+
+## 0.20.4
+
+* Fix legacy build CSS ([#439](https://github.com/sveltejs/sapper/issues/439))
+* Enable debugging in Chrome and VSCode ([#435](https://github.com/sveltejs/sapper/issues/435))
+
+## 0.20.3
+
+* Inject `nonce` attribute if `res.locals.nonce` is present ([#424](https://github.com/sveltejs/sapper/pull/424))
+* Prevent service worker caching ([#428](https://github.com/sveltejs/sapper/pull/428))
+* Consistent caching for HTML responses ([#429](https://github.com/sveltejs/sapper/pull/429))
+
+## 0.20.2
+
+* Add `immutable` cache control header for hashed assets ([#425](https://github.com/sveltejs/sapper/pull/425))
+* Handle value-less query string params ([#426](https://github.com/sveltejs/sapper/issues/426))
+
+## 0.20.1
+
+* Update shimport
+
+## 0.20.0
+
+* Decode `req.params` and `req.query` ([#417](https://github.com/sveltejs/sapper/issues/417))
+* Decode URLs before writing files in `sapper export` ([#414](https://github.com/sveltejs/sapper/pull/414))
+* Generate server sourcemaps for Rollup apps in dev mode ([#418](https://github.com/sveltejs/sapper/pull/418))
+
+## 0.19.3
+
+* Better unicode route handling ([#347](https://github.com/sveltejs/sapper/issues/347))
+
+## 0.19.2
+
+* Ignore editor tmp files ([#220](https://github.com/sveltejs/sapper/issues/220))
+* Ignore clicks an `<a>` element without `href` ([#235](https://github.com/sveltejs/sapper/issues/235))
+* Allow routes that are reserved JavaScript words ([#315](https://github.com/sveltejs/sapper/issues/315))
+* Print out webpack errors ([#403](https://github.com/sveltejs/sapper/issues/403))
+
+## 0.19.1
+
+* Don't include local origin in export redirects ([#409](https://github.com/sveltejs/sapper/pull/409))
+
+## 0.19.0
+
+* Extract styles out of JS into .css files, for Rollup apps ([#388](https://github.com/sveltejs/sapper/issues/388))
+* Fix `prefetchRoutes` ([#380](https://github.com/sveltejs/sapper/issues/380))
+
+## 0.18.7
+
+* Support differential bundling for Rollup apps via a `--legacy` flag ([#280](https://github.com/sveltejs/sapper/issues/280))
+
+## 0.18.6
+
+* Bundle missing dependency
+
+## 0.18.5
+
+* Bugfix
+
+## 0.18.4
+
+* Handle non-Sapper responses when exporting ([#382](https://github.com/sveltejs/sapper/issues/392))
+* Add `--dev-port` flag to `sapper dev` ([#381](https://github.com/sveltejs/sapper/issues/381))
+
+## 0.18.3
+
+* Fix service worker Rollup build config
+
+## 0.18.2
+
+* Update `pkg.files`
+
+## 0.18.1
+
+* Add live reloading ([#385](https://github.com/sveltejs/sapper/issues/385))
+
+## 0.18.0
+
+* Rollup support ([#379](https://github.com/sveltejs/sapper/pull/379))
+* Fail `export` if a page times out (configurable with `--timeout`) ([#378](https://github.com/sveltejs/sapper/pull/378))
+
+## 0.17.1
+
+* Print which file is causing build errors/warnings ([#371](https://github.com/sveltejs/sapper/pull/371))
+
+## 0.17.0
+
+* Use `cheap-watch` instead of `chokidar` ([#364](https://github.com/sveltejs/sapper/issues/364))
+
+## 0.16.1
+
+* Fix file watching regression in previous version
+
+## 0.16.0
+
+* Slim down installed package ([#363](https://github.com/sveltejs/sapper/pull/363))
+
+## 0.15.8
+
+* Only set `preloading: true` on navigation, not prefetch ([#352](https://github.com/sveltejs/sapper/issues/352))
+* Provide fallback for missing preload errors ([#361](https://github.com/sveltejs/sapper/pull/361))
+
+## 0.15.7
+
+* Strip leading slash from redirects ([#291](https://github.com/sveltejs/sapper/issues/291))
+* Pass `(req, res)` to store getter ([#344](https://github.com/sveltejs/sapper/issues/344))
+
+## 0.15.6
+
+* Fix exporting with custom basepath ([#342](https://github.com/sveltejs/sapper/pull/342))
+
+## 0.15.5
+
+* Faster `export` with more explanatory output ([#335](https://github.com/sveltejs/sapper/pull/335))
+* Only blur `activeElement` if it exists ([#332](https://github.com/sveltejs/sapper/issues/332))
+* Don't emit `client_info.json` or `server_info.json` ([#318](https://github.com/sveltejs/sapper/issues/318))
+
+## 0.15.4
+
+* Add `ignore` option ([#326](https://github.com/sveltejs/sapper/pull/326))
+
+## 0.15.3
+
+* Crawl pages in parallel when exporting ([#329](https://github.com/sveltejs/sapper/pull/329))
+* Don't minify inline JS when exporting ([#328](https://github.com/sveltejs/sapper/pull/328))
+
+## 0.15.2
+
+* Collapse component chains where no intermediate layout component is specified ([#312](https://github.com/sveltejs/sapper/issues/312))
+
+## 0.15.1
+
+* Prevent confusing error when no root layout is specified
+
+## 0.15.0
+
+* Nested routes (consult [migration guide](https://sapper.svelte.technology/guide#0-14-to-0-15) and docs on [layouts](https://sapper.svelte.technology/guide#layouts)) ([#262](https://github.com/sveltejs/sapper/issues/262))
+
+## 0.14.2
+
+* Prevent unsafe replacements ([#307](https://github.com/sveltejs/sapper/pull/307))
+
+## 0.14.1
+
+* Route parameters can be qualified with regex characters ([#283](https://github.com/sveltejs/sapper/pull/283))
+
+## 0.14.0
+
+* `4xx.html` and `5xx.html` are replaced with `_error.html` ([#209](https://github.com/sveltejs/sapper/issues/209))
+* Treat `foo/index.json.js` and `foo.json.js` as equivalents ([#297](https://github.com/sveltejs/sapper/issues/297))
+* Return a promise from `goto` ([#270](https://github.com/sveltejs/sapper/issues/270))
+* Use store when rendering error pages ([#293](https://github.com/sveltejs/sapper/issues/293))
+* Prevent console errors when visiting an error page ([#279](https://github.com/sveltejs/sapper/issues/279))
+
+## 0.13.6
+
+* Fix `baseUrl` synthesis ([#296](https://github.com/sveltejs/sapper/issues/296))
+
+## 0.13.5
+
+* Fix handling of fatal errors ([#289](https://github.com/sveltejs/sapper/issues/289))
+
+## 0.13.4
+
+* Focus `<body>` after navigation ([#287](https://github.com/sveltejs/sapper/issues/287))
+* Fix timing of hot reload updates
+* Emit `fatal` event if server crashes ([#285](https://github.com/sveltejs/sapper/pull/285))
+* Emit `stdout` and `stderr` events on dev watcher ([#285](https://github.com/sveltejs/sapper/pull/285))
+* Always refresh client assets in dev ([#286](https://github.com/sveltejs/sapper/pull/286))
+* Correctly initialise rebuild stats
+
+## 0.13.3
+
+* Make `fatal` events clonable for IPC purposes
+
+## 0.13.2
+
+* Emit a `basepath` event ([#284](https://github.com/sveltejs/sapper/pull/284))
+
+## 0.13.1
+
+* Reinstate ten-second interval between dev server heartbeats ([#276](https://github.com/sveltejs/sapper/issues/276))
+
+## 0.13.0
+
+* Expose `dev`, `build`, `export` and `find_page` APIs ([#272](https://github.com/sveltejs/sapper/issues/272))
+
+## 0.12.0
+
+* Each app has a single `<App>` component. See the [migration guide](https://sapper.svelte.technology/guide#0-11-to-0-12) for more information ([#157](https://github.com/sveltejs/sapper/issues/157))
+* Process exits with error code 1 if build/export fails ([#208](https://github.com/sveltejs/sapper/issues/208))
+
+## 0.11.1
+
+* Limit routes with leading dots to `.well-known` URIs ([#252](https://github.com/sveltejs/sapper/issues/252))
+* Allow server routes to sit in front of pages ([#236](https://github.com/sveltejs/sapper/pull/236))
+
+## 0.11.0
+
+* Create launcher file ([#240](https://github.com/sveltejs/sapper/issues/240))
+* Only keep necessary parts of webpack stats ([#251](https://github.com/sveltejs/sapper/pull/251))
+* Allow `NODE_ENV` to be overridden when building ([#241](https://github.com/sveltejs/sapper/issues/241))
+
+## 0.10.7
+
+* Allow routes to have a leading `.` ([#243](https://github.com/sveltejs/sapper/pull/243))
+* Only encode necessary characters in routes ([#234](https://github.com/sveltejs/sapper/pull/234))
+* Preserve existing `process.env` when exporting ([#245](https://github.com/sveltejs/sapper/pull/245))
+
+## 0.10.6
+
+* Fix error reporting in `sapper start`
+
+## 0.10.5
+
+* Fix missing service worker ([#231](https://github.com/sveltejs/sapper/pull/231))
+
+## 0.10.4
+
+* Upgrade chokidar, this time with a fix ([#227](https://github.com/sveltejs/sapper/pull/227))
+
+## 0.10.3
+
+* Downgrade chokidar ([#212](https://github.com/sveltejs/sapper/issues/212))
+
+## 0.10.2
+
+* Attach `store` to error pages
+* Fix sorting edge case ([#215](https://github.com/sveltejs/sapper/pull/215))
+
+## 0.10.1
+
+* Fix server-side `fetch` paths ([#207](https://github.com/sveltejs/sapper/pull/207))
+
+## 0.10.0
+
+* Support mounting on a path (this requires `app/template.html` to include `%sapper.base%`) ([#180](https://github.com/sveltejs/sapper/issues/180))
+* Support per-request server-side `Store` with client-side hydration ([#178](https://github.com/sveltejs/sapper/issues/178))
+* Add `this.fetch` to `preload`, with credentials support ([#178](https://github.com/sveltejs/sapper/issues/178))
+* Exclude sourcemaps from preload links and `<script>` block ([#204](https://github.com/sveltejs/sapper/pull/204))
+* Register service worker in `<script>` block
+
+
+## 0.9.6
+
+* Whoops — `tslib` is a runtime dependency
+
+## 0.9.5
+
+* Stringify clorox output ([#197](https://github.com/sveltejs/sapper/pull/197))
+
+## 0.9.4
+
+* Add `SAPPER_BASE` and `SAPPER_APP` environment variables ([#181](https://github.com/sveltejs/sapper/issues/181))
+* Minify template in `sapper build` ([#15](https://github.com/sveltejs/sapper/issues/15))
+* Minify all HTML files in `sapper export` ([#172](https://github.com/sveltejs/sapper/issues/172))
+* Log exported files ([#195](https://github.com/sveltejs/sapper/pull/195))
+* Add `--open`/`-o` flag to `sapper dev` and `sapper start` ([#186](https://github.com/sveltejs/sapper/issues/186))
+
+## 0.9.3
+
+* Fix path to `sapper-dev-client`
+
+## 0.9.2
+
+* Include `dist` files in package
+
+## 0.9.1
+
+* Include `sapper` bin
+
+## 0.9.0
+
+* Use `devalue` instead of `serialize-javascript`, allowing `preload` to return non-POJOs and cyclical/repeated references, but *not* functions ([#112](https://github.com/sveltejs/sapper/issues/112))
+* Kill child process if webpack crashes ([#177](https://github.com/sveltejs/sapper/issues/177))
+* Support HMR on remote devices ([#165](https://github.com/sveltejs/sapper/issues/165))
+* Remove hard-coded port (([#169](https://github.com/sveltejs/sapper/issues/169)))
+* Allow non-JS files, e.g. TypeScript to be used as entry points and server routes ([#57](https://github.com/sveltejs/sapper/issues/57))
+* Faster startup ([#173](https://github.com/sveltejs/sapper/issues/173))
+
+## 0.8.4
+
+* Fix route sorting ([#175](https://github.com/sveltejs/sapper/pull/175))
+
+## 0.8.3
+
+* Automatically select available port, or use `--port` flag for `dev` and `start` ([#169](https://github.com/sveltejs/sapper/issues/169))
+* Show stats after build/export ([#168](https://github.com/sveltejs/sapper/issues/168))
+* Various CLI improvements ([#170](https://github.com/sveltejs/sapper/pull/170))
+
+## 0.8.2
+
+* Rename `preloadRoutes` to `prefetchRoutes` ([#166](https://github.com/sveltejs/sapper/issues/166))
+
+## 0.8.1
+
+* Add `sapper start` command, for running an app built with `sapper build` ([#163](https://github.com/sveltejs/sapper/issues/163))
+
+## 0.8.0
+
+* Update to webpack 4
+* Add `preloadRoutes` function — secondary routes are no longer automatically preloaded ([#160](https://github.com/sveltejs/sapper/issues/160))
+* `sapper build` outputs to `build`, `sapper build custom-dir` outputs to `custom-dir` ([#150](https://github.com/sveltejs/sapper/pull/150))
+* `sapper export` outputs to `export`, `sapper export custom-dir` outputs to `custom-dir` ([#150](https://github.com/sveltejs/sapper/pull/150))
+* Improved logging ([#158](https://github.com/sveltejs/sapper/pull/158))
+* URI-encode routes ([#103](https://github.com/sveltejs/sapper/issues/103))
+* Various performance and stability improvements ([#152](https://github.com/sveltejs/sapper/pull/152))
+
+## 0.7.6
+
+* Prevent client-side navigation to server route ([#145](https://github.com/sveltejs/sapper/issues/145))
+* Don't serve error page for server route errors ([#138](https://github.com/sveltejs/sapper/issues/138))
+
+## 0.7.5
+
+* Allow dynamic parameters inside route parts ([#139](https://github.com/sveltejs/sapper/issues/139))
+
+## 0.7.4
+
+* Force `NODE_ENV='production'` when running `build` or `export` ([#141](https://github.com/sveltejs/sapper/issues/141))
+* Use source-map-support ([#134](https://github.com/sveltejs/sapper/pull/134))
+
+## 0.7.3
+
+* Handle webpack assets that are arrays instead of strings ([#131](https://github.com/sveltejs/sapper/pull/131))
+* Wait for new server to start before broadcasting HMR update ([#129](https://github.com/sveltejs/sapper/pull/129))
+
+## 0.7.2
+
+* Add `hmr-client.js` to package
+* Wait until first successful client build before creating service-worker.js
+
+## 0.7.1
+
+* Add missing `tslib` dependency
+
+## 0.7.0
+
+* Restructure app layout (see [migration guide](https://sapper.svelte.technology/guide#0-6-to-0-7)) ([#126](https://github.com/sveltejs/sapper/pull/126))
+* Support `this.redirect(status, location)` and `this.error(status, error)` in `preload` functions ([#127](https://github.com/sveltejs/sapper/pull/127))
+* Add `sapper dev` command
+* Add `sapper --help` command
+
+## 0.6.4
+
+* Prevent phantom HMR requests in production mode ([#114](https://github.com/sveltejs/sapper/pull/114))
+
+## 0.6.3
+
+* Ignore non-HTML responses when crawling during `export`
+* Build in prod mode for `export`
+
+## 0.6.2
+
+* Handle unspecified type in `sapper export`
+
+## 0.6.1
+
+* Fix `pkg.files` and `pkg.bin`
+
+## 0.6.0
+
+* Hydrate on first load, and only on first load ([#93](https://github.com/sveltejs/sapper/pull/93))
+* Identify clashes between page and server routes ([#96](https://github.com/sveltejs/sapper/pull/96))
+* Remove Express-specific utilities, for compatbility with Polka et al ([#94](https://github.com/sveltejs/sapper/issues/94))
+* Return a promise from `init` when first page has rendered ([#99](https://github.com/sveltejs/sapper/issues/99))
+* Handle invalid hash links ([#104](https://github.com/sveltejs/sapper/pull/104))
+* Avoid `URLSearchParams` ([#107](https://github.com/sveltejs/sapper/pull/107))
+* Don't automatically set `Content-Type` for server routes ([#111](https://github.com/sveltejs/sapper/pull/111))
+* Handle empty query string routes, e.g. `/?` ([#105](https://github.com/sveltejs/sapper/pull/105))
+
+## 0.5.1
+
+* Only write service-worker.js to filesystem in dev mode ([#90](https://github.com/sveltejs/sapper/issues/90))
+
+## 0.5.0
+
+* Experimental support for `sapper export` ([#9](https://github.com/sveltejs/sapper/issues/9))
+* Lazily load chokidar, for faster startup ([#64](https://github.com/sveltejs/sapper/pull/64))
+
+## 0.4.0
+
+* `%sapper.main%` has been replaced with `%sapper.scripts%` ([#86](https://github.com/sveltejs/sapper/issues/86))
+* Node 6 support ([#67](https://github.com/sveltejs/sapper/pull/67))
+* Explicitly load css-loader and style-loader ([#72](https://github.com/sveltejs/sapper/pull/72))
+* DELETE requests are handled with `del` exports ([#77](https://github.com/sveltejs/sapper/issues/77))
+* Send preloaded data for first route to client, where possible ([#3](https://github.com/sveltejs/sapper/issues/3))
+
+## 0.3.2
+
+* Expose `prefetch` function ([#61](https://github.com/sveltejs/sapper/pull/61))
+
+## 0.3.1
+
+* Fix missing `runtime.js`
+
+## 0.3.0
+
+* Move `sapper/runtime/app.js` to `sapper/runtime.js`
+* Cancel navigation if overtaken by second navigation ([#48](https://github.com/sveltejs/sapper/issues/48))
+* Store preloaded data, to avoiding double prefetching ([#49](https://github.com/sveltejs/sapper/issues/49))
+* Pass server request object to `preload` ([#54](https://github.com/sveltejs/sapper/pull/54))
+* Nested routes ([#55](https://github.com/sveltejs/sapper/issues/55))
+
+## 0.2.10
+
+* Handle deep links correctly ([#44](https://github.com/sveltejs/sapper/issues/44))
+
+## 0.2.9
+
+* Don't write files to disk in prod mode
+
+## 0.2.8
+
+* Add `goto` function ([#29](https://github.com/sveltejs/sapper/issues/29))
+* Don't use `/tmp` as destination in Now environments
+
+## 0.2.7
+
+* Fix streaming bug
+
+## 0.2.6
+
+* Render main.js back to templates, to allow relative imports ([#40](https://github.com/sveltejs/sapper/issues/40))
+
+## 0.2.5
+
+* Fix nested routes on Windows ([#39](https://github.com/sveltejs/sapper/pull/39))
+* Rebundle when routes and main.js change ([#34](https://github.com/sveltejs/sapper/pull/34))
+* Add `Link...preload` headers for JavaScript assets ([#2](https://github.com/sveltejs/sapper/issues/2))
+* Stream document up to first dynamic content ([#19](https://github.com/sveltejs/sapper/issues/19))
+* Error if routes clash ([#33](https://github.com/sveltejs/sapper/issues/33))
+
+## 0.2.4
+
+* Posixify path to HMR client
+
+## 0.2.3
+
+* Posixify import paths, even on Windows ([#31](https://github.com/sveltejs/sapper/pull/31))
+* Pass `url` to 404 handler
+
+## 0.2.2
+
+* Create destination directory when building, don't assume it's already there from dev mode
+* We have tests now!
+
+## 0.2.1
+
+* Inject HMR logic in dev mode
+
+## 0.2.0
+
+* Separate `sapper build` from prod server ([#21](https://github.com/sveltejs/sapper/issues/21))
+
+## 0.1.3-5
+
+* Fix typo
+
+## 0.1.2
+
+* Use `atime.getTime()` and `mtime.getTime()` instead of `atimeMs` and `mtimeMs` ([#11](https://github.com/sveltejs/sapper/issues/11))
+* Make dest dir before anyone tries to write to it ([#18](https://github.com/sveltejs/sapper/pull/18))
+
+## 0.1.1
+
+* Expose resolved pathname to `sapper/runtime/app.js` as `__app__` inside main.js
+
+## 0.1.0
+
+* First public preview
--- a/9
+++ b/9
@@ -0,0 +1,9 @@
+Copyright (c) 2017 [these people](https://github.com/sveltejs/sapper/graphs/contributors).
+
+Permission is hereby granted by the authors of this software, to any person, to use the software for any purpose, free of charge, including the rights to run, read, copy, change, distribute and sell it, and including usage rights to any patents the authors may hold on it, subject to the following conditions:
+
+This license, or a link to its text, must be included with all copies of the software and any derivative works.
+
+Any modification to the software submitted to the authors may be incorporated into the software under the terms of this license.
+
+The software is provided "as is", without warranty of any kind, including but not limited to the warranties of title, fitness, merchantability and non-infringement. The authors have no obligation to provide support or updates for the software, and may not be held liable for any damages, claims or other liability arising from its use.
--- a/README.md
+++ b/README.md
@@ -1,90 +1,75 @@
 # sapper

-Combat-ready apps, engineered by Svelte.
-
-## This is not a thing yet
-
-If you visit this README in a few weeks, hopefully it will have blossomed into the app development framework we deserve. Right now, it's just a set of ideas.
-
---
-
-[Next.js](https://github.com/zeit/next.js/) introduced a beautiful idea — that you should be able to build your app as universal React components in a special `pages` directory, and the framework should take care of routing and rendering on both client and server. What if we did the same thing for Svelte?
-
-High-level goals:
-
-* Extreme ease of development
-* Code-splitting and HMR out of the box (probably via webpack)
-* Best-in-class performance
-* As little magic as possible. Anyone should be able to understand how everything fits together, and e.g. make changes to the webpack config
+[Military-grade progressive web apps, powered by Svelte.](https://sapper.svelte.technology)


-## Design
+## What is Sapper?

-A Sapper app is just an Express app (conventionally, `server.js`) that uses the `sapper` middleware:
+Sapper is a framework for building high-performance universal web apps. [Read the guide](https://sapper.svelte.technology/guide) or the [introductory blog post](https://svelte.technology/blog/sapper-towards-the-ideal-web-app-framework) to learn more.

-```js
-const app = require('express')();
-const sapper = require('sapper');

-const app = express();
+## Get started

-app.use(sapper());
+Clone the [starter project template](https://github.com/sveltejs/sapper-template) with [degit](https://github.com/rich-harris/degit)...

-const { PORT = 3000 } = process.env;
-app.listen(PORT, () => {
-  console.log(`listening on port ${PORT}`);
-});
+```bash
+npx degit sveltejs/sapper-template my-app
 ```

-The middleware serves pages that match files in the `routes` directory, and assets generated by webpack. In development mode, the middleware once activated watches `routes` to keep the app up-to-date.
+...then install dependencies and start the dev server...

-
-## Routing
-
-Like Next, routes are defined by the project directory structure, but with some crucial differences:
-
-* Files with an `.html` extension are treated as Svelte components. The `routes/about.html` (or `routes/about/index.html`) would create the `/about` route.
-* Files with a `.js` or `.mjs` extension are more generic route handlers. These files should export functions corresponding to the HTTP methods they support (example below).
-* Instead of route masking, we embed parameters in the filename. For example `post/%id%.html` maps to `/post/:id`, and the component will be rendered with the appropriate parameter.
-* Nested routes (read [this article](https://joshduff.com/2015-06-why-you-need-a-state-router.md)) can be handled by creating a file that matches the subroute — for example, `routes/app/settings/%submenu%.html` would match `/app/settings/profile` *and* `app/settings`, but in the latter case the `submenu` parameter would be `null`.
-
-An example of a generic route:
-
-```js
-// routes/api/post/%id%.js
-export async function get(req, res) {
-  try {
-    const data = await getPostFromDatabase(req.params.id);
-    const json = JSON.stringify(data);
-
-    res.set({
-      'Content-Type': 'application/json',
-      'Content-Length': json.length
-    });
-
-    res.send(json);
-  } catch (err) {
-    res.status(500).send(err.message);
-  }
-}
+```bash
+cd my-app
+npm install
+npm run dev
 ```

-Or, if you omit the `res` argument, it can use the return value:
+...and navigate to [localhost:3000](http://localhost:3000). To build and run in production mode:

-```js
-// routes/api/post/%id%.js
-export async function get(req, res) {
-  return await getPostFromDatabase(req.params.id);
-}
+```bash
+npm run build
+npm start
 ```

+## Development

-## Things to figure out
+Pull requests are encouraged and always welcome. [Pick an issue](https://github.com/sveltejs/sapper/issues?q=is%3Aissue+is%3Aopen+sort%3Aupdated-desc) and help us out!

-* How to customise the overall page template
-* An equivalent of `getInitialProps`
-* Critical CSS
-* `store` integration
-* Route transitions
-* Equivalent of `next export`
-* ...and lots of other things that haven't occurred to me yet.
+To install and work on Sapper locally:
+
+```bash
+git clone git@github.com:sveltejs/sapper.git
+cd sapper
+npm install
+npm run dev
+```
+
+### Linking to a Live Project
+
+You can make changes locally to Sapper and test it against a local Sapper project. For a quick project that takes almost no setup, use the default [sapper-template](https://github.com/sveltejs/sapper-template) project. Instruction on setup are found in that project repository.
+
+To link Sapper to your project, from the root of your local Sapper git checkout:
+
+```bash
+cd sapper
+npm link
+```
+
+Then, to link from `sapper-template` (or any other given project):
+
+```bash
+cd sapper-template
+npm link sapper
+```
+
+You should be good to test changes locally.
+
+### Running Tests
+
+```bash
+npm run test
+```
+
+## License
+
+[LIL](LICENSE)
--- a/api.js
+++ b/api.js
@@ -0,0 +1 @@
+module.exports = require('./dist/api.js');
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -0,0 +1,21 @@
+version: "{build}"
+
+shallow_clone: true
+
+init:
+  - git config --global core.autocrlf false
+
+build: off
+
+environment:
+  matrix:
+    # node.js
+    - nodejs_version: 10.5
+
+install:
+  - ps: Install-Product node $env:nodejs_version
+  - npm ci
+
+test_script:
+  - node --version && npm --version
+  - npm test
--- a/config/rollup.js
+++ b/config/rollup.js
@@ -0,0 +1 @@
+module.exports = require('../dist/rollup.js');
--- a/config/webpack.js
+++ b/config/webpack.js
@@ -0,0 +1 @@
+module.exports = require('../dist/webpack.js');
--- a/connect.js
+++ b/connect.js
@@ -1,67 +0,0 @@
-require('svelte/ssr/register');
-const esm = require('@std/esm');
-const path = require('path');
-const glob = require('glob');
-const create_matchers = require('./utils/create_matchers.js');
-
-require = esm(module, {
-	esm: 'all'
-});
-
-module.exports = function connect(opts = {}) {
-	const routes = path.resolve('routes');
-	const out = path.resolve('.sapper');
-
-	let pages = glob.sync('**/*.html', { cwd: routes });
-	let page_matchers = create_matchers(pages);
-
-	let server_routes = glob.sync('**/*.+(js|mjs)', { cwd: routes });
-	let server_route_matchers = create_matchers(server_routes);
-
-	return async function(req, res, next) {
-		const url = req.url.replace(/\?.+/, '');
-
-		for (let i = 0; i < page_matchers.length; i += 1) {
-			const matcher = page_matchers[i];
-			if (matcher.test(url)) {
-				const params = matcher.exec(url);
-				const Component = require(`${routes}/${matcher.file}`);
-
-				res.end(Component.render({
-					params,
-					query: req.query
-				}));
-				return;
-			}
-		}
-
-		for (let i = 0; i < server_route_matchers.length; i += 1) {
-			const matcher = server_route_matchers[i];
-			if (matcher.test(url)) {
-				req.params = matcher.exec(url);
-				const route = require(`${routes}/${matcher.file}`);
-
-				const handler = route[req.method.toLowerCase()];
-				if (handler) {
-					if (handler.length === 2) {
-						handler(req, res);
-					} else {
-						const data = await handler(req);
-
-						// TODO headers, error handling
-						if (typeof data === 'string') {
-							res.end(data);
-						} else {
-							res.end(JSON.stringify(data));
-						}
-					}
-
-					return;
-				}
-			}
-		}
-
-		next();
-	};
-};
-
--- a/index.js
+++ b/index.js
@@ -0,0 +1 @@
+throw new Error(`As of Sapper 0.22, you should not import 'sapper' directly. See https://sapper.svelte.technology/guide#0-21-to-0-22 for more information`);
--- a/mocha.opts
+++ b/mocha.opts
@@ -1,2 +1,5 @@
+--require source-map-support/register
+--require ts-node/register
 --recursive
-utils/**/*.test.js
+test/unit/*/*.ts
+test/apps/*/test.ts
--- a/package-lock.json
+++ b/package-lock.json
--- a/package.json
+++ b/package.json
@@ -1,20 +1,78 @@
 {
  "name": "sapper",
-  "version": "0.0.1",
-  "description": "Combat-ready apps, engineered by Svelte",
-  "main": "connect.js",
+  "version": "0.24.3",
+  "description": "Military-grade apps, engineered by Svelte",
+  "bin": {
+    "sapper": "./sapper"
+  },
+  "files": [
+    "*.js",
+    "webpack",
+    "config",
+    "sapper",
+    "dist/*.js",
+    "templates/*.js"
+  ],
  "directories": {
    "test": "test"
  },
  "dependencies": {
-    "@std/esm": "^0.18.0"
+    "html-minifier": "^3.5.20",
+    "shimport": "0.0.11",
+    "source-map-support": "^0.5.9",
+    "sourcemap-codec": "^1.4.3",
+    "string-hash": "^1.1.3",
+    "tslib": "^1.9.3"
  },
  "devDependencies": {
-    "mocha": "^4.0.1",
-	"svelte": "^1.47.0"
+    "@types/mkdirp": "^0.5.2",
+    "@types/mocha": "^5.2.5",
+    "@types/node": "^10.12.0",
+    "@types/puppeteer": "^1.9.0",
+    "@types/rimraf": "^2.0.2",
+    "agadoo": "^1.0.1",
+    "cheap-watch": "^1.0.0",
+    "cookie": "^0.3.1",
+    "devalue": "^1.0.4",
+    "eslint": "^5.7.0",
+    "eslint-plugin-import": "^2.14.0",
+    "kleur": "^2.0.2",
+    "mkdirp": "^0.5.1",
+    "mocha": "^5.2.0",
+    "node-fetch": "^2.2.0",
+    "npm-run-all": "^4.1.5",
+    "polka": "^0.5.1",
+    "port-authority": "^1.0.5",
+    "pretty-bytes": "^5.1.0",
+    "puppeteer": "^1.9.0",
+    "require-relative": "^0.8.7",
+    "rimraf": "^2.6.2",
+    "rollup": "^0.66.6",
+    "rollup-plugin-commonjs": "^9.2.0",
+    "rollup-plugin-json": "^3.1.0",
+    "rollup-plugin-node-resolve": "^3.4.0",
+    "rollup-plugin-replace": "^2.1.0",
+    "rollup-plugin-string": "^2.0.2",
+    "rollup-plugin-svelte": "^4.3.2",
+    "rollup-plugin-typescript": "^1.0.0",
+    "sade": "^1.4.1",
+    "sander": "^0.6.0",
+    "sirv": "^0.2.2",
+    "svelte": "^2.13.5",
+    "svelte-loader": "^2.11.0",
+    "ts-node": "^7.0.1",
+    "typescript": "^3.1.3",
+    "webpack": "^4.20.2",
+    "webpack-format-messages": "^2.0.3"
  },
  "scripts": {
-    "test": "mocha --opts mocha.opts"
+    "test": "mocha --opts mocha.opts",
+    "pretest": "npm run build",
+    "build": "rm -rf dist && rollup -c",
+    "prepare": "npm run build",
+    "dev": "rollup -cw",
+    "prepublishOnly": "npm test",
+    "update_mime_types": "curl http://svn.apache.org/repos/asf/httpd/httpd/trunk/docs/conf/mime.types | grep -e \"^[^#]\" > templates/src/server/middleware/mime-types.md"
  },
  "repository": "https://github.com/sveltejs/sapper",
  "keywords": [
@@ -29,8 +87,5 @@
  "bugs": {
    "url": "https://github.com/sveltejs/sapper/issues"
  },
-  "homepage": "https://github.com/sveltejs/sapper#readme",
-  "@std/esm": {
-    "esm": "js"
-  }
+  "homepage": "https://github.com/sveltejs/sapper#readme"
 }
--- a/rollup.config.js
+++ b/rollup.config.js
@@ -0,0 +1,65 @@
+import typescript from 'rollup-plugin-typescript';
+import string from 'rollup-plugin-string';
+import json from 'rollup-plugin-json';
+import resolve from 'rollup-plugin-node-resolve';
+import commonjs from 'rollup-plugin-commonjs';
+import pkg from './package.json';
+import { builtinModules } from 'module';
+
+const external = [].concat(
+	Object.keys(pkg.dependencies),
+	Object.keys(process.binding('natives')),
+	'sapper/core.js'
+);
+
+function template(kind, external, target) {
+	return {
+		input: `templates/src/${kind}/index.ts`,
+		output: {
+			file: `templates/${kind}.js`,
+			format: 'es'
+		},
+		external,
+		plugins: [
+			resolve(),
+			commonjs(),
+			string({
+				include: '**/*.md'
+			}),
+			typescript({
+				typescript: require('typescript'),
+				target
+			})
+		]
+	};
+}
+
+export default [
+	template('client', ['__ROOT__', '__ERROR__'], 'ES2017'),
+	template('server', builtinModules, 'ES2015'),
+
+	{
+		input: [
+			`src/api.ts`,
+			`src/cli.ts`,
+			`src/core.ts`,
+			`src/config/rollup.ts`,
+			`src/config/webpack.ts`
+		],
+		output: {
+			dir: 'dist',
+			format: 'cjs',
+			sourcemap: true
+		},
+		external,
+		plugins: [
+			json(),
+			resolve(),
+			commonjs(),
+			typescript({
+				typescript: require('typescript')
+			})
+		],
+		experimentalCodeSplitting: true
+	}
+];
--- a/2
+++ b/2
@@ -0,0 +1,2 @@
+#!/usr/bin/env node
+require('./dist/cli.js');
--- a/sapper-dev-client.js
+++ b/sapper-dev-client.js
@@ -0,0 +1,40 @@
+let source;
+
+function check() {
+	if (typeof module === 'undefined') return;
+
+	if (module.hot.status() === 'idle') {
+		module.hot.check(true).then(modules => {
+			console.log(`[SAPPER] applied HMR update`);
+		});
+	}
+}
+
+export function connect(port) {
+	if (source || !window.EventSource) return;
+
+	source = new EventSource(`http://${window.location.hostname}:${port}/__sapper__`);
+
+	window.source = source;
+
+	source.onopen = function(event) {
+		console.log(`[SAPPER] dev client connected`);
+	};
+
+	source.onerror = function(error) {
+		console.error(error);
+	};
+
+	source.onmessage = function(event) {
+		const data = JSON.parse(event.data);
+		if (!data) return; // just a heartbeat
+
+		if (data.action === 'reload') {
+			window.location.reload();
+		}
+
+		if (data.status === 'completed') {
+			check();
+		}
+	};
+}
--- a/src/api.ts
+++ b/src/api.ts
@@ -0,0 +1,4 @@
+export { dev } from './api/dev';
+export { build } from './api/build';
+export { export } from './api/export';
+export { find_page } from './api/find_page';
--- a/src/api/build.ts
+++ b/src/api/build.ts
@@ -0,0 +1,138 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import mkdirp from 'mkdirp';
+import rimraf from 'rimraf';
+import minify_html from './utils/minify_html';
+import { create_compilers, create_main_manifests, create_manifest_data, create_serviceworker_manifest } from '../core';
+import { copy_shimport } from './utils/copy_shimport';
+import read_template from '../core/read_template';
+import { CompileResult } from '../core/create_compilers/interfaces';
+import { noop } from './utils/noop';
+import validate_bundler from './utils/validate_bundler';
+
+type Opts = {
+	cwd?: string;
+	src?: string;
+	routes?: string;
+	dest?: string;
+	output?: string;
+	static?: string;
+	legacy?: boolean;
+	bundler?: 'rollup' | 'webpack';
+	oncompile?: ({ type, result }: { type: string, result: CompileResult }) => void;
+};
+
+export async function build({
+	cwd,
+	src = 'src',
+	routes = 'src/routes',
+	output = '__sapper__',
+	static: static_files = 'static',
+	dest = '__sapper__/build',
+
+	bundler,
+	legacy = false,
+	oncompile = noop
+}: Opts = {}) {
+	bundler = validate_bundler(bundler);
+
+	cwd = path.resolve(cwd);
+	src = path.resolve(cwd, src);
+	dest = path.resolve(cwd, dest);
+	routes = path.resolve(cwd, routes);
+	output = path.resolve(cwd, output);
+	static_files = path.resolve(cwd, static_files);
+	dest = path.resolve(cwd, dest);
+
+	if (legacy && bundler === 'webpack') {
+		throw new Error(`Legacy builds are not supported for projects using webpack`);
+	}
+
+	rimraf.sync(path.join(dest, '**/*'));
+	mkdirp.sync(`${dest}/client`);
+	copy_shimport(dest);
+
+	// minify src/template.html
+	// TODO compile this to a function? could be quicker than str.replace(...).replace(...).replace(...)
+	const template = read_template(src);
+
+	// remove this in a future version
+	if (template.indexOf('%sapper.base%') === -1) {
+		const error = new Error(`As of Sapper v0.10, your template.html file must include %sapper.base% in the <head>`);
+		error.code = `missing-sapper-base`;
+		throw error;
+	}
+
+	fs.writeFileSync(`${dest}/template.html`, minify_html(template));
+
+	const manifest_data = create_manifest_data(routes);
+
+	// create src/manifest/client.js and src/manifest/server.js
+	create_main_manifests({
+		bundler,
+		manifest_data,
+		cwd,
+		src,
+		dest,
+		routes,
+		output,
+		dev: false
+	});
+
+	const { client, server, serviceworker } = await create_compilers(bundler, cwd, src, dest, true);
+
+	const client_result = await client.compile();
+	oncompile({
+		type: 'client',
+		result: client_result
+	});
+
+	const build_info = client_result.to_json(manifest_data, { src, routes, dest });
+
+	if (legacy) {
+		process.env.SAPPER_LEGACY_BUILD = 'true';
+		const { client } = await create_compilers(bundler, cwd, src, dest, true);
+
+		const client_result = await client.compile();
+
+		oncompile({
+			type: 'client (legacy)',
+			result: client_result
+		});
+
+		client_result.to_json(manifest_data, { src, routes, dest });
+		build_info.legacy_assets = client_result.assets;
+		delete process.env.SAPPER_LEGACY_BUILD;
+	}
+
+	fs.writeFileSync(path.join(dest, 'build.json'), JSON.stringify(build_info));
+
+	const server_stats = await server.compile();
+	oncompile({
+		type: 'server',
+		result: server_stats
+	});
+
+	let serviceworker_stats;
+
+	if (serviceworker) {
+
+		const client_files = client_result.chunks
+			.filter(chunk => !chunk.file.endsWith('.map')) // SW does not need to cache sourcemap files
+			.map(chunk => `client/${chunk.file}`);
+
+		create_serviceworker_manifest({
+			manifest_data,
+			output,
+			client_files,
+			static_files
+		});
+
+		serviceworker_stats = await serviceworker.compile();
+
+		oncompile({
+			type: 'serviceworker',
+			result: serviceworker_stats
+		});
+	}
+}
--- a/src/api/dev.ts
+++ b/src/api/dev.ts
@@ -0,0 +1,507 @@
+import * as path from 'path';
+import * as fs from 'fs';
+import * as http from 'http';
+import * as child_process from 'child_process';
+import * as ports from 'port-authority';
+import mkdirp from 'mkdirp';
+import rimraf from 'rimraf';
+import { EventEmitter } from 'events';
+import { create_manifest_data, create_main_manifests, create_compilers, create_serviceworker_manifest } from '../core';
+import { Compiler, Compilers } from '../core/create_compilers';
+import { CompileResult } from '../core/create_compilers/interfaces';
+import Deferred from './utils/Deferred';
+import validate_bundler from './utils/validate_bundler';
+import { copy_shimport } from './utils/copy_shimport';
+import { ManifestData, FatalEvent, ErrorEvent, ReadyEvent, InvalidEvent } from '../interfaces';
+import read_template from '../core/read_template';
+import { noop } from './utils/noop';
+
+type Opts = {
+	cwd?: string,
+	src?: string,
+	dest?: string,
+	routes?: string,
+	output?: string,
+	static?: string,
+	'dev-port'?: number,
+	live?: boolean,
+	hot?: boolean,
+	'devtools-port'?: number,
+	bundler?: 'rollup' | 'webpack',
+	port?: number
+};
+
+export function dev(opts: Opts) {
+	return new Watcher(opts);
+}
+
+class Watcher extends EventEmitter {
+	bundler: 'rollup' | 'webpack';
+	dirs: {
+		cwd: string;
+		src: string;
+		dest: string;
+		routes: string;
+		output: string;
+		static: string;
+	}
+	port: number;
+	closed: boolean;
+
+	dev_port: number;
+	live: boolean;
+	hot: boolean;
+
+	devtools_port: number;
+
+	dev_server: DevServer;
+	proc: child_process.ChildProcess;
+	filewatchers: Array<{ close: () => void }>;
+	deferred: Deferred;
+
+	crashed: boolean;
+	restarting: boolean;
+	current_build: {
+		changed: Set<string>;
+		rebuilding: Set<string>;
+		unique_warnings: Set<string>;
+		unique_errors: Set<string>;
+	}
+
+	constructor({
+		cwd = '.',
+		src = 'src',
+		routes = 'src/routes',
+		output = '__sapper__',
+		static: static_files = 'static',
+		dest = '__sapper__/dev',
+		'dev-port': dev_port,
+		live,
+		hot,
+		'devtools-port': devtools_port,
+		bundler,
+		port = +process.env.PORT
+	}: Opts) {
+		super();
+
+		cwd = path.resolve(cwd);
+
+		this.bundler = validate_bundler(bundler);
+		this.dirs = {
+			cwd,
+			src: path.resolve(cwd, src),
+			dest: path.resolve(cwd, dest),
+			routes: path.resolve(cwd, routes),
+			output: path.resolve(cwd, output),
+			static: path.resolve(cwd, static_files)
+		};
+
+		this.port = port;
+		this.closed = false;
+
+		this.dev_port = dev_port;
+		this.live = live;
+		this.hot = hot;
+
+		this.devtools_port = devtools_port;
+
+		this.filewatchers = [];
+
+		this.current_build = {
+			changed: new Set(),
+			rebuilding: new Set(),
+			unique_errors: new Set(),
+			unique_warnings: new Set()
+		};
+
+		// remove this in a future version
+		const template = read_template(src);
+		if (template.indexOf('%sapper.base%') === -1) {
+			const error = new Error(`As of Sapper v0.10, your template.html file must include %sapper.base% in the <head>`);
+			error.code = `missing-sapper-base`;
+			throw error;
+		}
+
+		process.env.NODE_ENV = 'development';
+
+		process.on('exit', () => {
+			this.close();
+		});
+
+		this.init();
+	}
+
+	async init() {
+		if (this.port) {
+			if (!await ports.check(this.port)) {
+				this.emit('fatal', <FatalEvent>{
+					message: `Port ${this.port} is unavailable`
+				});
+				return;
+			}
+		} else {
+			this.port = await ports.find(3000);
+		}
+
+		const { cwd, src, dest, routes, output, static: static_files } = this.dirs;
+		rimraf.sync(dest);
+		mkdirp.sync(`${dest}/client`);
+		if (this.bundler === 'rollup') copy_shimport(dest);
+
+		if (!this.dev_port) this.dev_port = await ports.find(10000);
+
+		// Chrome looks for debugging targets on ports 9222 and 9229 by default
+		if (!this.devtools_port) this.devtools_port = await ports.find(9222);
+
+		let manifest_data: ManifestData;
+
+		try {
+			manifest_data = create_manifest_data(routes);
+			create_main_manifests({
+				bundler: this.bundler,
+				manifest_data,
+				dev: true,
+				dev_port: this.dev_port,
+				cwd, src, dest, routes, output
+			});
+		} catch (err) {
+			this.emit('fatal', <FatalEvent>{
+				message: err.message
+			});
+			return;
+		}
+
+		this.dev_server = new DevServer(this.dev_port);
+
+		this.filewatchers.push(
+			watch_dir(
+				routes,
+				({ path: file, stats }) => {
+					if (stats.isDirectory()) {
+						return path.basename(file)[0] !== '_';
+					}
+					return true;
+				},
+				() => {
+					try {
+						const new_manifest_data = create_manifest_data(routes);
+						create_main_manifests({
+							bundler: this.bundler,
+							manifest_data, // TODO is this right? not new_manifest_data?
+							dev: true,
+							dev_port: this.dev_port,
+							cwd, src, dest, routes, output
+						});
+
+						manifest_data = new_manifest_data;
+					} catch (err) {
+						this.emit('error', <ErrorEvent>{
+							message: err.message
+						});
+					}
+				}
+			),
+
+			fs.watch(`${src}/template.html`, () => {
+				this.dev_server.send({
+					action: 'reload'
+				});
+			})
+		);
+
+		let deferred = new Deferred();
+
+		// TODO watch the configs themselves?
+		const compilers: Compilers = await create_compilers(this.bundler, cwd, src, dest, false);
+
+		const emitFatal = () => {
+			this.emit('fatal', <FatalEvent>{
+				message: `Server crashed`
+			});
+
+			this.crashed = true;
+			this.proc = null;
+		};
+
+		this.watch(compilers.server, {
+			name: 'server',
+
+			invalid: filename => {
+				this.restart(filename, 'server');
+			},
+
+			handle_result: (result: CompileResult) => {
+				deferred.promise.then(() => {
+					const restart = () => {
+						this.crashed = false;
+
+						ports.wait(this.port)
+							.then((() => {
+								this.emit('ready', <ReadyEvent>{
+									port: this.port,
+									process: this.proc
+								});
+
+								if (this.hot && this.bundler === 'webpack') {
+									this.dev_server.send({
+										status: 'completed'
+									});
+								} else {
+									this.dev_server.send({
+										action: 'reload'
+									});
+								}
+							}))
+							.catch(err => {
+								if (this.crashed) return;
+
+								this.emit('fatal', <FatalEvent>{
+									message: `Server is not listening on port ${this.port}`
+								});
+							});
+					};
+
+					if (this.proc) {
+						this.proc.removeListener('exit', emitFatal);
+						this.proc.kill();
+						this.proc.on('exit', restart);
+					} else {
+						restart();
+					}
+
+					// we need to give the child process its own DevTools port,
+					// otherwise Node will try to use the parent's (and fail)
+					const debugArgRegex = /--inspect(?:-brk|-port)?|--debug-port/;
+					const execArgv = process.execArgv.slice();
+					if (execArgv.some((arg: string) => !!arg.match(debugArgRegex))) {
+						execArgv.push(`--inspect-port=${this.devtools_port}`);
+					}
+
+					this.proc = child_process.fork(`${dest}/server/server.js`, [], {
+						cwd: process.cwd(),
+						env: Object.assign({
+							PORT: this.port
+						}, process.env),
+						stdio: ['ipc'],
+						execArgv
+					});
+
+					this.proc.stdout.on('data', chunk => {
+						this.emit('stdout', chunk);
+					});
+
+					this.proc.stderr.on('data', chunk => {
+						this.emit('stderr', chunk);
+					});
+
+					this.proc.on('message', message => {
+						if (message.__sapper__ && message.event === 'basepath') {
+							this.emit('basepath', {
+								basepath: message.basepath
+							});
+						}
+					});
+
+					this.proc.on('exit', emitFatal);
+				});
+			}
+		});
+
+		this.watch(compilers.client, {
+			name: 'client',
+
+			invalid: filename => {
+				this.restart(filename, 'client');
+				deferred = new Deferred();
+
+				// TODO we should delete old assets. due to a webpack bug
+				// i don't even begin to comprehend, this is apparently
+				// quite difficult
+			},
+
+			handle_result: (result: CompileResult) => {
+				fs.writeFileSync(
+					path.join(dest, 'build.json'),
+
+					// TODO should be more explicit that to_json has effects
+					JSON.stringify(result.to_json(manifest_data, this.dirs), null, '  ')
+				);
+
+				const client_files = result.chunks.map(chunk => `client/${chunk.file}`);
+
+				create_serviceworker_manifest({
+					manifest_data,
+					output,
+					client_files,
+					static_files
+				});
+
+				deferred.fulfil();
+
+				// we need to wait a beat before watching the service
+				// worker, because of some webpack nonsense
+				setTimeout(watch_serviceworker, 100);
+			}
+		});
+
+		let watch_serviceworker = compilers.serviceworker
+			? () => {
+				watch_serviceworker = noop;
+
+				this.watch(compilers.serviceworker, {
+					name: 'service worker'
+				});
+			}
+			: noop;
+	}
+
+	close() {
+		if (this.closed) return;
+		this.closed = true;
+
+		if (this.dev_server) this.dev_server.close();
+
+		if (this.proc) this.proc.kill();
+		this.filewatchers.forEach(watcher => {
+			watcher.close();
+		});
+	}
+
+	restart(filename: string, type: string) {
+		if (this.restarting) {
+			this.current_build.changed.add(filename);
+			this.current_build.rebuilding.add(type);
+		} else {
+			this.restarting = true;
+
+			this.current_build = {
+				changed: new Set([filename]),
+				rebuilding: new Set([type]),
+				unique_warnings: new Set(),
+				unique_errors: new Set()
+			};
+
+			process.nextTick(() => {
+				this.emit('invalid', <InvalidEvent>{
+					changed: Array.from(this.current_build.changed),
+					invalid: {
+						server: this.current_build.rebuilding.has('server'),
+						client: this.current_build.rebuilding.has('client'),
+						serviceworker: this.current_build.rebuilding.has('serviceworker'),
+					}
+				});
+
+				this.restarting = false;
+			});
+		}
+	}
+
+	watch(compiler: Compiler, { name, invalid = noop, handle_result = noop }: {
+		name: string,
+		invalid?: (filename: string) => void;
+		handle_result?: (result: CompileResult) => void;
+	}) {
+		compiler.oninvalid(invalid);
+
+		compiler.watch((err?: Error, result?: CompileResult) => {
+			if (err) {
+				this.emit('error', <ErrorEvent>{
+					type: name,
+					message: err.message
+				});
+			} else {
+				this.emit('build', {
+					type: name,
+
+					duration: result.duration,
+					errors: result.errors,
+					warnings: result.warnings
+				});
+
+				handle_result(result);
+			}
+		});
+	}
+}
+
+const INTERVAL = 10000;
+
+class DevServer {
+	clients: Set<http.ServerResponse>;
+	interval: NodeJS.Timer;
+	_: http.Server;
+
+	constructor(port: number, interval = 10000) {
+		this.clients = new Set();
+
+		this._ = http.createServer((req, res) => {
+			if (req.url !== '/__sapper__') return;
+
+			req.socket.setKeepAlive(true);
+			res.writeHead(200, {
+				'Access-Control-Allow-Origin': '*',
+				'Access-Control-Allow-Headers': 'Cache-Control',
+				'Content-Type': 'text/event-stream;charset=utf-8',
+				'Cache-Control': 'no-cache, no-transform',
+				'Connection': 'keep-alive',
+				// While behind nginx, event stream should not be buffered:
+				// http://nginx.org/docs/http/ngx_http_proxy_module.html#proxy_buffering
+				'X-Accel-Buffering': 'no'
+			});
+
+			res.write('\n');
+
+			this.clients.add(res);
+			req.on('close', () => {
+				this.clients.delete(res);
+			});
+		});
+
+		this._.listen(port);
+
+		this.interval = setInterval(() => {
+			this.send(null);
+		}, INTERVAL);
+	}
+
+	close() {
+		this._.close();
+		clearInterval(this.interval);
+	}
+
+	send(data: any) {
+		this.clients.forEach(client => {
+			client.write(`data: ${JSON.stringify(data)}\n\n`);
+		});
+	}
+}
+
+function watch_dir(
+	dir: string,
+	filter: ({ path, stats }: { path: string, stats: fs.Stats }) => boolean,
+	callback: () => void
+) {
+	let watch: any;
+	let closed = false;
+
+	import('cheap-watch').then(CheapWatch => {
+		if (closed) return;
+
+		watch = new CheapWatch({ dir, filter, debounce: 50 });
+
+		watch.on('+', ({ isNew }: { isNew: boolean }) => {
+			if (isNew) callback();
+		});
+
+		watch.on('-', callback);
+
+		watch.init();
+	});
+
+	return {
+		close: () => {
+			if (watch) watch.close();
+			closed = true;
+		}
+	};
+}
--- a/src/api/export.ts
+++ b/src/api/export.ts
@@ -0,0 +1,200 @@
+import * as child_process from 'child_process';
+import * as path from 'path';
+import * as sander from 'sander';
+import * as url from 'url';
+import fetch from 'node-fetch';
+import * as ports from 'port-authority';
+import clean_html from './utils/clean_html';
+import minify_html from './utils/minify_html';
+import Deferred from './utils/Deferred';
+import { noop } from './utils/noop';
+
+type Opts = {
+	build_dir?: string,
+	export_dir?: string,
+	cwd?: string,
+	static?: string,
+	basepath?: string,
+	timeout?: number | false,
+	oninfo?: ({ message }: { message: string }) => void;
+	onfile?: ({ file, size, status }: { file: string, size: number, status: number }) => void;
+};
+
+function resolve(from: string, to: string) {
+	return url.parse(url.resolve(from, to));
+}
+
+type URL = url.UrlWithStringQuery;
+
+export { _export as export };
+
+async function _export({
+	cwd,
+	static: static_files = 'static',
+	build_dir = '__sapper__/build',
+	export_dir = '__sapper__/export',
+	basepath = '',
+	timeout = 5000,
+	oninfo = noop,
+	onfile = noop
+}: Opts = {}) {
+	basepath = basepath.replace(/^\//, '')
+
+	cwd = path.resolve(cwd);
+	static_files = path.resolve(cwd, static_files);
+	build_dir = path.resolve(cwd, build_dir);
+	export_dir = path.resolve(cwd, export_dir, basepath);
+
+	// Prep output directory
+	sander.rimrafSync(export_dir);
+
+	sander.copydirSync(static_files).to(export_dir);
+	sander.copydirSync(build_dir, 'client').to(export_dir, 'client');
+
+	if (sander.existsSync(build_dir, 'service-worker.js')) {
+		sander.copyFileSync(build_dir, 'service-worker.js').to(export_dir, 'service-worker.js');
+	}
+
+	if (sander.existsSync(build_dir, 'service-worker.js.map')) {
+		sander.copyFileSync(build_dir, 'service-worker.js.map').to(export_dir, 'service-worker.js.map');
+	}
+
+	const port = await ports.find(3000);
+
+	const protocol = 'http:';
+	const host = `localhost:${port}`;
+	const origin = `${protocol}//${host}`;
+
+	const root = resolve(origin, basepath);
+	if (!root.href.endsWith('/')) root.href += '/';
+
+	oninfo({
+		message: `Crawling ${root.href}`
+	});
+
+	const proc = child_process.fork(path.resolve(`${build_dir}/server/server.js`), [], {
+		cwd,
+		env: Object.assign({
+			PORT: port,
+			NODE_ENV: 'production',
+			SAPPER_EXPORT: 'true'
+		}, process.env)
+	});
+
+	const seen = new Set();
+	const saved = new Set();
+
+	function save(path: string, status: number, type: string, body: string) {
+		const { pathname } = resolve(origin, path);
+		let file = decodeURIComponent(pathname.slice(1));
+
+		if (saved.has(file)) return;
+		saved.add(file);
+
+		const is_html = type === 'text/html';
+
+		if (is_html) {
+			if (pathname !== '/service-worker-index.html') {
+				file = file === '' ? 'index.html' : `${file}/index.html`;
+			}
+			body = minify_html(body);
+		}
+
+		onfile({
+			file,
+			size: body.length,
+			status
+		});
+
+		sander.writeFileSync(export_dir, file, body);
+	}
+
+	proc.on('message', message => {
+		if (!message.__sapper__ || message.event !== 'file') return;
+		save(message.url, message.status, message.type, message.body);
+	});
+
+	async function handle(url: URL) {
+		let pathname = url.pathname;
+		if (pathname !== '/service-worker-index.html') {
+		  pathname = pathname.replace(root.pathname, '') || '/'
+		}
+
+		if (seen.has(pathname)) return;
+		seen.add(pathname);
+
+		const timeout_deferred = new Deferred();
+		const the_timeout = setTimeout(() => {
+			timeout_deferred.reject(new Error(`Timed out waiting for ${url.href}`));
+		}, timeout);
+
+		const r = await Promise.race([
+			fetch(url.href, {
+				redirect: 'manual'
+			}),
+			timeout_deferred.promise
+		]);
+
+		clearTimeout(the_timeout); // prevent it hanging at the end
+
+		let type = r.headers.get('Content-Type');
+		let body = await r.text();
+
+		const range = ~~(r.status / 100);
+
+		if (range === 2) {
+			if (type === 'text/html' && pathname !== '/service-worker-index.html') {
+				const urls: URL[] = [];
+
+				const cleaned = clean_html(body);
+
+				const base_match = /<base ([\s\S]+?)>/m.exec(cleaned);
+				const base_href = base_match && get_href(base_match[1]);
+				const base = resolve(url.href, base_href);
+
+				let match;
+				let pattern = /<a ([\s\S]+?)>/gm;
+
+				while (match = pattern.exec(cleaned)) {
+					const attrs = match[1];
+					const href = get_href(attrs);
+
+					if (href) {
+						const url = resolve(base.href, href);
+
+						if (url.protocol === protocol && url.host === host) {
+							urls.push(url);
+						}
+					}
+				}
+
+				await Promise.all(urls.map(handle));
+			}
+		}
+
+		if (range === 3) {
+			const location = r.headers.get('Location');
+
+			type = 'text/html';
+			body = `<script>window.location.href = "${location.replace(origin, '')}"</script>`;
+
+			await handle(resolve(root.href, location));
+		}
+
+		save(pathname, r.status, type, body);
+	}
+
+	return ports.wait(port)
+		.then(() => handle(root))
+		.then(() => handle(resolve(root.href, 'service-worker-index.html')))
+		.then(() => proc.kill())
+		.catch(err => {
+			proc.kill();
+			throw err;
+		});
+}
+
+function get_href(attrs: string) {
+	const match = /href\s*=\s*(?:"(.*?)"|'(.+?)'|([^\s>]+))/.exec(attrs);
+	return match[1] || match[2] || match[3];
+}
--- a/src/api/find_page.ts
+++ b/src/api/find_page.ts
@@ -0,0 +1,13 @@
+import { create_manifest_data } from '../core';
+
+export function find_page(pathname: string, cwd = 'src/routes') {
+	const { pages } = create_manifest_data(cwd);
+
+	for (let i = 0; i < pages.length; i += 1) {
+		const page = pages[i];
+
+		if (page.pattern.test(pathname)) {
+			return page.parts[page.parts.length - 1].component.file;
+		}
+	}
+}
--- a/src/api/utils/Deferred.ts
+++ b/src/api/utils/Deferred.ts
@@ -0,0 +1,12 @@
+export default class Deferred {
+	promise: Promise<any>;
+	fulfil: (value?: any) => void;
+	reject: (error: Error) => void;
+
+	constructor() {
+		this.promise = new Promise((fulfil, reject) => {
+			this.fulfil = fulfil;
+			this.reject = reject;
+		});
+	}
+}
--- a/src/api/utils/clean_html.ts
+++ b/src/api/utils/clean_html.ts
@@ -0,0 +1,7 @@
+export default function clean_html(html: string) {
+	return html
+		.replace(/<!\[CDATA\[[\s\S]*?\]\]>/gm, '')
+		.replace(/(<script[\s\S]*?>)[\s\S]*?<\/script>/gm, '$1</' + 'script>')
+		.replace(/(<style[\s\S]*?>)[\s\S]*?<\/style>/gm, '$1</' + 'style>')
+		.replace(/<!--[\s\S]*?-->/gm, '');
+}
--- a/src/api/utils/copy_shimport.ts
+++ b/src/api/utils/copy_shimport.ts
@@ -0,0 +1,9 @@
+import * as fs from 'fs';
+
+export function copy_shimport(dest: string) {
+	const shimport_version = require('shimport/package.json').version;
+	fs.writeFileSync(
+		`${dest}/client/shimport@${shimport_version}.js`,
+		fs.readFileSync(require.resolve('shimport/index.js'))
+	);
+}
--- a/src/api/utils/minify_html.ts
+++ b/src/api/utils/minify_html.ts
@@ -0,0 +1,22 @@
+import { minify } from 'html-minifier';
+
+export default function minify_html(html: string) {
+	return minify(html, {
+		collapseBooleanAttributes: true,
+		collapseWhitespace: true,
+		conservativeCollapse: true,
+		decodeEntities: true,
+		html5: true,
+		ignoreCustomComments: [/^#/],
+		minifyCSS: true,
+		minifyJS: false,
+		removeAttributeQuotes: true,
+		removeComments: true,
+		removeOptionalTags: true,
+		removeRedundantAttributes: true,
+		removeScriptTypeAttributes: true,
+		removeStyleLinkTypeAttributes: true,
+		sortAttributes: true,
+		sortClassName: true
+	});
+}
--- a/src/api/utils/noop.ts
+++ b/src/api/utils/noop.ts
@@ -0,0 +1 @@
+export function noop() {}
--- a/src/api/utils/validate_bundler.ts
+++ b/src/api/utils/validate_bundler.ts
@@ -0,0 +1,38 @@
+import * as fs from 'fs';
+
+export default function validate_bundler(bundler?: 'rollup' | 'webpack') {
+	if (!bundler) {
+		bundler = (
+			fs.existsSync('rollup.config.js') ? 'rollup' :
+			fs.existsSync('webpack.config.js') ? 'webpack' :
+			null
+		);
+
+		if (!bundler) {
+			// TODO remove in a future version
+			deprecate_dir('rollup');
+			deprecate_dir('webpack');
+
+			throw new Error(`Could not find rollup.config.js or webpack.config.js`);
+		}
+	}
+
+	if (bundler !== 'rollup' && bundler !== 'webpack') {
+		throw new Error(`'${bundler}' is not a valid option for --bundler — must be either 'rollup' or 'webpack'`);
+	}
+
+	return bundler;
+}
+
+function deprecate_dir(bundler: 'rollup' | 'webpack') {
+	try {
+		const stats = fs.statSync(bundler);
+		if (!stats.isDirectory()) return;
+	} catch (err) {
+		// do nothing
+		return;
+	}
+
+	// TODO link to docs, once those docs exist
+	throw new Error(`As of Sapper 0.21, build configuration should be placed in a single ${bundler}.config.js file`);
+}
--- a/src/cli.ts
+++ b/src/cli.ts
@@ -0,0 +1,285 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import sade from 'sade';
+import colors from 'kleur';
+import * as pkg from '../package.json';
+import { elapsed, repeat, left_pad, format_milliseconds } from './utils';
+import { InvalidEvent, ErrorEvent, FatalEvent, BuildEvent, ReadyEvent } from './interfaces';
+
+const prog = sade('sapper').version(pkg.version);
+
+if (process.argv[2] === 'start') {
+	// remove this in a future version
+	console.error(colors.bold.red(`'sapper start' has been removed`));
+	console.error(`Use 'node [build_dir]' instead`);
+	process.exit(1);
+}
+
+const start = Date.now();
+
+prog.command('dev')
+	.describe('Start a development server')
+	.option('-p, --port', 'Specify a port')
+	.option('-o, --open', 'Open a browser window')
+	.option('--dev-port', 'Specify a port for development server')
+	.option('--hot', 'Use hot module replacement (requires webpack)', true)
+	.option('--live', 'Reload on changes if not using --hot', true)
+	.option('--bundler', 'Specify a bundler (rollup or webpack)')
+	.option('--cwd', 'Current working directory', '.')
+	.option('--src', 'Source directory', 'src')
+	.option('--routes', 'Routes directory', 'src/routes')
+	.option('--static', 'Static files directory', 'static')
+	.option('--output', 'Sapper output directory', '__sapper__')
+	.option('--build-dir', 'Development build directory', '__sapper__/dev')
+	.action(async (opts: {
+		port: number,
+		open: boolean,
+		'dev-port': number,
+		live: boolean,
+		hot: boolean,
+		bundler?: 'rollup' | 'webpack',
+		cwd: string,
+		src: string,
+		routes: string,
+		static: string,
+		output: string,
+		'build-dir': string
+	}) => {
+		const { dev } = await import('./api/dev');
+
+		try {
+			const watcher = dev({
+				cwd: opts.cwd,
+				src: opts.src,
+				routes: opts.routes,
+				static: opts.static,
+				output: opts.output,
+				dest: opts['build-dir'],
+				port: opts.port,
+				'dev-port': opts['dev-port'],
+				live: opts.live,
+				hot: opts.hot,
+				bundler: opts.bundler
+			});
+
+			let first = true;
+
+			watcher.on('stdout', data => {
+				process.stdout.write(data);
+			});
+
+			watcher.on('stderr', data => {
+				process.stderr.write(data);
+			});
+
+			watcher.on('ready', async (event: ReadyEvent) => {
+				if (first) {
+					console.log(colors.bold.cyan(`> Listening on http://localhost:${event.port}`));
+					if (opts.open) {
+						const { exec } = await import('child_process');
+						exec(`open http://localhost:${event.port}`);
+					}
+					first = false;
+				}
+			});
+
+			watcher.on('invalid', (event: InvalidEvent) => {
+				const changed = event.changed.map(filename => path.relative(process.cwd(), filename)).join(', ');
+				console.log(`\n${colors.bold.cyan(changed)} changed. rebuilding...`);
+			});
+
+			watcher.on('error', (event: ErrorEvent) => {
+				console.log(colors.red(`✗ ${event.type}`));
+				console.log(colors.red(event.message));
+			});
+
+			watcher.on('fatal', (event: FatalEvent) => {
+				console.log(colors.bold.red(`> ${event.message}`));
+				if (event.log) console.log(event.log);
+			});
+
+			watcher.on('build', (event: BuildEvent) => {
+				if (event.errors.length) {
+					console.log(colors.bold.red(`✗ ${event.type}`));
+
+					event.errors.filter(e => !e.duplicate).forEach(error => {
+						if (error.file) console.log(colors.bold(error.file));
+						console.log(error.message);
+					});
+
+					const hidden = event.errors.filter(e => e.duplicate).length;
+					if (hidden > 0) {
+						console.log(`${hidden} duplicate ${hidden === 1 ? 'error' : 'errors'} hidden\n`);
+					}
+				} else if (event.warnings.length) {
+					console.log(colors.bold.yellow(`• ${event.type}`));
+
+					event.warnings.filter(e => !e.duplicate).forEach(warning => {
+						if (warning.file) console.log(colors.bold(warning.file));
+						console.log(warning.message);
+					});
+
+					const hidden = event.warnings.filter(e => e.duplicate).length;
+					if (hidden > 0) {
+						console.log(`${hidden} duplicate ${hidden === 1 ? 'warning' : 'warnings'} hidden\n`);
+					}
+				} else {
+					console.log(`${colors.bold.green(`✔ ${event.type}`)} ${colors.gray(`(${format_milliseconds(event.duration)})`)}`);
+				}
+			});
+		} catch (err) {
+			console.log(colors.bold.red(`> ${err.message}`));
+			process.exit(1);
+		}
+	});
+
+prog.command('build [dest]')
+	.describe('Create a production-ready version of your app')
+	.option('-p, --port', 'Default of process.env.PORT', '3000')
+	.option('--bundler', 'Specify a bundler (rollup or webpack, blank for auto)')
+	.option('--legacy', 'Create separate legacy build')
+	.option('--cwd', 'Current working directory', '.')
+	.option('--src', 'Source directory', 'src')
+	.option('--routes', 'Routes directory', 'src/routes')
+	.option('--output', 'Sapper output directory', '__sapper__')
+	.example(`build custom-dir -p 4567`)
+	.action(async (dest = '__sapper__/build', opts: {
+		port: string,
+		legacy: boolean,
+		bundler?: 'rollup' | 'webpack',
+		cwd: string,
+		src: string,
+		routes: string,
+		output: string
+	}) => {
+		console.log(`> Building...`);
+
+		try {
+			await _build(opts.bundler, opts.legacy, opts.cwd, opts.src, opts.routes, opts.output, dest);
+
+			const launcher = path.resolve(dest, 'index.js');
+
+			fs.writeFileSync(launcher, `
+				// generated by sapper build at ${new Date().toISOString()}
+				process.env.NODE_ENV = process.env.NODE_ENV || 'production';
+				process.env.PORT = process.env.PORT || ${opts.port || 3000};
+
+				console.log('Starting server on port ' + process.env.PORT);
+				require('./server/server.js');
+			`.replace(/^\t+/gm, '').trim());
+
+			console.error(`\n> Finished in ${elapsed(start)}. Type ${colors.bold.cyan(`node ${dest}`)} to run the app.`);
+		} catch (err) {
+			console.log(`${colors.bold.red(`> ${err.message}`)}`);
+			process.exit(1);
+		}
+	});
+
+prog.command('export [dest]')
+	.describe('Export your app as static files (if possible)')
+	.option('--build', '(Re)build app before exporting', true)
+	.option('--basepath', 'Specify a base path')
+	.option('--timeout', 'Milliseconds to wait for a page (--no-timeout to disable)', 5000)
+	.option('--legacy', 'Create separate legacy build')
+	.option('--bundler', 'Specify a bundler (rollup or webpack, blank for auto)')
+	.option('--cwd', 'Current working directory', '.')
+	.option('--src', 'Source directory', 'src')
+	.option('--routes', 'Routes directory', 'src/routes')
+	.option('--static', 'Static files directory', 'static')
+	.option('--output', 'Sapper output directory', '__sapper__')
+	.option('--build-dir', 'Intermediate build directory', '__sapper__/build')
+	.action(async (dest = '__sapper__/export', opts: {
+		build: boolean,
+		legacy: boolean,
+		bundler?: 'rollup' | 'webpack',
+		basepath?: string,
+		timeout: number | false,
+		cwd: string,
+		src: string,
+		routes: string,
+		static: string,
+		output: string,
+		'build-dir': string,
+	}) => {
+		try {
+			if (opts.build) {
+				console.log(`> Building...`);
+				await _build(opts.bundler, opts.legacy, opts.cwd, opts.src, opts.routes, opts.output, opts['build-dir']);
+				console.error(`\n> Built in ${elapsed(start)}`);
+			}
+
+			const { export: _export } = await import('./api/export');
+			const { default: pb } = await import('pretty-bytes');
+
+			await _export({
+				cwd: opts.cwd,
+				static: opts.static,
+				build_dir: opts['build-dir'],
+				export_dir: dest,
+				basepath: opts.basepath,
+				timeout: opts.timeout,
+
+				oninfo: event => {
+					console.log(colors.bold.cyan(`> ${event.message}`));
+				},
+
+				onfile: event => {
+					const size_color = event.size > 150000 ? colors.bold.red : event.size > 50000 ? colors.bold.yellow : colors.bold.gray;
+						const size_label = size_color(left_pad(pb(event.size), 10));
+
+						const file_label = event.status === 200
+							? event.file
+							: colors.bold[event.status >= 400 ? 'red' : 'yellow'](`(${event.status}) ${event.file}`);
+
+						console.log(`${size_label}   ${file_label}`);
+				}
+			});
+
+			console.error(`\n> Finished in ${elapsed(start)}. Type ${colors.bold.cyan(`npx serve ${dest}`)} to run the app.`);
+		} catch (err) {
+			console.error(colors.bold.red(`> ${err.message}`));
+			process.exit(1);
+		}
+	});
+
+prog.parse(process.argv);
+
+
+async function _build(
+	bundler: 'rollup' | 'webpack',
+	legacy: boolean,
+	cwd: string,
+	src: string,
+	routes: string,
+	output: string,
+	dest: string
+) {
+	const { build } = await import('./api/build');
+
+	await build({
+		bundler,
+		legacy,
+		cwd,
+		src,
+		routes,
+		dest,
+
+		oncompile: event => {
+			let banner = `built ${event.type}`;
+			let c = colors.cyan;
+
+			const { warnings } = event.result;
+			if (warnings.length > 0) {
+				banner += ` with ${warnings.length} ${warnings.length === 1 ? 'warning' : 'warnings'}`;
+				c = colors.yellow;
+			}
+
+			console.log();
+			console.log(c(`┌─${repeat('─', banner.length)}─┐`));
+			console.log(c(`│ ${colors.bold(banner)       } │`));
+			console.log(c(`└─${repeat('─', banner.length)}─┘`));
+
+			console.log(event.result.print());
+		}
+	});
+}
--- a/src/config/env.ts
+++ b/src/config/env.ts
@@ -0,0 +1,7 @@
+export let dev: boolean;
+export let src: string;
+export let dest: string;
+
+export const set_dev = (_: boolean) => dev = _;
+export const set_src = (_: string) => src = _;
+export const set_dest = (_: string) => dest = _;
--- a/src/config/rollup.ts
+++ b/src/config/rollup.ts
@@ -0,0 +1,53 @@
+import { dev, src, dest } from './env';
+
+export default {
+	dev,
+
+	client: {
+		input: () => {
+			return `${src}/client.js`
+		},
+
+		output: () => {
+			let dir = `${dest}/client`;
+			if (process.env.SAPPER_LEGACY_BUILD) dir += `/legacy`;
+
+			return {
+				dir,
+				entryFileNames: '[name].[hash].js',
+				chunkFileNames: '[name].[hash].js',
+				format: 'esm',
+				sourcemap: dev
+			};
+		}
+	},
+
+	server: {
+		input: () => {
+			return {
+				server: `${src}/server.js`
+			};
+		},
+
+		output: () => {
+			return {
+				dir: `${dest}/server`,
+				format: 'cjs',
+				sourcemap: dev
+			};
+		}
+	},
+
+	serviceworker: {
+		input: () => {
+			return `${src}/service-worker.js`;
+		},
+
+		output: () => {
+			return {
+				file: `${dest}/service-worker.js`,
+				format: 'iife'
+			}
+		}
+	}
+};
--- a/src/config/webpack.ts
+++ b/src/config/webpack.ts
@@ -0,0 +1,55 @@
+import { dev, src, dest } from './env';
+
+export default {
+	dev,
+
+	client: {
+		entry: () => {
+			return {
+				main: `${src}/client`
+			};
+		},
+
+		output: () => {
+			return {
+				path: `${dest}/client`,
+				filename: '[hash]/[name].js',
+				chunkFilename: '[hash]/[name].[id].js',
+				publicPath: `client/`
+			};
+		}
+	},
+
+	server: {
+		entry: () => {
+			return {
+				server: `${src}/server`
+			};
+		},
+
+		output: () => {
+			return {
+				path: `${dest}/server`,
+				filename: '[name].js',
+				chunkFilename: '[hash]/[name].[id].js',
+				libraryTarget: 'commonjs2'
+			};
+		}
+	},
+
+	serviceworker: {
+		entry: () => {
+			return {
+				'service-worker': `${src}/service-worker`
+			};
+		},
+
+		output: () => {
+			return {
+				path: dest,
+				filename: '[name].js',
+				chunkFilename: '[name].[id].[hash].js'
+			}
+		}
+	}
+};
--- a/src/core.ts
+++ b/src/core.ts
@@ -0,0 +1,3 @@
+export * from './core/create_manifests';
+export { default as create_compilers } from './core/create_compilers/index';
+export { default as create_manifest_data } from './core/create_manifest_data';
--- a/src/core/create_compilers/RollupCompiler.ts
+++ b/src/core/create_compilers/RollupCompiler.ts
@@ -0,0 +1,169 @@
+import * as path from 'path';
+import relative from 'require-relative';
+import { CompileResult } from './interfaces';
+import RollupResult from './RollupResult';
+
+let rollup: any;
+
+export default class RollupCompiler {
+	_: Promise<any>;
+	_oninvalid: (filename: string) => void;
+	_start: number;
+	input: string;
+	warnings: any[];
+	errors: any[];
+	chunks: any[];
+	css_files: Array<{ id: string, code: string }>;
+
+	constructor(config: any) {
+		this._ = this.get_config(config);
+		this.input = null;
+		this.warnings = [];
+		this.errors = [];
+		this.chunks = [];
+		this.css_files = [];
+	}
+
+	async get_config(mod: any) {
+		// TODO this is hacky, and doesn't need to apply to all three compilers
+		(mod.plugins || (mod.plugins = [])).push({
+			name: 'sapper-internal',
+			options: (opts: any) => {
+				this.input = opts.input;
+			},
+			renderChunk: (code: string, chunk: any) => {
+				this.chunks.push(chunk);
+			},
+			transform: (code: string, id: string) => {
+				if (/\.css$/.test(id)) {
+					this.css_files.push({ id, code });
+					return ``;
+				}
+			}
+		});
+
+		const onwarn = mod.onwarn || ((warning: any, handler: (warning: any) => void) => {
+			handler(warning);
+		});
+
+		mod.onwarn = (warning: any) => {
+			onwarn(warning, (warning: any) => {
+				this.warnings.push(warning);
+			});
+		};
+
+		return mod;
+	}
+
+	oninvalid(cb: (filename: string) => void) {
+		this._oninvalid = cb;
+	}
+
+	async compile(): Promise<CompileResult> {
+		const config = await this._;
+
+		const start = Date.now();
+
+		try {
+			const bundle = await rollup.rollup(config);
+			await bundle.write(config.output);
+
+			return new RollupResult(Date.now() - start, this);
+		} catch (err) {
+			if (err.filename) {
+				// TODO this is a bit messy. Also, can
+				// Rollup emit other kinds of error?
+				err.message = [
+					`Failed to build — error in ${err.filename}: ${err.message}`,
+					err.frame
+				].filter(Boolean).join('\n');
+			}
+
+			throw err;
+		}
+	}
+
+	async watch(cb: (err?: Error, stats?: any) => void) {
+		const config = await this._;
+
+		const watcher = rollup.watch(config);
+
+		watcher.on('change', (id: string) => {
+			this.chunks = [];
+			this.warnings = [];
+			this.errors = [];
+			this._oninvalid(id);
+		});
+
+		watcher.on('event', (event: any) => {
+			switch (event.code) {
+				case 'FATAL':
+					// TODO kill the process?
+					if (event.error.filename) {
+						// TODO this is a bit messy. Also, can
+						// Rollup emit other kinds of error?
+						event.error.message = [
+							`Failed to build — error in ${event.error.filename}: ${event.error.message}`,
+							event.error.frame
+						].filter(Boolean).join('\n');
+					}
+
+					cb(event.error);
+					break;
+
+				case 'ERROR':
+					this.errors.push(event.error);
+					cb(null, new RollupResult(Date.now() - this._start, this));
+					break;
+
+				case 'START':
+				case 'END':
+					// TODO is there anything to do with this info?
+					break;
+
+				case 'BUNDLE_START':
+					this._start = Date.now();
+					break;
+
+				case 'BUNDLE_END':
+					cb(null, new RollupResult(Date.now() - this._start, this));
+					break;
+
+				default:
+					console.log(`Unexpected event ${event.code}`);
+			}
+		});
+	}
+
+	static async load_config(cwd: string) {
+		if (!rollup) rollup = relative('rollup', cwd);
+
+		const input = path.resolve(cwd, 'rollup.config.js');
+
+		const bundle = await rollup.rollup({
+			input,
+			inlineDynamicImports: true,
+			external: (id: string) => {
+				return (id[0] !== '.' && !path.isAbsolute(id)) || id.slice(-5, id.length) === '.json';
+			}
+		});
+
+		const resp = await bundle.generate({ format: 'cjs' });
+		const { code } = resp.output ? resp.output[0] : resp;
+
+		// temporarily override require
+		const defaultLoader = require.extensions['.js'];
+		require.extensions['.js'] = (module: any, filename: string) => {
+			if (filename === input) {
+				module._compile(code, filename);
+			} else {
+				defaultLoader(module, filename);
+			}
+		};
+
+		const config: any = require(input);
+		delete require.cache[input];
+
+		return config;
+	}
+}
--- a/src/core/create_compilers/RollupResult.ts
+++ b/src/core/create_compilers/RollupResult.ts
@@ -0,0 +1,118 @@
+import * as path from 'path';
+import colors from 'kleur';
+import pb from 'pretty-bytes';
+import RollupCompiler from './RollupCompiler';
+import extract_css from './extract_css';
+import { left_pad } from '../../utils';
+import { CompileResult, BuildInfo, CompileError, Chunk, CssFile } from './interfaces';
+import { ManifestData, Dirs } from '../../interfaces';
+
+export default class RollupResult implements CompileResult {
+	duration: number;
+	errors: CompileError[];
+	warnings: CompileError[];
+	chunks: Chunk[];
+	assets: Record<string, string>;
+	css_files: CssFile[];
+	css: {
+		main: string,
+		chunks: Record<string, string[]>
+	};
+	summary: string;
+
+	constructor(duration: number, compiler: RollupCompiler) {
+		this.duration = duration;
+
+		this.errors = compiler.errors.map(munge_warning_or_error);
+		this.warnings = compiler.warnings.map(munge_warning_or_error); // TODO emit this as they happen
+
+		this.chunks = compiler.chunks.map(chunk => ({
+			file: chunk.fileName,
+			imports: chunk.imports.filter(Boolean),
+			modules: Object.keys(chunk.modules)
+		}));
+
+		this.css_files = compiler.css_files;
+
+		// TODO populate this properly. We don't have named chunks, as in
+		// webpack, but we can have a route -> [chunk] map or something
+		this.assets = {};
+
+		if (typeof compiler.input === 'string') {
+			compiler.chunks.forEach(chunk => {
+				if (compiler.input in chunk.modules) {
+					this.assets.main = chunk.fileName;
+				}
+			});
+		} else {
+			for (const name in compiler.input) {
+				const file = compiler.input[name];
+				this.assets[name] = compiler.chunks.find(chunk => file in chunk.modules).fileName;
+			}
+		}
+
+		this.summary = compiler.chunks.map(chunk => {
+			const size_color = chunk.code.length > 150000 ? colors.bold.red : chunk.code.length > 50000 ? colors.bold.yellow : colors.bold.white;
+			const size_label = left_pad(pb(chunk.code.length), 10);
+
+			const lines = [size_color(`${size_label} ${chunk.fileName}`)];
+
+			const deps = Object.keys(chunk.modules)
+				.map(file => {
+					return {
+						file: path.relative(process.cwd(), file),
+						size: chunk.modules[file].renderedLength
+					};
+				})
+				.filter(dep => dep.size > 0)
+				.sort((a, b) => b.size - a.size);
+
+			const total_unminified = deps.reduce((t, d) => t + d.size, 0);
+
+			deps.forEach((dep, i) => {
+				const c = i === deps.length - 1 ? '└' : '│';
+				let line = `           ${c} ${dep.file}`;
+
+				if (deps.length > 1) {
+					const p = (100 * dep.size / total_unminified).toFixed(1);
+					line += ` (${p}%)`;
+				}
+
+				lines.push(colors.gray(line));
+			});
+
+			return lines.join('\n');
+		}).join('\n');
+	}
+
+	to_json(manifest_data: ManifestData, dirs: Dirs): BuildInfo {
+		// TODO extract_css has side-effects that don't belong
+		// in a method called to_json
+		return {
+			bundler: 'rollup',
+			shimport: require('shimport/package.json').version,
+			assets: this.assets,
+			css: extract_css(this, manifest_data.components, dirs)
+		};
+	}
+
+	print() {
+		const blocks: string[] = this.warnings.map(warning => {
+			return warning.file
+				? `> ${colors.bold(warning.file)}\n${warning.message}`
+				: `> ${warning.message}`;
+		});
+
+		blocks.push(this.summary);
+
+		return blocks.join('\n\n');
+	}
+}
+
+function munge_warning_or_error(warning_or_error: any) {
+	return {
+		file: warning_or_error.filename,
+		message: [warning_or_error.message, warning_or_error.frame].filter(Boolean).join('\n')
+	};
+}
+
--- a/src/core/create_compilers/WebpackCompiler.ts
+++ b/src/core/create_compilers/WebpackCompiler.ts
@@ -0,0 +1,46 @@
+import relative from 'require-relative';
+import { CompileResult } from './interfaces';
+import WebpackResult from './WebpackResult';
+
+let webpack: any;
+
+export class WebpackCompiler {
+	_: any;
+
+	constructor(config: any) {
+		if (!webpack) webpack = relative('webpack', process.cwd());
+		this._ = webpack(config);
+	}
+
+	oninvalid(cb: (filename: string) => void) {
+		this._.hooks.invalid.tap('sapper', cb);
+	}
+
+	compile(): Promise<CompileResult> {
+		return new Promise((fulfil, reject) => {
+			this._.run((err: Error, stats: any) => {
+				if (err) {
+					reject(err);
+					process.exit(1);
+				}
+
+				const result = new WebpackResult(stats);
+
+				if (result.errors.length) {
+					console.error(stats.toString({ colors: true }));
+					reject(new Error(`Encountered errors while building app`));
+				}
+
+				else {
+					fulfil(result);
+				}
+			});
+		});
+	}
+
+	watch(cb: (err?: Error, stats?: any) => void) {
+		this._.watch({}, (err?: Error, stats?: any) => {
+			cb(err, stats && new WebpackResult(stats));
+		});
+	}
+}
--- a/src/core/create_compilers/WebpackResult.ts
+++ b/src/core/create_compilers/WebpackResult.ts
@@ -0,0 +1,84 @@
+import format_messages from 'webpack-format-messages';
+import { CompileResult, BuildInfo, CompileError, Chunk, CssFile } from './interfaces';
+import { ManifestData, Dirs } from '../../interfaces';
+
+const locPattern = /\((\d+):(\d+)\)$/;
+
+function munge_warning_or_error(message: string) {
+	// TODO this is all a bit rube goldberg...
+	const lines = message.split('\n');
+
+	const file = lines.shift()
+		.replace('[7m', '') // careful — there is a special character at the beginning of this string
+		.replace('[27m', '')
+		.replace('./', '');
+
+	let line = null;
+	let column = null;
+
+	const match = locPattern.exec(lines[0]);
+	if (match) {
+		lines[0] = lines[0].replace(locPattern, '');
+		line = +match[1];
+		column = +match[2];
+	}
+
+	return {
+		file,
+		message: lines.join('\n')
+	};
+}
+
+export default class WebpackResult implements CompileResult {
+	duration: number;
+	errors: CompileError[];
+	warnings: CompileError[];
+	chunks: Chunk[];
+	assets: Record<string, string>;
+	css_files: CssFile[];
+	stats: any;
+
+	constructor(stats: any) {
+		this.stats = stats;
+
+		const info = stats.toJson();
+
+		const messages = format_messages(stats);
+
+		this.errors = messages.errors.map(munge_warning_or_error);
+		this.warnings = messages.warnings.map(munge_warning_or_error);
+
+		this.duration = info.time;
+
+		this.chunks = info.assets.map((chunk: { name: string }) => ({ file: chunk.name }));
+		this.assets = info.assetsByChunkName;
+	}
+
+	to_json(manifest_data: ManifestData, dirs: Dirs): BuildInfo {
+		const extract_css = (assets: string[] | string) => {
+			assets = Array.isArray(assets) ? assets : [assets];
+			return assets.find(asset => /\.css$/.test(asset));
+		};
+
+		return {
+			bundler: 'webpack',
+			shimport: null, // webpack has its own loader
+			assets: this.assets,
+			css: {
+				main: extract_css(this.assets.main),
+				chunks: Object
+					.keys(this.assets)
+					.filter(chunkName => chunkName !== 'main')
+					.reduce((chunks: { [key: string]: string }, chukName) => {
+						const assets = this.assets[chukName];
+						chunks[chukName] = extract_css(assets);
+						return chunks;
+					}, {})
+			}
+		};
+	}
+
+	print() {
+		return this.stats.toString({ colors: true });
+	}
+}
--- a/src/core/create_compilers/extract_css.ts
+++ b/src/core/create_compilers/extract_css.ts
@@ -0,0 +1,243 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import hash from 'string-hash';
+import * as codec from 'sourcemap-codec';
+import { PageComponent, Dirs } from '../../interfaces';
+import { CompileResult, Chunk } from './interfaces';
+import { posixify } from '../../utils'
+
+const inline_sourcemap_header = 'data:application/json;charset=utf-8;base64,';
+
+function extract_sourcemap(raw: string, id: string) {
+	let raw_map: string;
+	let map = null;
+
+	const code = raw.replace(/\/\*#\s+sourceMappingURL=(.+)\s+\*\//g, (m, url) => {
+		if (raw_map) {
+			// TODO should not happen!
+			throw new Error(`Found multiple sourcemaps in single CSS file (${id})`);
+		}
+
+		raw_map = url;
+		return '';
+	}).trim();
+
+	if (raw_map) {
+		if (raw_map.startsWith(inline_sourcemap_header)) {
+			const json = Buffer.from(raw_map.slice(inline_sourcemap_header.length), 'base64').toString();
+			map = JSON.parse(json);
+		} else {
+			// TODO do we want to handle non-inline sourcemaps? could be a rabbit hole
+		}
+	}
+
+	return {
+		code,
+		map
+	};
+}
+
+type SourceMap = {
+	version: 3;
+	file: string;
+	sources: string[];
+	sourcesContent: string[];
+	names: string[];
+	mappings: string;
+};
+
+function get_css_from_modules(modules: string[], css_map: Map<string, string>, dirs: Dirs) {
+	const parts: string[] = [];
+	const mappings: number[][][] = [];
+
+	const combined_map: SourceMap = {
+		version: 3,
+		file: null,
+		sources: [],
+		sourcesContent: [],
+		names: [],
+		mappings: null
+	};
+
+	modules.forEach(module => {
+		if (!/\.css$/.test(module)) return;
+
+		const css = css_map.get(module);
+
+		const { code, map } = extract_sourcemap(css, module);
+
+		parts.push(code);
+
+		if (map) {
+			const lines = codec.decode(map.mappings);
+
+			if (combined_map.sources.length > 0 || combined_map.names.length > 0) {
+				lines.forEach(line => {
+					line.forEach(segment => {
+						// adjust source index
+						segment[1] += combined_map.sources.length;
+
+						// adjust name index
+						if (segment[4]) segment[4] += combined_map.names.length;
+					});
+				});
+			}
+
+			combined_map.sources.push(...map.sources);
+			combined_map.sourcesContent.push(...map.sourcesContent);
+			combined_map.names.push(...map.names);
+
+			mappings.push(...lines);
+		}
+	});
+
+	if (parts.length > 0) {
+		combined_map.mappings = codec.encode(mappings);
+
+		combined_map.sources = combined_map.sources.map(source => path.relative(`${dirs.dest}/client`, source));
+
+		return {
+			code: parts.join('\n'),
+			map: combined_map
+		};
+	}
+
+	return null;
+}
+
+export default function extract_css(client_result: CompileResult, components: PageComponent[], dirs: Dirs) {
+	const result: {
+		main: string | null;
+		chunks: Record<string, string[]>
+	} = {
+		main: null,
+		chunks: {}
+	};
+
+	if (!client_result.css_files) return; // Rollup-only for now
+
+	let asset_dir = `${dirs.dest}/client`;
+	if (process.env.SAPPER_LEGACY_BUILD) asset_dir += '/legacy';
+
+	const unclaimed = new Set(client_result.css_files.map(x => x.id));
+
+	const lookup = new Map();
+	client_result.chunks.forEach(chunk => {
+		lookup.set(chunk.file, chunk);
+	});
+
+	const css_map = new Map();
+	client_result.css_files.forEach(css_module => {
+		css_map.set(css_module.id, css_module.code);
+	});
+
+	const chunks_with_css = new Set();
+
+	// concatenate and emit CSS
+	client_result.chunks.forEach(chunk => {
+		const css_modules = chunk.modules.filter(m => css_map.has(m));
+		if (!css_modules.length) return;
+
+		const css = get_css_from_modules(css_modules, css_map, dirs);
+
+		const { code, map } = css;
+
+		const output_file_name = chunk.file.replace(/\.js$/, '.css');
+
+		map.file = output_file_name;
+		map.sources = map.sources.map(source => path.relative(`${asset_dir}`, source));
+
+		fs.writeFileSync(`${asset_dir}/${output_file_name}`, `${code}\n/* sourceMappingURL=./${output_file_name}.map */`);
+		fs.writeFileSync(`${asset_dir}/${output_file_name}.map`, JSON.stringify(map, null, '  '));
+
+		chunks_with_css.add(chunk);
+	});
+
+	const entry = path.resolve(dirs.src, 'client.js');
+	const entry_chunk = client_result.chunks.find(chunk => chunk.modules.indexOf(entry) !== -1);
+
+	const entry_chunk_dependencies: Set<Chunk> = new Set([entry_chunk]);
+	const entry_css_modules: string[] = [];
+
+	// recursively find the chunks this component depends on
+	entry_chunk_dependencies.forEach(chunk => {
+		chunk.imports.forEach(file => {
+			entry_chunk_dependencies.add(lookup.get(file));
+		});
+
+		if (chunks_with_css.has(chunk)) {
+			chunk.modules.forEach(file => {
+				unclaimed.delete(file);
+				if (css_map.has(file)) {
+					entry_css_modules.push(file);
+				}
+			});
+		}
+	});
+
+	// figure out which (css-having) chunks each component depends on
+	components.forEach(component => {
+		const resolved = path.resolve(dirs.routes, component.file);
+		const chunk: Chunk = client_result.chunks.find(chunk => chunk.modules.indexOf(resolved) !== -1);
+
+		if (!chunk) {
+			// this should never happen!
+			throw new Error(`Could not find chunk that owns ${component.file}`);
+		}
+
+		const chunk_dependencies: Set<Chunk> = new Set([chunk]);
+		const css_dependencies: string[] = [];
+
+		// recursively find the chunks this component depends on
+		chunk_dependencies.forEach(chunk => {
+			chunk.imports.forEach(file => {
+				chunk_dependencies.add(lookup.get(file));
+			});
+
+			if (chunks_with_css.has(chunk)) {
+				css_dependencies.push(chunk.file.replace(/\.js$/, '.css'));
+
+				chunk.modules.forEach(file => {
+					unclaimed.delete(file);
+				});
+			}
+		});
+
+		result.chunks[component.file] = css_dependencies;
+	});
+
+	fs.readdirSync(asset_dir).forEach(file => {
+		if (fs.statSync(`${asset_dir}/${file}`).isDirectory()) return;
+
+		const source = fs.readFileSync(`${asset_dir}/${file}`, 'utf-8');
+
+		const replaced = source.replace(/["']__SAPPER_CSS_PLACEHOLDER:(.+?)__["']/g, (m, route) => {
+			return JSON.stringify(result.chunks[route]);
+		});
+
+		fs.writeFileSync(`${asset_dir}/${file}`, replaced);
+	});
+
+	unclaimed.forEach(file => {
+		entry_css_modules.push(file);
+	});
+
+	const leftover = get_css_from_modules(entry_css_modules, css_map, dirs);
+	if (leftover) {
+		const { code, map } = leftover;
+
+		const main_hash = hash(code);
+
+		const output_file_name = `main.${main_hash}.css`;
+
+		map.file = output_file_name;
+		map.sources = map.sources.map(source => path.relative(asset_dir, source));
+
+		fs.writeFileSync(`${asset_dir}/${output_file_name}`, `${code}\n/* sourceMappingURL=client/${output_file_name}.map */`);
+		fs.writeFileSync(`${asset_dir}/${output_file_name}.map`, JSON.stringify(map, null, '  '));
+
+		result.main = output_file_name;
+	}
+
+	return result;
+}
--- a/src/core/create_compilers/index.ts
+++ b/src/core/create_compilers/index.ts
@@ -0,0 +1,72 @@
+import * as path from 'path';
+import RollupCompiler from './RollupCompiler';
+import { WebpackCompiler } from './WebpackCompiler';
+import { set_dev, set_src, set_dest } from '../../config/env';
+
+export type Compiler = RollupCompiler | WebpackCompiler;
+
+export type Compilers = {
+	client: Compiler;
+	server: Compiler;
+	serviceworker?: Compiler;
+}
+
+export default async function create_compilers(
+	bundler: 'rollup' | 'webpack',
+	cwd: string,
+	src: string,
+	dest: string,
+	dev: boolean
+): Promise<Compilers> {
+	set_dev(dev);
+	set_src(src);
+	set_dest(dest);
+
+	if (bundler === 'rollup') {
+		const config = await RollupCompiler.load_config(cwd);
+		validate_config(config, 'rollup');
+
+		normalize_rollup_config(config.client);
+		normalize_rollup_config(config.server);
+
+		if (config.serviceworker) {
+			normalize_rollup_config(config.serviceworker);
+		}
+
+		return {
+			client: new RollupCompiler(config.client),
+			server: new RollupCompiler(config.server),
+			serviceworker: config.serviceworker && new RollupCompiler(config.serviceworker)
+		};
+	}
+
+	if (bundler === 'webpack') {
+		const config = require(path.resolve(cwd, 'webpack.config.js'));
+		validate_config(config, 'webpack');
+
+		return {
+			client: new WebpackCompiler(config.client),
+			server: new WebpackCompiler(config.server),
+			serviceworker: config.serviceworker && new WebpackCompiler(config.serviceworker)
+		};
+	}
+
+	// this shouldn't be possible...
+	throw new Error(`Invalid bundler option '${bundler}'`);
+}
+
+function validate_config(config: any, bundler: 'rollup' | 'webpack') {
+	if (!config.client || !config.server) {
+		throw new Error(`${bundler}.config.js must export a { client, server, serviceworker? } object`);
+	}
+}
+
+function normalize_rollup_config(config: any) {
+	if (typeof config.input === 'string') {
+		config.input = path.normalize(config.input);
+	} else {
+		for (const name in config.input) {
+			config.input[name] = path.normalize(config.input[name]);
+		}
+	}
+}
--- a/src/core/create_compilers/interfaces.ts
+++ b/src/core/create_compilers/interfaces.ts
@@ -0,0 +1,39 @@
+import { ManifestData, Dirs } from '../../interfaces';
+
+export type Chunk = {
+	file: string;
+	imports: string[];
+	modules: string[];
+}
+
+export type CssFile = {
+	id: string;
+	code: string;
+};
+
+export class CompileError {
+	file: string;
+	message: string;
+}
+
+export interface CompileResult {
+	duration: number;
+	errors: CompileError[];
+	warnings: CompileError[];
+	chunks: Chunk[];
+	assets: Record<string, string>;
+	css_files: CssFile[];
+
+	to_json: (manifest_data: ManifestData, dirs: Dirs) => BuildInfo
+}
+
+export type BuildInfo = {
+	bundler: string;
+	shimport: string;
+	assets: Record<string, string>;
+	legacy_assets?: Record<string, string>;
+	css: {
+		main: string | null,
+		chunks: Record<string, string[]>
+	}
+}
--- a/src/core/create_manifest_data.ts
+++ b/src/core/create_manifest_data.ts
@@ -0,0 +1,306 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import { Page, PageComponent, ServerRoute, ManifestData } from '../interfaces';
+import { posixify, reserved_words } from '../utils';
+
+export default function create_manifest_data(cwd: string): ManifestData {
+	// TODO remove in a future version
+	if (!fs.existsSync(cwd)) {
+		throw new Error(`As of Sapper 0.21, the routes/ directory should become src/routes/`);
+	}
+
+	const components: PageComponent[] = [];
+	const pages: Page[] = [];
+	const server_routes: ServerRoute[] = [];
+
+	const default_layout: PageComponent = {
+		default: true,
+		name: '_default_layout',
+		file: null
+	};
+
+	function walk(
+		dir: string,
+		parent_segments: Part[][],
+		parent_params: string[],
+		stack: Array<{
+			component: PageComponent,
+			params: string[]
+		}>
+	) {
+		const items = fs.readdirSync(dir)
+			.map(basename => {
+				const resolved = path.join(dir, basename);
+				const file = path.relative(cwd, resolved);
+				const is_dir = fs.statSync(resolved).isDirectory();
+
+				const ext = path.extname(basename);
+				if (!is_dir && !/^\.[a-z]+$/i.test(ext)) return null; // filter out tmp files etc
+
+				const segment = is_dir
+					? basename
+					: basename.slice(0, -path.extname(basename).length);
+
+				const parts = get_parts(segment);
+				const is_index = is_dir ? false : basename.startsWith('index.');
+				const is_page = ext === '.html';
+
+				parts.forEach(part => {
+					if (/\]\[/.test(part.content)) {
+						throw new Error(`Invalid route ${file} — parameters must be separated`);
+					}
+
+					if (part.qualifier && /[\(\)\?\:]/.test(part.qualifier.slice(1, -1))) {
+						throw new Error(`Invalid route ${file} — cannot use (, ), ? or : in route qualifiers`);
+					}
+				});
+
+				return {
+					basename,
+					parts,
+					file: posixify(file),
+					is_dir,
+					is_index,
+					is_page
+				};
+			})
+			.filter(Boolean)
+			.sort(comparator);
+
+		items.forEach(item => {
+			if (item.basename[0] === '_') return;
+
+			if (item.basename[0] === '.') {
+				if (item.file !== '.well-known') return;
+			}
+
+			const segments = parent_segments.slice();
+
+			if (item.is_index && segments.length > 0) {
+				const last_segment = segments[segments.length - 1].slice();
+				const suffix = item.basename
+					.slice(0, -path.extname(item.basename).length).
+					replace('index', '');
+
+				if (suffix) {
+					const last_part = last_segment[last_segment.length - 1];
+					if (last_part.dynamic) {
+						last_segment.push({ dynamic: false, content: suffix });
+					} else {
+						last_segment[last_segment.length - 1] = {
+							dynamic: false,
+							content: `${last_part.content}${suffix}`
+						};
+					}
+
+					segments[segments.length - 1] = last_segment;
+				}
+			} else {
+				segments.push(item.parts);
+			}
+
+			const params = parent_params.slice();
+			params.push(...item.parts.filter(p => p.dynamic).map(p => p.content));
+
+			if (item.is_dir) {
+				const index = path.join(dir, item.basename, '_layout.html');
+
+				const component = fs.existsSync(index) && {
+					name: `${get_slug(item.file)}__layout`,
+					file: `${item.file}/_layout.html`
+				};
+
+				if (component) components.push(component);
+
+				walk(
+					path.join(dir, item.basename),
+					segments,
+					params,
+					component
+						? stack.concat({ component, params })
+						: stack.concat(null)
+				);
+			}
+
+			else if (item.is_page) {
+				const component = {
+					name: get_slug(item.file),
+					file: item.file
+				};
+
+				const parts = stack.concat({
+					component,
+					params
+				});
+
+				components.push(component);
+				if (item.basename === 'index.html') {
+					pages.push({
+						pattern: get_pattern(parent_segments, true),
+						parts
+					});
+				} else {
+					pages.push({
+						pattern: get_pattern(segments, true),
+						parts
+					});
+				}
+			}
+
+			else {
+				server_routes.push({
+					name: `route_${get_slug(item.file)}`,
+					pattern: get_pattern(segments, false),
+					file: item.file,
+					params: params
+				});
+			}
+		});
+	}
+
+	const root_file = path.join(cwd, '_layout.html');
+	const root = fs.existsSync(root_file)
+		? {
+			name: 'main',
+			file: '_layout.html'
+		}
+		: default_layout;
+
+	walk(cwd, [], [], []);
+
+	// check for clashes
+	const seen_pages: Map<string, Page> = new Map();
+	pages.forEach(page => {
+		const pattern = page.pattern.toString();
+		if (seen_pages.has(pattern)) {
+			const file = page.parts.pop().component.file;
+			const other_page = seen_pages.get(pattern);
+			const other_file = other_page.parts.pop().component.file;
+
+			throw new Error(`The ${other_file} and ${file} pages clash`);
+		}
+
+		seen_pages.set(pattern, page);
+	});
+
+	const seen_routes: Map<string, ServerRoute> = new Map();
+	server_routes.forEach(route => {
+		const pattern = route.pattern.toString();
+		if (seen_routes.has(pattern)) {
+			const other_route = seen_routes.get(pattern);
+			throw new Error(`The ${other_route.file} and ${route.file} routes clash`);
+		}
+
+		seen_routes.set(pattern, route);
+	});
+
+	return {
+		root,
+		components,
+		pages,
+		server_routes
+	};
+}
+
+type Part = {
+	content: string;
+	dynamic: boolean;
+	qualifier?: string;
+};
+
+function comparator(
+	a: { basename: string, parts: Part[], file: string, is_index: boolean },
+	b: { basename: string, parts: Part[], file: string, is_index: boolean }
+) {
+	if (a.is_index !== b.is_index) return a.is_index ? -1 : 1;
+
+	const max = Math.max(a.parts.length, b.parts.length);
+
+	for (let i = 0; i < max; i += 1) {
+		const a_sub_part = a.parts[i];
+		const b_sub_part = b.parts[i];
+
+		if (!a_sub_part) return 1; // b is more specific, so goes first
+		if (!b_sub_part) return -1;
+
+		if (a_sub_part.dynamic !== b_sub_part.dynamic) {
+			return a_sub_part.dynamic ? 1 : -1;
+		}
+
+		if (!a_sub_part.dynamic && a_sub_part.content !== b_sub_part.content) {
+			return (
+				(b_sub_part.content.length - a_sub_part.content.length) ||
+				(a_sub_part.content < b_sub_part.content ? -1 : 1)
+			);
+		}
+
+		// If both parts dynamic, check for regexp patterns
+		if (a_sub_part.dynamic && b_sub_part.dynamic) {
+			const regexp_pattern = /\((.*?)\)/;
+			const a_match = regexp_pattern.exec(a_sub_part.content);
+			const b_match = regexp_pattern.exec(b_sub_part.content);
+
+			if (!a_match && b_match) {
+				return 1; // No regexp, so less specific than b
+			}
+			if (!b_match && a_match) {
+				return -1;
+			}
+			if (a_match && b_match && a_match[1] !== b_match[1]) {
+				return b_match[1].length - a_match[1].length;
+			}
+		}
+	}
+}
+
+function get_parts(part: string): Part[] {
+	return part.split(/\[(.+)\]/)
+		.map((str, i) => {
+			if (!str) return null;
+			const dynamic = i % 2 === 1;
+
+			const [, content, qualifier] = dynamic
+				? /([^(]+)(\(.+\))?$/.exec(str)
+				: [, str, null];
+
+			return {
+				content,
+				dynamic,
+				qualifier
+			};
+		})
+		.filter(Boolean);
+}
+
+function get_slug(file: string) {
+	let name = file
+		.replace(/[\\\/]index/, '')
+		.replace(/_default([\/\\index])?\.html$/, 'index')
+		.replace(/[\/\\]/g, '_')
+		.replace(/\.\w+$/, '')
+		.replace(/\[([^(]+)(?:\([^(]+\))?\]/, '$$$1')
+		.replace(/[^a-zA-Z0-9_$]/g, c => {
+			return c === '.' ? '_' : `$${c.charCodeAt(0)}`
+		});
+
+	if (reserved_words.has(name)) name += '_';
+	return name;
+}
+
+function get_pattern(segments: Part[][], add_trailing_slash: boolean) {
+	return new RegExp(
+		`^` +
+		segments.map(segment => {
+			return '\\/' + segment.map(part => {
+				return part.dynamic
+					? part.qualifier || '([^\\/]+?)'
+					: encodeURI(part.content.normalize())
+						.replace(/\?/g, '%3F')
+						.replace(/#/g, '%23')
+						.replace(/%5B/g, '[')
+						.replace(/%5D/g, ']');
+			}).join('');
+		}).join('') +
+		(add_trailing_slash ? '\\\/?$' : '$')
+	);
+}
--- a/src/core/create_manifests.ts
+++ b/src/core/create_manifests.ts
@@ -0,0 +1,243 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import { posixify, stringify, walk, write_if_changed } from '../utils';
+import { Page, PageComponent, ManifestData } from '../interfaces';
+
+export function create_main_manifests({
+	bundler,
+	manifest_data,
+	dev_port,
+	dev,
+	cwd,
+	src,
+	dest,
+	routes,
+	output
+}: {
+	bundler: string,
+	manifest_data: ManifestData;
+	dev_port?: number;
+	dev: boolean;
+	cwd: string;
+	src: string;
+	dest: string;
+	routes: string;
+	output: string
+}) {
+	if (!fs.existsSync(output)) fs.mkdirSync(output);
+
+	const path_to_routes = path.relative(output, routes);
+
+	const client_manifest = generate_client(manifest_data, path_to_routes, bundler, dev, dev_port);
+	const server_manifest = generate_server(manifest_data, path_to_routes, cwd, src, dest, dev);
+
+	write_if_changed(
+		`${output}/_layout.html`,
+		`<svelte:component this={child.component} {...child.props}/>`
+	);
+	write_if_changed(`${output}/client.js`, client_manifest);
+	write_if_changed(`${output}/server.js`, server_manifest);
+}
+
+export function create_serviceworker_manifest({ manifest_data, output, client_files, static_files }: {
+	manifest_data: ManifestData;
+	output: string;
+	client_files: string[];
+	static_files: string;
+}) {
+	let files: string[] = ['/service-worker-index.html'];
+
+	if (fs.existsSync(static_files)) {
+		files = files.concat(walk(static_files));
+	} else {
+		// TODO remove in a future version
+		if (fs.existsSync('assets')) {
+			throw new Error(`As of Sapper 0.21, the assets/ directory should become static/`);
+		}
+	}
+
+	let code = `
+		// This file is generated by Sapper — do not edit it!
+		export const timestamp = ${Date.now()};
+
+		export const files = [\n\t${files.map((x: string) => stringify(x)).join(',\n\t')}\n];
+		export { files as assets }; // legacy
+
+		export const shell = [\n\t${client_files.map((x: string) => stringify(x)).join(',\n\t')}\n];
+
+		export const routes = [\n\t${manifest_data.pages.map((r: Page) => `{ pattern: ${r.pattern} }`).join(',\n\t')}\n];
+	`.replace(/^\t\t/gm, '').trim();
+
+	write_if_changed(`${output}/service-worker.js`, code);
+}
+
+function generate_client(
+	manifest_data: ManifestData,
+	path_to_routes: string,
+	bundler: string,
+	dev: boolean,
+	dev_port?: number
+) {
+	const template_file = path.resolve(__dirname, '../templates/client.js');
+	const template = fs.readFileSync(template_file, 'utf-8');
+
+	const page_ids = new Set(manifest_data.pages.map(page =>
+		page.pattern.toString()));
+
+	const server_routes_to_ignore = manifest_data.server_routes.filter(route =>
+		!page_ids.has(route.pattern.toString()));
+
+	const component_indexes: Record<string, number> = {};
+
+	const components = `[
+		${manifest_data.components.map((component, i) => {
+			const annotation = bundler === 'webpack'
+				? `/* webpackChunkName: "${component.name}" */ `
+				: '';
+
+			const source = get_file(path_to_routes, component);
+
+			component_indexes[component.name] = i;
+
+			return `{
+			js: () => import(${annotation}${stringify(source)}),
+			css: "__SAPPER_CSS_PLACEHOLDER:${stringify(component.file, false)}__"
+		}`;
+		}).join(',\n\t\t')}
+	]`.replace(/^\t/gm, '').trim();
+
+	let needs_decode = false;
+
+	let pages = `[
+		${manifest_data.pages.map(page => `{
+			// ${page.parts[page.parts.length - 1].component.file}
+			pattern: ${page.pattern},
+			parts: [
+				${page.parts.map(part => {
+					if (part === null) return 'null';
+
+					if (part.params.length > 0) {
+						needs_decode = true;
+						const props = part.params.map((param, i) => `${param}: d(match[${i + 1}])`);
+						return `{ i: ${component_indexes[part.component.name]}, params: match => ({ ${props.join(', ')} }) }`;
+					}
+
+					return `{ i: ${component_indexes[part.component.name]} }`;
+				}).join(',\n\t\t\t\t')}
+			]
+		}`).join(',\n\n\t\t')}
+	]`.replace(/^\t/gm, '').trim();
+
+	if (needs_decode) {
+		pages = `(d => ${pages})(decodeURIComponent)`
+	}
+
+	let footer = '';
+
+	if (dev) {
+		const sapper_dev_client = posixify(
+			path.resolve(__dirname, '../sapper-dev-client.js')
+		);
+
+		footer = `
+
+			if (typeof window !== 'undefined') {
+				import(${stringify(sapper_dev_client)}).then(client => {
+					client.connect(${dev_port});
+				});
+			}`.replace(/^\t{3}/gm, '');
+	}
+
+	return `// This file is generated by Sapper — do not edit it!\n` + template
+		.replace('__ROOT__', stringify(get_file(path_to_routes, manifest_data.root), false))
+		.replace('__ERROR__', stringify(posixify(`${path_to_routes}/_error.html`), false))
+		.replace('__IGNORE__', `[${server_routes_to_ignore.map(route => route.pattern).join(', ')}]`)
+		.replace('__COMPONENTS__', components)
+		.replace('__PAGES__', pages) +
+		footer;
+}
+
+function generate_server(
+	manifest_data: ManifestData,
+	path_to_routes: string,
+	cwd: string,
+	src: string,
+	dest: string,
+	dev: boolean
+) {
+	const template_file = path.resolve(__dirname, '../templates/server.js');
+	const template = fs.readFileSync(template_file, 'utf-8');
+
+	const imports = [].concat(
+		manifest_data.server_routes.map(route =>
+			`import * as __${route.name} from ${stringify(posixify(`${path_to_routes}/${route.file}`))};`),
+		manifest_data.components.map(component =>
+			`import __${component.name} from ${stringify(get_file(path_to_routes, component))};`),
+		`import root from ${stringify(get_file(path_to_routes, manifest_data.root))};`,
+		`import error from ${stringify(posixify(`${path_to_routes}/_error.html`))};`
+	);
+
+	let code = `
+		${imports.join('\n')}
+
+		const d = decodeURIComponent;
+
+		export const manifest = {
+			server_routes: [
+				${manifest_data.server_routes.map(route => `{
+					// ${route.file}
+					pattern: ${route.pattern},
+					handlers: __${route.name},
+					params: ${route.params.length > 0
+						? `match => ({ ${route.params.map((param, i) => `${param}: d(match[${i + 1}])`).join(', ')} })`
+						: `() => ({})`}
+				}`).join(',\n\n\t\t\t\t')}
+			],
+
+			pages: [
+				${manifest_data.pages.map(page => `{
+					// ${page.parts[page.parts.length - 1].component.file}
+					pattern: ${page.pattern},
+					parts: [
+						${page.parts.map(part => {
+							if (part === null) return 'null';
+
+							const props = [
+								`name: "${part.component.name}"`,
+								`file: ${stringify(part.component.file)}`,
+								`component: __${part.component.name}`
+							];
+
+							if (part.params.length > 0) {
+								const params = part.params.map((param, i) => `${param}: d(match[${i + 1}])`);
+								props.push(`params: match => ({ ${params.join(', ')} })`);
+							}
+
+							return `{ ${props.join(', ')} }`;
+						}).join(',\n\t\t\t\t\t\t')}
+					]
+				}`).join(',\n\n\t\t\t\t')}
+			],
+
+			root,
+
+			error
+		};`.replace(/^\t\t/gm, '').trim();
+
+	const build_dir = posixify(path.relative(cwd, dest));
+	const src_dir = posixify(path.relative(cwd, src));
+
+	return `// This file is generated by Sapper — do not edit it!\n` + template
+		.replace('__BUILD__DIR__', JSON.stringify(build_dir))
+		.replace('__SRC__DIR__', JSON.stringify(src_dir))
+		.replace('__DEV__', dev ? 'true' : 'false')
+		.replace(/const manifest = __MANIFEST__;/, code);
+}
+
+function get_file(path_to_routes: string, component: PageComponent) {
+	if (component.default) {
+		return `./_layout.html`;
+	}
+
+	return posixify(`${path_to_routes}/${component.file}`);
+}
--- a/src/core/read_template.ts
+++ b/src/core/read_template.ts
@@ -0,0 +1,16 @@
+import * as fs from 'fs';
+
+export default function read_template(dir: string) {
+	try {
+		return fs.readFileSync(`${dir}/template.html`, 'utf-8');
+	} catch (err) {
+		if (fs.existsSync(`app/template.html`)) {
+			throw new Error(`As of Sapper 0.21, the default folder structure has been changed:
+  app/    --> src/
+  routes/ --> src/routes/
+  assets/ --> static/`);
+		}
+
+		throw err;
+	}
+}
--- a/src/interfaces.ts
+++ b/src/interfaces.ts
@@ -0,0 +1,100 @@
+import * as child_process from 'child_process';
+import { CompileResult } from './core/create_compilers/interfaces';
+
+export type Route = {
+	id: string;
+	handlers: {
+		type: 'page' | 'route';
+		file: string;
+	}[];
+	pattern: RegExp;
+	test: (url: string) => boolean;
+	exec: (url: string) => Record<string, string>;
+	parts: string[];
+	params: string[];
+};
+
+export type Template = {
+	render: (data: Record<string, string>) => string;
+	stream: (req, res, data: Record<string, string | Promise<string>>) => void;
+};
+
+export type Store = {
+	get: () => any;
+};
+
+export type PageComponent = {
+	default?: boolean;
+	name: string;
+	file: string;
+};
+
+export type Page = {
+	pattern: RegExp;
+	parts: Array<{
+		component: PageComponent;
+		params: string[];
+	}>
+};
+
+export type ServerRoute = {
+	name: string;
+	pattern: RegExp;
+	file: string;
+	params: string[];
+};
+
+export type Dirs = {
+	dest: string,
+	src: string,
+	routes: string
+};
+
+export type ManifestData = {
+	root: PageComponent;
+	components: PageComponent[];
+	pages: Page[];
+	server_routes: ServerRoute[];
+};
+
+export type ReadyEvent = {
+	port: number;
+	process: child_process.ChildProcess;
+};
+
+export type ErrorEvent = {
+	type: string;
+	message: string;
+};
+
+export type FatalEvent = {
+	message: string;
+};
+
+export type InvalidEvent = {
+	changed: string[];
+	invalid: {
+		client: boolean;
+		server: boolean;
+		serviceworker: boolean;
+	}
+};
+
+export type BuildEvent = {
+	type: string;
+	errors: Array<{ file: string, message: string, duplicate: boolean }>;
+	warnings: Array<{ file: string, message: string, duplicate: boolean }>;
+	duration: number;
+	result: CompileResult;
+};
+
+export type FileEvent = {
+	file: string;
+	size: number;
+};
+
+export type FailureEvent = {
+
+};
+
+export type DoneEvent = {};
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -0,0 +1,119 @@
+import * as fs from 'fs';
+import * as path from 'path';
+
+export function left_pad(str: string, len: number) {
+	while (str.length < len) str = ` ${str}`;
+	return str;
+}
+
+export function repeat(str: string, i: number) {
+	let result = '';
+	while (i--) result += str;
+	return result;
+}
+
+export function format_milliseconds(ms: number) {
+	if (ms < 1000) return `${ms}ms`;
+	if (ms < 60000) return `${(ms / 1000).toFixed(1)}s`;
+
+	const minutes = ~~(ms / 60000);
+	const seconds = Math.round((ms % 60000) / 1000);
+	return `${minutes}m${seconds < 10 ? '0' : ''}${seconds}s`;
+}
+
+export function elapsed(start: number) {
+	return format_milliseconds(Date.now() - start);
+}
+
+export function walk(cwd: string, dir = cwd, files: string[] = []) {
+	fs.readdirSync(dir).forEach(file => {
+		const resolved = path.resolve(dir, file);
+		if (fs.statSync(resolved).isDirectory()) {
+			walk(cwd, resolved, files);
+		} else {
+			files.push(posixify(path.relative(cwd, resolved)));
+		}
+	});
+
+	return files;
+}
+
+export function posixify(str: string) {
+	return str.replace(/\\/g, '/');
+}
+
+const previous_contents = new Map();
+
+export function write_if_changed(file: string, code: string) {
+	if (code !== previous_contents.get(file)) {
+		previous_contents.set(file, code);
+		fs.writeFileSync(file, code);
+		fudge_mtime(file);
+	}
+}
+
+export function stringify(string: string, includeQuotes: boolean = true) {
+	const quoted = JSON.stringify(string);
+	return includeQuotes ? quoted : quoted.slice(1, -1);
+}
+
+export function fudge_mtime(file: string) {
+	// need to fudge the mtime so that webpack doesn't go doolally
+	const { atime, mtime } = fs.statSync(file);
+	fs.utimesSync(
+		file,
+		new Date(atime.getTime() - 999999),
+		new Date(mtime.getTime() - 999999)
+	);
+}
+
+export const reserved_words = new Set([
+	'arguments',
+	'await',
+	'break',
+	'case',
+	'catch',
+	'class',
+	'const',
+	'continue',
+	'debugger',
+	'default',
+	'delete',
+	'do',
+	'else',
+	'enum',
+	'eval',
+	'export',
+	'extends',
+	'false',
+	'finally',
+	'for',
+	'function',
+	'if',
+	'implements',
+	'import',
+	'in',
+	'instanceof',
+	'interface',
+	'let',
+	'new',
+	'null',
+	'package',
+	'private',
+	'protected',
+	'public',
+	'return',
+	'static',
+	'super',
+	'switch',
+	'this',
+	'throw',
+	'true',
+	'try',
+	'typeof',
+	'var',
+	'void',
+	'while',
+	'with',
+	'yield',
+]);
--- a/templates/src/client/app.ts
+++ b/templates/src/client/app.ts
@@ -0,0 +1,389 @@
+import RootComponent from '__ROOT__';
+import ErrorComponent from '__ERROR__';
+import {
+	Target,
+	ScrollPosition,
+	Component,
+	Redirect,
+	ComponentLoader,
+	ComponentConstructor,
+	RootProps,
+	Page
+} from './types';
+import goto from './goto';
+
+const ignore = __IGNORE__;
+export const components: ComponentLoader[] = __COMPONENTS__;
+export const pages: Page[] = __PAGES__;
+
+let ready = false;
+let root_component: Component;
+let segments: string[] = [];
+let current_token: {};
+let root_preload: Promise<any>;
+let root_data: any;
+
+const root_props: RootProps = {
+	path: null,
+	params: null,
+	query: null,
+	child: {
+		segment: null,
+		component: null,
+		props: {}
+	}
+};
+
+export let prefetching: {
+	href: string;
+	promise: Promise<{ redirect?: Redirect, data?: any, nullable_depth?: number }>;
+} = null;
+export function set_prefetching(href, promise) {
+	prefetching = { href, promise };
+}
+
+export let store;
+export function set_store(fn) {
+	store = fn(initial_data.store);
+}
+
+export let target: Node;
+export function set_target(element) {
+	target = element;
+}
+
+export let uid = 1;
+export function set_uid(n) {
+	uid = n;
+}
+
+export let cid: number;
+export function set_cid(n) {
+	cid = n;
+}
+
+export const initial_data = typeof __SAPPER__ !== 'undefined' && __SAPPER__;
+
+const _history = typeof history !== 'undefined' ? history : {
+	pushState: (state: any, title: string, href: string) => {},
+	replaceState: (state: any, title: string, href: string) => {},
+	scrollRestoration: ''
+};
+export { _history as history };
+
+export const scroll_history: Record<string, ScrollPosition> = {};
+
+export function select_route(url: URL): Target {
+	if (url.origin !== location.origin) return null;
+	if (!url.pathname.startsWith(initial_data.baseUrl)) return null;
+
+	const path = url.pathname.slice(initial_data.baseUrl.length);
+
+	// avoid accidental clashes between server routes and pages
+	if (ignore.some(pattern => pattern.test(path))) return;
+
+	for (let i = 0; i < pages.length; i += 1) {
+		const page = pages[i];
+
+		const match = page.pattern.exec(path);
+		if (match) {
+			const query: Record<string, string | string[]> = Object.create(null);
+			if (url.search.length > 0) {
+				url.search.slice(1).split('&').forEach(searchParam => {
+					let [, key, value] = /([^=]*)(?:=(.*))?/.exec(decodeURIComponent(searchParam));
+					value = (value || '').replace(/\+/g, ' ');
+					if (typeof query[key] === 'string') query[key] = [<string>query[key]];
+					if (typeof query[key] === 'object') query[key].push(value);
+					else query[key] = value;
+				});
+			}
+			return { url, path, page, match, query };
+		}
+	}
+}
+
+export function scroll_state() {
+	return {
+		x: pageXOffset,
+		y: pageYOffset
+	};
+}
+
+export function navigate(target: Target, id: number, noscroll?: boolean, hash?: string): Promise<any> {
+	let scroll: ScrollPosition;
+	if (id) {
+		// popstate or initial navigation
+		cid = id;
+	} else {
+		const current_scroll = scroll_state();
+
+		// clicked on a link. preserve scroll state
+		scroll_history[cid] = current_scroll;
+
+		id = cid = ++uid;
+		scroll_history[cid] = noscroll ? current_scroll : { x: 0, y: 0 };
+	}
+
+	cid = id;
+
+	if (root_component) {
+		root_component.set({ preloading: true });
+	}
+	const loaded = prefetching && prefetching.href === target.url.href ?
+		prefetching.promise :
+		prepare_page(target);
+
+	prefetching = null;
+
+	const token = current_token = {};
+
+	return loaded.then(({ redirect, data, nullable_depth }) => {
+		if (redirect) {
+			return goto(redirect.location, { replaceState: true });
+		}
+		render(data, nullable_depth, scroll_history[id], noscroll, hash, token);
+		if (document.activeElement) document.activeElement.blur();
+	});
+}
+
+function render(data: any, nullable_depth: number, scroll: ScrollPosition, noscroll: boolean, hash: string, token: {}) {
+	if (current_token !== token) return;
+
+	if (root_component) {
+		// first, clear out highest-level root component
+		let level = data.child;
+		for (let i = 0; i < nullable_depth; i += 1) {
+			if (i === nullable_depth) break;
+			level = level.props.child;
+		}
+
+		const { component } = level;
+		level.component = null;
+		root_component.set({ child: data.child });
+
+		// then render new stuff
+		level.component = component;
+		root_component.set(data);
+	} else {
+		// first load — remove SSR'd <head> contents
+		const start = document.querySelector('#sapper-head-start');
+		const end = document.querySelector('#sapper-head-end');
+
+		if (start && end) {
+			while (start.nextSibling !== end) detach(start.nextSibling);
+			detach(start);
+			detach(end);
+		}
+
+		Object.assign(data, root_data);
+
+		root_component = new RootComponent({
+			target,
+			data,
+			store,
+			hydrate: true
+		});
+	}
+
+	if (!noscroll) {
+		if (hash) {
+			// scroll is an element id (from a hash), we need to compute y.
+			const deep_linked = document.querySelector(hash);
+			if (deep_linked) {
+				scroll = {
+					x: 0,
+					y: deep_linked.getBoundingClientRect().top
+				};
+			}
+		}
+
+		scroll_history[cid] = scroll;
+		if (scroll) scrollTo(scroll.x, scroll.y);
+	}
+
+	Object.assign(root_props, data);
+	ready = true;
+}
+
+export function prepare_page(target: Target): Promise<{
+	redirect?: Redirect;
+	data?: any;
+	nullable_depth?: number;
+}> {
+	const { page, path, query } = target;
+	const new_segments = path.split('/').filter(Boolean);
+	let changed_from = 0;
+
+	while (
+		segments[changed_from] &&
+		new_segments[changed_from] &&
+		segments[changed_from] === new_segments[changed_from]
+	) changed_from += 1;
+
+	let redirect: Redirect = null;
+	let error: { statusCode: number, message: Error | string } = null;
+
+	const preload_context = {
+		store,
+		fetch: (url: string, opts?: any) => fetch(url, opts),
+		redirect: (statusCode: number, location: string) => {
+			if (redirect && (redirect.statusCode !== statusCode || redirect.location !== location)) {
+				throw new Error(`Conflicting redirects`);
+			}
+			redirect = { statusCode, location };
+		},
+		error: (statusCode: number, message: Error | string) => {
+			error = { statusCode, message };
+		}
+	};
+
+	if (!root_preload) {
+		root_preload = RootComponent.preload
+			? initial_data.preloaded[0] || RootComponent.preload.call(preload_context, {
+				path,
+				query,
+				params: {}
+			})
+			: {};
+	}
+
+	return Promise.all(page.parts.map((part, i) => {
+		if (i < changed_from) return null;
+		if (!part) return null;
+
+		return load_component(components[part.i]).then(Component => {
+			const req = {
+				path,
+				query,
+				params: part.params ? part.params(target.match) : {}
+			};
+
+			let preloaded;
+			if (ready || !initial_data.preloaded[i + 1]) {
+				preloaded = Component.preload
+					? Component.preload.call(preload_context, req)
+					: {};
+			} else {
+				preloaded = initial_data.preloaded[i + 1];
+			}
+
+			return Promise.resolve(preloaded).then(preloaded => {
+				return { Component, preloaded };
+			});
+		});
+	})).catch(err => {
+		error = { statusCode: 500, message: err };
+		return [];
+	}).then(results => {
+		if (root_data) {
+			return results;
+		} else {
+			return Promise.resolve(root_preload).then(value => {
+				root_data = value;
+				return results;
+			});
+		}
+	}).then(results => {
+		if (redirect) {
+			return { redirect };
+		}
+
+		segments = new_segments;
+
+		const get_params = page.parts[page.parts.length - 1].params || (() => ({}));
+		const params = get_params(target.match);
+
+		if (error) {
+			const props = {
+				path,
+				query,
+				params,
+				error: typeof error.message === 'string' ? new Error(error.message) : error.message,
+				status: error.statusCode
+			};
+
+			return {
+				data: Object.assign({}, props, {
+					preloading: false,
+					child: {
+						component: ErrorComponent,
+						props
+					}
+				})
+			};
+		}
+
+		const props = { path, query, error: null, status: null };
+		const data = {
+			path,
+			preloading: false,
+			child: Object.assign({}, root_props.child, {
+				segment: segments[0]
+			})
+		};
+		if (changed(query, root_props.query)) data.query = query;
+		if (changed(params, root_props.params)) data.params = params;
+
+		let level = data.child;
+		let nullable_depth = 0;
+
+		for (let i = 0; i < page.parts.length; i += 1) {
+			const part = page.parts[i];
+			if (!part) continue;
+
+			const get_params = part.params || (() => ({}));
+
+			if (i < changed_from) {
+				level.props.path = path;
+				level.props.query = query;
+				level.props.child = Object.assign({}, level.props.child);
+
+				nullable_depth += 1;
+			} else {
+				level.component = results[i].Component;
+				level.props = Object.assign({}, level.props, props, {
+					params: get_params(target.match),
+				}, results[i].preloaded);
+
+				level.props.child = {};
+			}
+
+			level = level.props.child;
+			level.segment = segments[i + 1];
+		}
+
+		return { data, nullable_depth };
+	});
+}
+
+function load_css(chunk: string) {
+	const href = `client/${chunk}`;
+	if (document.querySelector(`link[href="${href}"]`)) return;
+
+	return new Promise((fulfil, reject) => {
+		const link = document.createElement('link');
+		link.rel = 'stylesheet';
+		link.href = href;
+
+		link.onload = () => fulfil();
+		link.onerror = reject;
+
+		document.head.appendChild(link);
+	});
+}
+
+export function load_component(component: ComponentLoader): Promise<ComponentConstructor> {
+	// TODO this is temporary — once placeholders are
+	// always rewritten, scratch the ternary
+	const promises: Array<Promise<any>> = (typeof component.css === 'string' ? [] : component.css.map(load_css));
+	promises.unshift(component.js());
+	return Promise.all(promises).then(values => values[0].default);
+}
+
+function detach(node: Node) {
+	node.parentNode.removeChild(node);
+}
+
+function changed(a: Record<string, string | true>, b: Record<string, string | true>) {
+	return JSON.stringify(a) !== JSON.stringify(b);
+}
--- a/templates/src/client/goto/index.ts
+++ b/templates/src/client/goto/index.ts
@@ -0,0 +1,13 @@
+import { history, select_route, navigate, cid } from '../app';
+
+export default function goto(href: string, opts = { replaceState: false }) {
+	const target = select_route(new URL(href, document.baseURI));
+
+	if (target) {
+		history[opts.replaceState ? 'replaceState' : 'pushState']({ id: cid }, '', href);
+		return navigate(target, null).then(() => {});
+	}
+
+	location.href = href;
+	return new Promise(f => {}); // never resolves
+}
--- a/templates/src/client/index.ts
+++ b/templates/src/client/index.ts
@@ -0,0 +1,4 @@
+export { default as start } from './start/index';
+export { default as goto } from './goto/index';
+export { default as prefetch } from './prefetch/index';
+export { default as prefetchRoutes } from './prefetchRoutes/index';
--- a/templates/src/client/prefetch/index.ts
+++ b/templates/src/client/prefetch/index.ts
@@ -0,0 +1,14 @@
+import { select_route, prefetching, set_prefetching, prepare_page } from '../app';
+import { Target } from '../types';
+
+export default function prefetch(href: string) {
+	const target: Target = select_route(new URL(href, document.baseURI));
+
+	if (target) {
+		if (!prefetching || href !== prefetching.href) {
+			set_prefetching(href, prepare_page(target));
+		}
+
+		return prefetching.promise;
+	}
+}
--- a/templates/src/client/prefetchRoutes/index.ts
+++ b/templates/src/client/prefetchRoutes/index.ts
@@ -0,0 +1,12 @@
+import { components, pages, load_component } from "../app";
+
+export default function prefetchRoutes(pathnames: string[]) {
+	return pages
+		.filter(route => {
+			if (!pathnames) return true;
+			return pathnames.some(pathname => route.pattern.test(pathname));
+		})
+		.reduce((promise: Promise<any>, route) => promise.then(() => {
+			return Promise.all(route.parts.map(part => part && load_component(components[part.i])));
+		}), Promise.resolve());
+}
--- a/templates/src/client/start/index.ts
+++ b/templates/src/client/start/index.ts
@@ -0,0 +1,134 @@
+import {
+	cid,
+	history,
+	initial_data,
+	navigate,
+	scroll_history,
+	scroll_state,
+	select_route,
+	set_store,
+	set_target,
+	uid,
+	set_uid,
+	set_cid
+} from '../app';
+import prefetch from '../prefetch/index';
+import { Store, ScrollPosition } from '../types';
+
+export default function start(opts: {
+	target: Node,
+	store?: (data: any) => Store
+}) {
+	if ('scrollRestoration' in history) {
+		history.scrollRestoration = 'manual';
+	}
+
+	set_target(opts.target);
+	if (opts.store) set_store(opts.store);
+
+	addEventListener('click', handle_click);
+	addEventListener('popstate', handle_popstate);
+
+	// prefetch
+	addEventListener('touchstart', trigger_prefetch);
+	addEventListener('mousemove', handle_mousemove);
+
+	return Promise.resolve().then(() => {
+		const { hash, href } = location;
+
+		history.replaceState({ id: uid }, '', href);
+
+		if (!initial_data.error) {
+			const target = select_route(new URL(location.href));
+			if (target) return navigate(target, uid, false, hash);
+		}
+	});
+}
+
+let mousemove_timeout: NodeJS.Timer;
+
+function handle_mousemove(event: MouseEvent) {
+	clearTimeout(mousemove_timeout);
+	mousemove_timeout = setTimeout(() => {
+		trigger_prefetch(event);
+	}, 20);
+}
+
+function trigger_prefetch(event: MouseEvent | TouchEvent) {
+	const a: HTMLAnchorElement = <HTMLAnchorElement>find_anchor(<Node>event.target);
+	if (!a || a.rel !== 'prefetch') return;
+
+	prefetch(a.href);
+}
+
+function handle_click(event: MouseEvent) {
+	// Adapted from https://github.com/visionmedia/page.js
+	// MIT license https://github.com/visionmedia/page.js#license
+	if (which(event) !== 1) return;
+	if (event.metaKey || event.ctrlKey || event.shiftKey) return;
+	if (event.defaultPrevented) return;
+
+	const a: HTMLAnchorElement | SVGAElement = <HTMLAnchorElement | SVGAElement>find_anchor(<Node>event.target);
+	if (!a) return;
+
+	if (!a.href) return;
+
+	// check if link is inside an svg
+	// in this case, both href and target are always inside an object
+	const svg = typeof a.href === 'object' && a.href.constructor.name === 'SVGAnimatedString';
+	const href = String(svg ? (<SVGAElement>a).href.baseVal : a.href);
+
+	if (href === location.href) {
+		if (!location.hash) event.preventDefault();
+		return;
+	}
+
+	// Ignore if tag has
+	// 1. 'download' attribute
+	// 2. rel='external' attribute
+	if (a.hasAttribute('download') || a.getAttribute('rel') === 'external') return;
+
+	// Ignore if <a> has a target
+	if (svg ? (<SVGAElement>a).target.baseVal : a.target) return;
+
+	const url = new URL(href);
+
+	// Don't handle hash changes
+	if (url.pathname === location.pathname && url.search === location.search) return;
+
+	const target = select_route(url);
+	if (target) {
+		const noscroll = a.hasAttribute('sapper-noscroll');
+		navigate(target, null, noscroll, url.hash);
+		event.preventDefault();
+		history.pushState({ id: cid }, '', url.href);
+	}
+}
+
+function which(event: MouseEvent) {
+	return event.which === null ? event.button : event.which;
+}
+
+function find_anchor(node: Node) {
+	while (node && node.nodeName.toUpperCase() !== 'A') node = node.parentNode; // SVG <a> elements have a lowercase name
+	return node;
+}
+
+function handle_popstate(event: PopStateEvent) {
+	scroll_history[cid] = scroll_state();
+
+	if (event.state) {
+		const url = new URL(location.href);
+		const target = select_route(url);
+		if (target) {
+			navigate(target, event.state.id);
+		} else {
+			location.href = location.href;
+		}
+	} else {
+		// hashchange
+		set_uid(uid + 1);
+		set_cid(uid);
+		history.replaceState({ id: cid }, '', location.href);
+	}
+}
--- a/templates/src/client/types.ts
+++ b/templates/src/client/types.ts
@@ -0,0 +1,68 @@
+export type Params = Record<string, string>;
+export type Query = Record<string, string | true>;
+export type RouteData = { params: Params, query: Query, path: string };
+
+type Child = {
+	segment?: string;
+	props?: any;
+	component?: Component;
+};
+
+export type RootProps = {
+	path: string;
+	params: Record<string, string>;
+	query: Record<string, string>;
+	child: Child;
+};
+
+export interface ComponentConstructor {
+	new (options: { target: Node, data: any, store: Store, hydrate: boolean }): Component;
+	preload: (props: { params: Params, query: Query }) => Promise<any>;
+};
+
+export interface Component {
+	set: (data: any) => void;
+	destroy: () => void;
+}
+
+export type ComponentLoader = {
+	js: () => Promise<{ default: ComponentConstructor }>,
+	css: string[]
+};
+
+export type Page = {
+	pattern: RegExp;
+	parts: Array<{
+		i: number;
+		params?: (match: RegExpExecArray) => Record<string, string>;
+	}>;
+};
+
+export type Manifest = {
+	ignore: RegExp[];
+	root: ComponentConstructor;
+	error: () => Promise<{ default: ComponentConstructor }>;
+	pages: Page[]
+};
+
+export type ScrollPosition = {
+	x: number;
+	y: number;
+};
+
+export type Target = {
+	url: URL;
+	path: string;
+	page: Page;
+	match: RegExpExecArray;
+	query: Record<string, string | string[]>;
+};
+
+export type Redirect = {
+	statusCode: number;
+	location: string;
+};
+
+export type Store = {
+	get: () => any;
+}
--- a/templates/src/server/index.ts
+++ b/templates/src/server/index.ts
@@ -0,0 +1 @@
+export { default as middleware } from './middleware/index';
--- a/templates/src/server/middleware/get_page_handler.ts
+++ b/templates/src/server/middleware/get_page_handler.ts
@@ -0,0 +1,359 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import cookie from 'cookie';
+import devalue from 'devalue';
+import fetch from 'node-fetch';
+import { URL, resolve } from 'url';
+import { build_dir, dev, src_dir, IGNORE } from '../placeholders';
+import { Manifest, Page, Props, Req, Res, Store } from './types';
+
+export function get_page_handler(
+	manifest: Manifest,
+	store_getter: (req: Req, res: Res) => Store
+) {
+	const get_build_info = dev
+		? () => JSON.parse(fs.readFileSync(path.join(build_dir, 'build.json'), 'utf-8'))
+		: (assets => () => assets)(JSON.parse(fs.readFileSync(path.join(build_dir, 'build.json'), 'utf-8')));
+
+	const template = dev
+		? () => read_template(src_dir)
+		: (str => () => str)(read_template(build_dir));
+
+	const has_service_worker = fs.existsSync(path.join(build_dir, 'service-worker.js'));
+
+	const { server_routes, pages } = manifest;
+	const error_route = manifest.error;
+
+	function handle_error(req: Req, res: Res, statusCode: number, error: Error | string) {
+		handle_page({
+			pattern: null,
+			parts: [
+				{ name: null, component: error_route }
+			]
+		}, req, res, statusCode, error || new Error('Unknown error in preload function'));
+	}
+
+	async function handle_page(page: Page, req: Req, res: Res, status = 200, error: Error | string = null) {
+		const isSWIndexHtml = req.path === '/service-worker-index.html';
+		const build_info: {
+			bundler: 'rollup' | 'webpack',
+			shimport: string | null,
+			assets: Record<string, string | string[]>,
+			legacy_assets?: Record<string, string>
+		 } = get_build_info();
+
+		res.setHeader('Content-Type', 'text/html');
+		res.setHeader('Cache-Control', dev ? 'no-cache' : 'max-age=600');
+
+		// preload main.js and current route
+		// TODO detect other stuff we can preload? images, CSS, fonts?
+		let preloaded_chunks = Array.isArray(build_info.assets.main) ? build_info.assets.main : [build_info.assets.main];
+		if (!error && !isSWIndexHtml) {
+			page.parts.forEach(part => {
+				if (!part) return;
+
+				// using concat because it could be a string or an array. thanks webpack!
+				preloaded_chunks = preloaded_chunks.concat(build_info.assets[part.name]);
+			});
+		}
+
+		if (build_info.bundler === 'rollup') {
+			// TODO add dependencies and CSS
+			const link = preloaded_chunks
+				.filter(file => file && !file.match(/\.map$/))
+				.map(file => `<${req.baseUrl}/client/${file}>;rel="modulepreload"`)
+				.join(', ');
+
+			res.setHeader('Link', link);
+		} else {
+			const link = preloaded_chunks
+				.filter(file => file && !file.match(/\.map$/))
+				.map((file) => {
+					const as = /\.css$/.test(file) ? 'style' : 'script';
+					return `<${req.baseUrl}/client/${file}>;rel="preload";as="${as}"`;
+				})
+				.join(', ');
+
+			res.setHeader('Link', link);
+		}
+
+		const store = store_getter ? store_getter(req, res) : null;
+
+		let redirect: { statusCode: number, location: string };
+		let preload_error: { statusCode: number, message: Error | string };
+
+		const preload_context = {
+			redirect: (statusCode: number, location: string) => {
+				if (redirect && (redirect.statusCode !== statusCode || redirect.location !== location)) {
+					throw new Error(`Conflicting redirects`);
+				}
+				location = location.replace(/^\//g, ''); // leading slash (only)
+				redirect = { statusCode, location };
+			},
+			error: (statusCode: number, message: Error | string) => {
+				preload_error = { statusCode, message };
+			},
+			fetch: (url: string, opts?: any) => {
+				const parsed = new URL(url, `http://127.0.0.1:${process.env.PORT}${req.baseUrl ? req.baseUrl + '/' :''}`);
+
+				if (opts) {
+					opts = Object.assign({}, opts);
+
+					const include_cookies = (
+						opts.credentials === 'include' ||
+						opts.credentials === 'same-origin' && parsed.origin === `http://127.0.0.1:${process.env.PORT}`
+					);
+
+					if (include_cookies) {
+						if (!opts.headers) opts.headers = {};
+
+						const cookies = Object.assign(
+							{},
+							cookie.parse(req.headers.cookie || ''),
+							cookie.parse(opts.headers.cookie || '')
+						);
+
+						const set_cookie = res.getHeader('Set-Cookie');
+						(Array.isArray(set_cookie) ? set_cookie : [set_cookie]).forEach(str => {
+							const match = /([^=]+)=([^;]+)/.exec(<string>str);
+							if (match) cookies[match[1]] = match[2];
+						});
+
+						const str = Object.keys(cookies)
+							.map(key => `${key}=${cookies[key]}`)
+							.join('; ');
+
+						opts.headers.cookie = str;
+					}
+				}
+
+				return fetch(parsed.href, opts);
+			},
+			store
+		};
+
+		let preloaded;
+		let match;
+
+		try {
+			const root_preloaded = manifest.root.preload
+				? manifest.root.preload.call(preload_context, {
+					path: req.path,
+					query: req.query,
+					params: {}
+				})
+				: {};
+
+			match = error ? null : page.pattern.exec(req.path);
+
+			let toPreload = [root_preloaded];
+			if (!isSWIndexHtml) {
+				toPreload = toPreload.concat(page.parts.map(part => {
+					if (!part) return null;
+
+					return part.component.preload
+						? part.component.preload.call(preload_context, {
+							path: req.path,
+							query: req.query,
+							params: part.params ? part.params(match) : {}
+						})
+						: {};
+				}))
+			}
+
+			preloaded = await Promise.all(toPreload);
+		} catch (err) {
+			preload_error = { statusCode: 500, message: err };
+			preloaded = []; // appease TypeScript
+		}
+
+		try {
+			if (redirect) {
+				const location = resolve(req.baseUrl || '/', redirect.location);
+
+				res.statusCode = redirect.statusCode;
+				res.setHeader('Location', location);
+				res.end();
+
+				return;
+			}
+
+			if (preload_error) {
+				handle_error(req, res, preload_error.statusCode, preload_error.message);
+				return;
+			}
+
+			const serialized = {
+				preloaded: `[${preloaded.map(data => try_serialize(data)).join(',')}]`,
+				store: store && try_serialize(store.get())
+			};
+
+			const segments = req.path.split('/').filter(Boolean);
+
+			const props: Props = {
+				path: req.path,
+				query: req.query,
+				params: {},
+				child: null
+			};
+
+			if (error) {
+				props.error = error instanceof Error ? error : { message: error };
+				props.status = status;
+			}
+
+			const data = Object.assign({}, props, preloaded[0], {
+				params: {},
+				child: {
+					segment: segments[0]
+				}
+			});
+
+			let level = data.child;
+			if (isSWIndexHtml) {
+				level.props = Object.assign({}, props, {
+					params: {}
+				})
+			} else {
+				for (let i = 0; i < page.parts.length; i += 1) {
+					const part = page.parts[i];
+					if (!part) continue;
+
+					const get_params = part.params || (() => ({}));
+
+					Object.assign(level, {
+						component: part.component,
+						props: Object.assign({}, props, {
+							params: get_params(match)
+						}, preloaded[i + 1])
+					});
+
+					level.props.child = <Props["child"]>{
+						segment: segments[i + 1]
+					};
+					level = level.props.child;
+				}
+			}
+
+			const { html, head, css } = manifest.root.render(data, {
+				store
+			});
+
+			let script = `__SAPPER__={${[
+				error && `error:1`,
+				`baseUrl:"${req.baseUrl}"`,
+				serialized.preloaded && `preloaded:${serialized.preloaded}`,
+				serialized.store && `store:${serialized.store}`
+			].filter(Boolean).join(',')}};`;
+
+			if (has_service_worker) {
+				script += `if('serviceWorker' in navigator)navigator.serviceWorker.register('${req.baseUrl}/service-worker.js');`;
+			}
+
+			const file = [].concat(build_info.assets.main).filter(file => file && /\.js$/.test(file))[0];
+			const main = `${req.baseUrl}/client/${file}`;
+
+			if (build_info.bundler === 'rollup') {
+				if (build_info.legacy_assets) {
+					const legacy_main = `${req.baseUrl}/client/legacy/${build_info.legacy_assets.main}`;
+					script += `(function(){try{eval("async function x(){}");var main="${main}"}catch(e){main="${legacy_main}"};var s=document.createElement("script");try{new Function("if(0)import('')")();s.src=main;s.type="module";s.crossOrigin="use-credentials";}catch(e){s.src="${req.baseUrl}/client/shimport@${build_info.shimport}.js";s.setAttribute("data-main",main);}document.head.appendChild(s);}());`;
+				} else {
+					script += `var s=document.createElement("script");try{new Function("if(0)import('')")();s.src="${main}";s.type="module";s.crossOrigin="use-credentials";}catch(e){s.src="${req.baseUrl}/client/shimport@${build_info.shimport}.js";s.setAttribute("data-main","${main}")}document.head.appendChild(s)`;
+				}
+			} else {
+				script += `</script><script src="${main}">`;
+			}
+
+			let styles: string;
+
+			// TODO make this consistent across apps
+			// TODO embed build_info in placeholder.ts
+			if (build_info.css && build_info.css.main) {
+				const css_chunks = new Set();
+				if (build_info.css.main) css_chunks.add(build_info.css.main);
+				page.parts.forEach(part => {
+					if (!part) return;
+					const css_chunks_for_part = build_info.css.chunks[part.file];
+
+					if (css_chunks_for_part) {
+						css_chunks_for_part.forEach(file => {
+							css_chunks.add(file);
+						});
+					}
+				});
+
+				styles = Array.from(css_chunks)
+					.map(href => `<link rel="stylesheet" href="client/${href}">`)
+					.join('')
+			} else {
+				styles = (css && css.code ? `<style>${css.code}</style>` : '');
+			}
+
+			// users can set a CSP nonce using res.locals.nonce
+			const nonce_attr = (res.locals && res.locals.nonce) ? ` nonce="${res.locals.nonce}"` : '';
+
+			const body = template()
+				.replace('%sapper.base%', () => `<base href="${req.baseUrl}/">`)
+				.replace('%sapper.scripts%', () => `<script${nonce_attr}>${script}</script>`)
+				.replace('%sapper.html%', () => html)
+				.replace('%sapper.head%', () => `<noscript id='sapper-head-start'></noscript>${head}<noscript id='sapper-head-end'></noscript>`)
+				.replace('%sapper.styles%', () => styles);
+
+			res.statusCode = status;
+			res.end(body);
+		} catch(err) {
+			if (error) {
+				// we encountered an error while rendering the error page — oops
+				res.statusCode = 500;
+				res.end(`<pre>${escape_html(err.message)}</pre>`);
+			} else {
+				handle_error(req, res, 500, err);
+			}
+		}
+	}
+
+	return function find_route(req: Req, res: Res, next: () => void) {
+		if (req[IGNORE]) return next();
+
+		if (req.path === '/service-worker-index.html') {
+			const homePage = pages.find(page => page.pattern.test('/'));
+			handle_page(homePage, req, res);
+			return;
+		}
+
+		if (!server_routes.some(route => route.pattern.test(req.path))) {
+			for (const page of pages) {
+				if (page.pattern.test(req.path)) {
+					handle_page(page, req, res);
+					return;
+				}
+			}
+		}
+
+		handle_error(req, res, 404, 'Not found');
+	};
+}
+
+function read_template(dir = build_dir) {
+	return fs.readFileSync(`${dir}/template.html`, 'utf-8');
+}
+
+function try_serialize(data: any) {
+	try {
+		return devalue(data);
+	} catch (err) {
+		return null;
+	}
+}
+
+function escape_html(html: string) {
+	const chars: Record<string, string> = {
+		'"' : 'quot',
+		"'": '#39',
+		'&': 'amp',
+		'<' : 'lt',
+		'>' : 'gt'
+	};
+
+	return html.replace(/["'&<>]/g, c => `&${chars[c]};`);
+}
--- a/templates/src/server/middleware/get_server_route_handler.ts
+++ b/templates/src/server/middleware/get_server_route_handler.ts
@@ -0,0 +1,78 @@
+import { IGNORE } from '../placeholders';
+import { Req, Res, ServerRoute } from './types';
+
+export function get_server_route_handler(routes: ServerRoute[]) {
+	async function handle_route(route: ServerRoute, req: Req, res: Res, next: () => void) {
+		req.params = route.params(route.pattern.exec(req.path));
+
+		const method = req.method.toLowerCase();
+		// 'delete' cannot be exported from a module because it is a keyword,
+		// so check for 'del' instead
+		const method_export = method === 'delete' ? 'del' : method;
+		const handle_method = route.handlers[method_export];
+		if (handle_method) {
+			if (process.env.SAPPER_EXPORT) {
+				const { write, end, setHeader } = res;
+				const chunks: any[] = [];
+				const headers: Record<string, string> = {};
+
+				// intercept data so that it can be exported
+				res.write = function(chunk: any) {
+					chunks.push(Buffer.from(chunk));
+					write.apply(res, arguments);
+				};
+
+				res.setHeader = function(name: string, value: string) {
+					headers[name.toLowerCase()] = value;
+					setHeader.apply(res, arguments);
+				};
+
+				res.end = function(chunk?: any) {
+					if (chunk) chunks.push(Buffer.from(chunk));
+					end.apply(res, arguments);
+
+					process.send({
+						__sapper__: true,
+						event: 'file',
+						url: req.url,
+						method: req.method,
+						status: res.statusCode,
+						type: headers['content-type'],
+						body: Buffer.concat(chunks).toString()
+					});
+				};
+			}
+
+			const handle_next = (err?: Error) => {
+				if (err) {
+					res.statusCode = 500;
+					res.end(err.message);
+				} else {
+					process.nextTick(next);
+				}
+			};
+
+			try {
+				await handle_method(req, res, handle_next);
+			} catch (err) {
+				handle_next(err);
+			}
+		} else {
+			// no matching handler for method
+			process.nextTick(next);
+		}
+	}
+
+	return function find_route(req: Req, res: Res, next: () => void) {
+		if (req[IGNORE]) return next();
+
+		for (const route of routes) {
+			if (route.pattern.test(req.path)) {
+				handle_route(route, req, res, next);
+				return;
+			}
+		}
+
+		next();
+	};
+}
--- a/templates/src/server/middleware/index.ts
+++ b/templates/src/server/middleware/index.ts
@@ -0,0 +1,143 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import { build_dir, dev, manifest, IGNORE } from '../placeholders';
+import { Handler, Req, Res, Store } from './types';
+import { get_server_route_handler } from './get_server_route_handler';
+import { get_page_handler } from './get_page_handler';
+import { lookup } from './mime';
+
+export default function middleware(opts: {
+	store?: (req: Req, res: Res) => Store,
+	ignore?: any
+} = {}) {
+	const { store, ignore } = opts;
+
+	let emitted_basepath = false;
+
+	return compose_handlers([
+		ignore && ((req: Req, res: Res, next: () => void) => {
+			req[IGNORE] = should_ignore(req.path, ignore);
+			next();
+		}),
+
+		(req: Req, res: Res, next: () => void) => {
+			if (req[IGNORE]) return next();
+
+			if (req.baseUrl === undefined) {
+				let { originalUrl } = req;
+				if (req.url === '/' && originalUrl[originalUrl.length - 1] !== '/') {
+					originalUrl += '/';
+				}
+
+				req.baseUrl = originalUrl
+					? originalUrl.slice(0, -req.url.length)
+					: '';
+			}
+
+			if (!emitted_basepath && process.send) {
+				process.send({
+					__sapper__: true,
+					event: 'basepath',
+					basepath: req.baseUrl
+				});
+
+				emitted_basepath = true;
+			}
+
+			if (req.path === undefined) {
+				req.path = req.url.replace(/\?.*/, '');
+			}
+
+			next();
+		},
+
+		fs.existsSync(path.join(build_dir, 'index.html')) && serve({
+			pathname: '/index.html',
+			cache_control: dev ? 'no-cache' : 'max-age=600'
+		}),
+
+		fs.existsSync(path.join(build_dir, 'service-worker.js')) && serve({
+			pathname: '/service-worker.js',
+			cache_control: 'no-cache, no-store, must-revalidate'
+		}),
+
+		fs.existsSync(path.join(build_dir, 'service-worker.js.map')) && serve({
+			pathname: '/service-worker.js.map',
+			cache_control: 'no-cache, no-store, must-revalidate'
+		}),
+
+		serve({
+			prefix: '/client/',
+			cache_control: dev ? 'no-cache' : 'max-age=31536000, immutable'
+		}),
+
+		get_server_route_handler(manifest.server_routes),
+
+		get_page_handler(manifest, store)
+	].filter(Boolean));
+}
+
+export function compose_handlers(handlers: Handler[]) {
+	return (req: Req, res: Res, next: () => void) => {
+		let i = 0;
+		function go() {
+			const handler = handlers[i];
+
+			if (handler) {
+				handler(req, res, () => {
+					i += 1;
+					go();
+				});
+			} else {
+				next();
+			}
+		}
+
+		go();
+	};
+}
+
+export function should_ignore(uri: string, val: any) {
+	if (Array.isArray(val)) return val.some(x => should_ignore(uri, x));
+	if (val instanceof RegExp) return val.test(uri);
+	if (typeof val === 'function') return val(uri);
+	return uri.startsWith(val.charCodeAt(0) === 47 ? val : `/${val}`);
+}
+
+export function serve({ prefix, pathname, cache_control }: {
+	prefix?: string,
+	pathname?: string,
+	cache_control: string
+}) {
+	const filter = pathname
+		? (req: Req) => req.path === pathname
+		: (req: Req) => req.path.startsWith(prefix);
+
+	const cache: Map<string, Buffer> = new Map();
+
+	const read = dev
+		? (file: string) => fs.readFileSync(path.resolve(build_dir, file))
+		: (file: string) => (cache.has(file) ? cache : cache.set(file, fs.readFileSync(path.resolve(build_dir, file)))).get(file)
+
+	return (req: Req, res: Res, next: () => void) => {
+		if (req[IGNORE]) return next();
+
+		if (filter(req)) {
+			const type = lookup(req.path);
+
+			try {
+				const file = decodeURIComponent(req.path.slice(1));
+				const data = read(file);
+
+				res.setHeader('Content-Type', type);
+				res.setHeader('Cache-Control', cache_control);
+				res.end(data);
+			} catch (err) {
+				res.statusCode = 404;
+				res.end('not found');
+			}
+		} else {
+			next();
+		}
+	};
+}
--- a/templates/src/server/middleware/mime-types.md
+++ b/templates/src/server/middleware/mime-types.md
@@ -0,0 +1,767 @@
+application/andrew-inset			ez
+application/applixware				aw
+application/atom+xml				atom
+application/atomcat+xml				atomcat
+application/atomsvc+xml				atomsvc
+application/ccxml+xml				ccxml
+application/cdmi-capability			cdmia
+application/cdmi-container			cdmic
+application/cdmi-domain				cdmid
+application/cdmi-object				cdmio
+application/cdmi-queue				cdmiq
+application/cu-seeme				cu
+application/davmount+xml			davmount
+application/docbook+xml				dbk
+application/dssc+der				dssc
+application/dssc+xml				xdssc
+application/ecmascript				ecma
+application/emma+xml				emma
+application/epub+zip				epub
+application/exi					exi
+application/font-tdpfr				pfr
+application/gml+xml				gml
+application/gpx+xml				gpx
+application/gxf					gxf
+application/hyperstudio				stk
+application/inkml+xml				ink inkml
+application/ipfix				ipfix
+application/java-archive			jar
+application/java-serialized-object		ser
+application/java-vm				class
+application/javascript				js
+application/json				json map
+application/jsonml+json				jsonml
+application/lost+xml				lostxml
+application/mac-binhex40			hqx
+application/mac-compactpro			cpt
+application/mads+xml				mads
+application/marc				mrc
+application/marcxml+xml				mrcx
+application/mathematica				ma nb mb
+application/mathml+xml				mathml
+application/mbox				mbox
+application/mediaservercontrol+xml		mscml
+application/metalink+xml			metalink
+application/metalink4+xml			meta4
+application/mets+xml				mets
+application/mods+xml				mods
+application/mp21				m21 mp21
+application/mp4					mp4s
+application/msword				doc dot
+application/mxf					mxf
+application/octet-stream	bin dms lrf mar so dist distz pkg bpk dump elc deploy
+application/oda					oda
+application/oebps-package+xml			opf
+application/ogg					ogx
+application/omdoc+xml				omdoc
+application/onenote				onetoc onetoc2 onetmp onepkg
+application/oxps				oxps
+application/patch-ops-error+xml			xer
+application/pdf					pdf
+application/pgp-encrypted			pgp
+application/pgp-signature			asc sig
+application/pics-rules				prf
+application/pkcs10				p10
+application/pkcs7-mime				p7m p7c
+application/pkcs7-signature			p7s
+application/pkcs8				p8
+application/pkix-attr-cert			ac
+application/pkix-cert				cer
+application/pkix-crl				crl
+application/pkix-pkipath			pkipath
+application/pkixcmp				pki
+application/pls+xml				pls
+application/postscript				ai eps ps
+application/prs.cww				cww
+application/pskc+xml				pskcxml
+application/rdf+xml				rdf
+application/reginfo+xml				rif
+application/relax-ng-compact-syntax		rnc
+application/resource-lists+xml			rl
+application/resource-lists-diff+xml		rld
+application/rls-services+xml			rs
+application/rpki-ghostbusters			gbr
+application/rpki-manifest			mft
+application/rpki-roa				roa
+application/rsd+xml				rsd
+application/rss+xml				rss
+application/rtf					rtf
+application/sbml+xml				sbml
+application/scvp-cv-request			scq
+application/scvp-cv-response			scs
+application/scvp-vp-request			spq
+application/scvp-vp-response			spp
+application/sdp					sdp
+application/set-payment-initiation		setpay
+application/set-registration-initiation		setreg
+application/shf+xml				shf
+application/smil+xml				smi smil
+application/sparql-query			rq
+application/sparql-results+xml			srx
+application/srgs				gram
+application/srgs+xml				grxml
+application/sru+xml				sru
+application/ssdl+xml				ssdl
+application/ssml+xml				ssml
+application/tei+xml				tei teicorpus
+application/thraud+xml				tfi
+application/timestamped-data			tsd
+application/vnd.3gpp.pic-bw-large		plb
+application/vnd.3gpp.pic-bw-small		psb
+application/vnd.3gpp.pic-bw-var			pvb
+application/vnd.3gpp2.tcap			tcap
+application/vnd.3m.post-it-notes		pwn
+application/vnd.accpac.simply.aso		aso
+application/vnd.accpac.simply.imp		imp
+application/vnd.acucobol			acu
+application/vnd.acucorp				atc acutc
+application/vnd.adobe.air-application-installer-package+zip	air
+application/vnd.adobe.formscentral.fcdt		fcdt
+application/vnd.adobe.fxp			fxp fxpl
+application/vnd.adobe.xdp+xml			xdp
+application/vnd.adobe.xfdf			xfdf
+application/vnd.ahead.space			ahead
+application/vnd.airzip.filesecure.azf		azf
+application/vnd.airzip.filesecure.azs		azs
+application/vnd.amazon.ebook			azw
+application/vnd.americandynamics.acc		acc
+application/vnd.amiga.ami			ami
+application/vnd.android.package-archive		apk
+application/vnd.anser-web-certificate-issue-initiation	cii
+application/vnd.anser-web-funds-transfer-initiation	fti
+application/vnd.antix.game-component		atx
+application/vnd.apple.installer+xml		mpkg
+application/vnd.apple.mpegurl			m3u8
+application/vnd.aristanetworks.swi		swi
+application/vnd.astraea-software.iota		iota
+application/vnd.audiograph			aep
+application/vnd.blueice.multipass		mpm
+application/vnd.bmi				bmi
+application/vnd.businessobjects			rep
+application/vnd.chemdraw+xml			cdxml
+application/vnd.chipnuts.karaoke-mmd		mmd
+application/vnd.cinderella			cdy
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+application/vnd.cloanto.rp9			rp9
+application/vnd.clonk.c4group			c4g c4d c4f c4p c4u
+application/vnd.cluetrust.cartomobile-config		c11amc
+application/vnd.cluetrust.cartomobile-config-pkg	c11amz
+application/vnd.commonspace			csp
+application/vnd.contact.cmsg			cdbcmsg
+application/vnd.cosmocaller			cmc
+application/vnd.crick.clicker			clkx
+application/vnd.crick.clicker.keyboard		clkk
+application/vnd.crick.clicker.palette		clkp
+application/vnd.crick.clicker.template		clkt
+application/vnd.crick.clicker.wordbank		clkw
+application/vnd.criticaltools.wbs+xml		wbs
+application/vnd.ctc-posml			pml
+application/vnd.cups-ppd			ppd
+application/vnd.curl.car			car
+application/vnd.curl.pcurl			pcurl
+application/vnd.dart				dart
+application/vnd.data-vision.rdz			rdz
+application/vnd.dece.data			uvf uvvf uvd uvvd
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+application/vnd.dece.unspecified		uvx uvvx
+application/vnd.dece.zip			uvz uvvz
+application/vnd.denovo.fcselayout-link		fe_launch
+application/vnd.dna				dna
+application/vnd.dolby.mlp			mlp
+application/vnd.dpgraph				dpg
+application/vnd.dreamfactory			dfac
+application/vnd.ds-keypoint			kpxx
+application/vnd.dvb.ait				ait
+application/vnd.dvb.service			svc
+application/vnd.dynageo				geo
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+application/vnd.enliven				nml
+application/vnd.epson.esf			esf
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+application/vnd.epson.salt			slt
+application/vnd.epson.ssf			ssf
+application/vnd.eszigno3+xml			es3 et3
+application/vnd.ezpix-album			ez2
+application/vnd.ezpix-package			ez3
+application/vnd.fdf				fdf
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+application/vnd.fdsn.seed			seed dataless
+application/vnd.flographit			gph
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+application/vnd.framemaker			fm frame maker book
+application/vnd.frogans.fnc			fnc
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+application/vnd.fujitsu.oasys			oas
+application/vnd.fujitsu.oasys2			oa2
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+application/vnd.fujitsu.oasysgp			fg5
+application/vnd.fujitsu.oasysprs		bh2
+application/vnd.fujixerox.ddd			ddd
+application/vnd.fujixerox.docuworks		xdw
+application/vnd.fujixerox.docuworks.binder	xbd
+application/vnd.fuzzysheet			fzs
+application/vnd.genomatix.tuxedo		txd
+application/vnd.geogebra.file			ggb
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+application/vnd.grafeq				gqf gqs
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+application/vnd.groove-help			ghf
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+application/vnd.groove-tool-template		tpl
+application/vnd.groove-vcard			vcg
+application/vnd.hal+xml				hal
+application/vnd.handheld-entertainment+xml	zmm
+application/vnd.hbci				hbci
+application/vnd.hhe.lesson-player		les
+application/vnd.hp-hpgl				hpgl
+application/vnd.hp-hpid				hpid
+application/vnd.hp-hps				hps
+application/vnd.hp-jlyt				jlt
+application/vnd.hp-pcl				pcl
+application/vnd.hp-pclxl			pclxl
+application/vnd.hydrostatix.sof-data		sfd-hdstx
+application/vnd.ibm.minipay			mpy
+application/vnd.ibm.modcap			afp listafp list3820
+application/vnd.ibm.rights-management		irm
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+application/vnd.iccprofile			icc icm
+application/vnd.igloader			igl
+application/vnd.immervision-ivp			ivp
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+application/vnd.intu.qbo			qbo
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+application/vnd.jam				jam
+application/vnd.jcp.javame.midlet-rms		rms
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+application/vnd.kahootz				ktz ktr
+application/vnd.kde.karbon			karbon
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+application/vnd.kde.kpresenter			kpr kpt
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+application/vnd.kenameaapp			htke
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+application/vnd.kinar				kne knp
+application/vnd.koan				skp skd skt skm
+application/vnd.kodak-descriptor		sse
+application/vnd.las.las+xml			lasxml
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+application/vnd.lotus-1-2-3			123
+application/vnd.lotus-approach			apr
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+application/vnd.lotus-notes			nsf
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+application/vnd.lotus-screencam			scm
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+application/vnd.ms-excel			xls xlm xla xlc xlt xlw
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+application/vnd.ms-works			wps wks wcm wdb
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+application/vnd.nokia.n-gage.data		ngdat
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+application/vnd.yellowriver-custom-menu		cmp
+application/vnd.zul				zir zirz
+application/vnd.zzazz.deck+xml			zaz
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+application/winhlp				hlp
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+application/x-apple-diskimage			dmg
+application/x-authorware-bin			aab x32 u32 vox
+application/x-authorware-map			aam
+application/x-authorware-seg			aas
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+application/x-bzip2				bz2 boz
+application/x-cbr				cbr cba cbt cbz cb7
+application/x-cdlink				vcd
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+application/x-chess-pgn				pgn
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+application/x-cpio				cpio
+application/x-csh				csh
+application/x-debian-package			deb udeb
+application/x-dgc-compressed			dgc
+application/x-director			dir dcr dxr cst cct cxt w3d fgd swa
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+application/x-freearc				arc
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+application/x-glulx				ulx
+application/x-gnumeric				gnumeric
+application/x-gramps-xml			gramps
+application/x-gtar				gtar
+application/x-hdf				hdf
+application/x-install-instructions		install
+application/x-iso9660-image			iso
+application/x-java-jnlp-file			jnlp
+application/x-latex				latex
+application/x-lzh-compressed			lzh lha
+application/x-mie				mie
+application/x-mobipocket-ebook			prc mobi
+application/x-ms-application			application
+application/x-ms-shortcut			lnk
+application/x-ms-wmd				wmd
+application/x-ms-wmz				wmz
+application/x-ms-xbap				xbap
+application/x-msaccess				mdb
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+application/x-msclip				clp
+application/x-msdownload			exe dll com bat msi
+application/x-msmediaview			mvb m13 m14
+application/x-msmetafile			wmf wmz emf emz
+application/x-msmoney				mny
+application/x-mspublisher			pub
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+application/x-pkcs7-certreqresp			p7r
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+application/x-sh				sh
+application/x-shar				shar
+application/x-shockwave-flash			swf
+application/x-silverlight-app			xap
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+application/x-stuffitx				sitx
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+application/x-ustar				ustar
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+application/x-x509-ca-cert			der crt
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+audio/vnd.nuera.ecelp7470			ecelp7470
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+audio/x-ms-wma					wma
+audio/x-pn-realaudio				ram ra
+audio/x-pn-realaudio-plugin			rmp
+audio/x-wav					wav
+audio/xm					xm
+chemical/x-cdx					cdx
+chemical/x-cif					cif
+chemical/x-cmdf					cmdf
+chemical/x-cml					cml
+chemical/x-csml					csml
+chemical/x-xyz					xyz
+font/collection					ttc
+font/otf					otf
+font/ttf					ttf
+font/woff					woff
+font/woff2					woff2
+image/bmp					bmp
+image/cgm					cgm
+image/g3fax					g3
+image/gif					gif
+image/ief					ief
+image/jpeg					jpeg jpg jpe
+image/ktx					ktx
+image/png					png
+image/prs.btif					btif
+image/sgi					sgi
+image/svg+xml					svg svgz
+image/tiff					tiff tif
+image/vnd.adobe.photoshop			psd
+image/vnd.dece.graphic				uvi uvvi uvg uvvg
+image/vnd.djvu					djvu djv
+image/vnd.dvb.subtitle				sub
+image/vnd.dwg					dwg
+image/vnd.dxf					dxf
+image/vnd.fastbidsheet				fbs
+image/vnd.fpx					fpx
+image/vnd.fst					fst
+image/vnd.fujixerox.edmics-mmr			mmr
+image/vnd.fujixerox.edmics-rlc			rlc
+image/vnd.ms-modi				mdi
+image/vnd.ms-photo				wdp
+image/vnd.net-fpx				npx
+image/vnd.wap.wbmp				wbmp
+image/vnd.xiff					xif
+image/webp					webp
+image/x-3ds					3ds
+image/x-cmu-raster				ras
+image/x-cmx					cmx
+image/x-freehand				fh fhc fh4 fh5 fh7
+image/x-icon					ico
+image/x-mrsid-image				sid
+image/x-pcx					pcx
+image/x-pict					pic pct
+image/x-portable-anymap				pnm
+image/x-portable-bitmap				pbm
+image/x-portable-graymap			pgm
+image/x-portable-pixmap				ppm
+image/x-rgb					rgb
+image/x-tga					tga
+image/x-xbitmap					xbm
+image/x-xpixmap					xpm
+image/x-xwindowdump				xwd
+message/rfc822					eml mime
+model/iges					igs iges
+model/mesh					msh mesh silo
+model/vnd.collada+xml				dae
+model/vnd.dwf					dwf
+model/vnd.gdl					gdl
+model/vnd.gtw					gtw
+model/vnd.mts					mts
+model/vnd.vtu					vtu
+model/vrml					wrl vrml
+model/x3d+binary				x3db x3dbz
+model/x3d+vrml					x3dv x3dvz
+model/x3d+xml					x3d x3dz
+text/cache-manifest				appcache
+text/calendar					ics ifb
+text/css					css
+text/csv					csv
+text/html					html htm
+text/n3						n3
+text/plain					txt text conf def list log in
+text/prs.lines.tag				dsc
+text/richtext					rtx
+text/sgml					sgml sgm
+text/tab-separated-values			tsv
+text/troff					t tr roff man me ms
+text/turtle					ttl
+text/uri-list					uri uris urls
+text/vcard					vcard
+text/vnd.curl					curl
+text/vnd.curl.dcurl				dcurl
+text/vnd.curl.mcurl				mcurl
+text/vnd.curl.scurl				scurl
+text/vnd.dvb.subtitle				sub
+text/vnd.fly					fly
+text/vnd.fmi.flexstor				flx
+text/vnd.graphviz				gv
+text/vnd.in3d.3dml				3dml
+text/vnd.in3d.spot				spot
+text/vnd.sun.j2me.app-descriptor		jad
+text/vnd.wap.wml				wml
+text/vnd.wap.wmlscript				wmls
+text/x-asm					s asm
+text/x-c					c cc cxx cpp h hh dic
+text/x-fortran					f for f77 f90
+text/x-java-source				java
+text/x-nfo					nfo
+text/x-opml					opml
+text/x-pascal					p pas
+text/x-setext					etx
+text/x-sfv					sfv
+text/x-uuencode					uu
+text/x-vcalendar				vcs
+text/x-vcard					vcf
+video/3gpp					3gp
+video/3gpp2					3g2
+video/h261					h261
+video/h263					h263
+video/h264					h264
+video/jpeg					jpgv
+video/jpm					jpm jpgm
+video/mj2					mj2 mjp2
+video/mp4					mp4 mp4v mpg4
+video/mpeg					mpeg mpg mpe m1v m2v
+video/ogg					ogv
+video/quicktime					qt mov
+video/vnd.dece.hd				uvh uvvh
+video/vnd.dece.mobile				uvm uvvm
+video/vnd.dece.pd				uvp uvvp
+video/vnd.dece.sd				uvs uvvs
+video/vnd.dece.video				uvv uvvv
+video/vnd.dvb.file				dvb
+video/vnd.fvt					fvt
+video/vnd.mpegurl				mxu m4u
+video/vnd.ms-playready.media.pyv		pyv
+video/vnd.uvvu.mp4				uvu uvvu
+video/vnd.vivo					viv
+video/webm					webm
+video/x-f4v					f4v
+video/x-fli					fli
+video/x-flv					flv
+video/x-m4v					m4v
+video/x-matroska				mkv mk3d mks
+video/x-mng					mng
+video/x-ms-asf					asf asx
+video/x-ms-vob					vob
+video/x-ms-wm					wm
+video/x-ms-wmv					wmv
+video/x-ms-wmx					wmx
+video/x-ms-wvx					wvx
+video/x-msvideo					avi
+video/x-sgi-movie				movie
+video/x-smv					smv
+x-conference/x-cooltalk				ice
--- a/templates/src/server/middleware/mime.ts
+++ b/templates/src/server/middleware/mime.ts
@@ -0,0 +1,20 @@
+import mime_raw from './mime-types.md';
+
+const map: Map<string, string> = new Map();
+
+mime_raw.split('\n').forEach((row: string) => {
+	const match = /(.+?)\t+(.+)/.exec(row);
+	if (!match) return;
+
+	const type = match[1];
+	const extensions = match[2].split(' ');
+
+	extensions.forEach(ext => {
+		map.set(ext, type);
+	});
+});
+
+export function lookup(file: string) {
+	const match = /\.([^\.]+)$/.exec(file);
+	return match && map.get(match[1]);
+}
--- a/templates/src/server/middleware/types.ts
+++ b/templates/src/server/middleware/types.ts
@@ -0,0 +1,69 @@
+import { ClientRequest, ServerResponse } from 'http';
+
+export type ServerRoute = {
+	pattern: RegExp;
+	handlers: Record<string, Handler>;
+	params: (match: RegExpMatchArray) => Record<string, string>;
+};
+
+export type Page = {
+	pattern: RegExp;
+	parts: Array<{
+		name: string;
+		component: Component;
+		params?: (match: RegExpMatchArray) => Record<string, string>;
+	}>
+};
+
+export type Manifest = {
+	server_routes: ServerRoute[];
+	pages: Page[];
+	root: Component;
+	error: Component;
+}
+
+export type Handler = (req: Req, res: Res, next: () => void) => void;
+
+export type Store = {
+	get: () => any
+};
+
+export type Props = {
+	path: string;
+	query: Record<string, string>;
+	params: Record<string, string>;
+	error?: { message: string };
+	status?: number;
+	child: {
+		segment: string;
+		component: Component;
+		props: Props;
+	};
+	[key: string]: any;
+};
+
+export interface Req extends ClientRequest {
+	url: string;
+	baseUrl: string;
+	originalUrl: string;
+	method: string;
+	path: string;
+	params: Record<string, string>;
+	query: Record<string, string>;
+	headers: Record<string, string>;
+}
+
+export interface Res extends ServerResponse {
+	write: (data: any) => void;
+}
+
+export { ServerResponse };
+
+interface Component {
+	render: (data: any, opts: { store: Store }) => {
+		head: string;
+		css: { code: string, map: any };
+		html: string
+	},
+	preload: (data: any) => any | Promise<any>
+}
--- a/templates/src/server/placeholders.ts
+++ b/templates/src/server/placeholders.ts
@@ -0,0 +1,11 @@
+import { Manifest } from './types';
+
+export const manifest: Manifest = __MANIFEST__;
+
+export const build_dir = __BUILD__DIR__;
+
+export const src_dir = __SRC__DIR__;
+
+export const dev = __DEV__;
+
+export const IGNORE = '__SAPPER__IGNORE__';
--- a/test/apps/AppRunner.ts
+++ b/test/apps/AppRunner.ts
@@ -0,0 +1,132 @@
+import * as path from 'path';
+import * as puppeteer from 'puppeteer';
+import * as ports from 'port-authority';
+import { fork, ChildProcess } from 'child_process';
+
+declare const start: () => Promise<void>;
+declare const prefetchRoutes: () => Promise<void>;
+declare const prefetch: (href: string) => Promise<void>;
+declare const goto: (href: string) => Promise<void>;
+
+type StartOpts = {
+	requestInterceptor?: (interceptedRequst: puppeteer.Request) => any
+};
+
+export class AppRunner {
+	cwd: string;
+	entry: string;
+	port: number;
+	proc: ChildProcess;
+	messages: any[];
+
+	browser: puppeteer.Browser;
+	page: puppeteer.Page;
+
+	constructor(cwd: string, entry: string) {
+		this.cwd = cwd;
+		this.entry = path.join(cwd, entry);
+		this.messages = [];
+	}
+
+	async start({ requestInterceptor }: StartOpts = {}) {
+		this.port = await ports.find(3000);
+
+		this.proc = fork(this.entry, [], {
+			cwd: this.cwd,
+			env: {
+				PORT: String(this.port)
+			}
+		});
+
+		this.proc.on('message', message => {
+			if (!message.__sapper__) return;
+			this.messages.push(message);
+		});
+
+		this.browser = await puppeteer.launch({ args: ['--no-sandbox'] });
+
+		this.page = await this.browser.newPage();
+		this.page.on('console', msg => {
+			const text = msg.text();
+
+			if (!text.startsWith('Failed to load resource')) {
+				console.log(text);
+			}
+		});
+
+		if (requestInterceptor) {
+			await this.page.setRequestInterception(true);
+			this.page.on('request', requestInterceptor);
+		}
+
+		return {
+			page: this.page,
+			base: `http://localhost:${this.port}`,
+
+			// helpers
+			start: () => this.page.evaluate(() => start()),
+			prefetchRoutes: () => this.page.evaluate(() => prefetchRoutes()),
+			prefetch: (href: string) => this.page.evaluate((href: string) => prefetch(href), href),
+			goto: (href: string) => this.page.evaluate((href: string) => goto(href), href),
+			title: () => this.page.$eval('h1', node => node.textContent)
+		};
+	}
+
+	capture(fn: () => any): Promise<string[]> {
+		return new Promise((fulfil, reject) => {
+			const requests: string[] = [];
+			const pending: Set<string> = new Set();
+			let done = false;
+
+			function handle_request(request: puppeteer.Request) {
+				const url = request.url();
+				requests.push(url);
+				pending.add(url);
+			}
+
+			function handle_requestfinished(request: puppeteer.Request) {
+				const url = request.url();
+				pending.delete(url);
+
+				if (done && pending.size === 0) {
+					cleanup();
+					fulfil(requests);
+				}
+			}
+
+			function handle_requestfailed(request: puppeteer.Request) {
+				cleanup();
+				reject(new Error(`failed to fetch ${request.url()}`))
+			}
+
+			const cleanup = () => {
+				this.page.removeListener('request', handle_request);
+				this.page.removeListener('requestfinished', handle_requestfinished);
+				this.page.removeListener('requestfailed', handle_requestfailed);
+			};
+
+			this.page.on('request', handle_request);
+			this.page.on('requestfinished', handle_requestfinished);
+			this.page.on('requestfailed', handle_requestfailed);
+
+			return Promise.resolve(fn()).then(() => {
+				if (pending.size === 0) {
+					cleanup();
+					fulfil(requests);
+				}
+
+				done = true;
+			});
+		});
+	}
+
+	end() {
+		return Promise.all([
+			this.browser.close(),
+			new Promise(fulfil => {
+				this.proc.once('exit', fulfil);
+				this.proc.kill();
+			})
+		]);
+	}
+}
--- a/test/apps/basics/rollup.config.js
+++ b/test/apps/basics/rollup.config.js
@@ -0,0 +1,64 @@
+import resolve from 'rollup-plugin-node-resolve';
+import replace from 'rollup-plugin-replace';
+import svelte from 'rollup-plugin-svelte';
+
+const mode = process.env.NODE_ENV;
+const dev = mode === 'development';
+
+const config = require('../../../config/rollup.js');
+
+export default {
+	client: {
+		input: config.client.input(),
+		output: config.client.output(),
+		plugins: [
+			replace({
+				'process.browser': true,
+				'process.env.NODE_ENV': JSON.stringify(mode)
+			}),
+			svelte({
+				dev,
+				hydratable: true,
+				emitCss: true
+			}),
+			resolve()
+		],
+
+		// temporary, pending Rollup 1.0
+		experimentalCodeSplitting: true
+	},
+
+	server: {
+		input: config.server.input(),
+		output: config.server.output(),
+		plugins: [
+			replace({
+				'process.browser': false,
+				'process.env.NODE_ENV': JSON.stringify(mode)
+			}),
+			svelte({
+				generate: 'ssr',
+				dev
+			}),
+			resolve({
+				preferBuiltins: true
+			})
+		],
+		external: ['sirv', 'polka'],
+
+		// temporary, pending Rollup 1.0
+		experimentalCodeSplitting: true
+	},
+
+	serviceworker: {
+		input: config.serviceworker.input(),
+		output: config.serviceworker.output(),
+		plugins: [
+			resolve(),
+			replace({
+				'process.browser': true,
+				'process.env.NODE_ENV': JSON.stringify(mode)
+			})
+		]
+	}
+};
--- a/test/apps/basics/src/client.js
+++ b/test/apps/basics/src/client.js
@@ -0,0 +1,9 @@
+import * as sapper from '../__sapper__/client.js';
+
+window.start = () => sapper.start({
+	target: document.querySelector('#sapper')
+});
+
+window.prefetchRoutes = () => sapper.prefetchRoutes();
+window.prefetch = href => sapper.prefetch(href);
+window.goto = href => sapper.goto(href);
--- a/test/apps/basics/src/routes/[slug].html
+++ b/test/apps/basics/src/routes/[slug].html
@@ -0,0 +1 @@
+<h1>{params.slug.toUpperCase()}</h1>
--- a/test/apps/basics/src/routes/_error.html
+++ b/test/apps/basics/src/routes/_error.html
@@ -0,0 +1,3 @@
+<h1>{status}</h1>
+
+<p>{error.message}</p>
--- a/test/apps/basics/src/routes/a.html
+++ b/test/apps/basics/src/routes/a.html
@@ -0,0 +1 @@
+<h1>a</h1>
--- a/test/apps/basics/src/routes/ambiguous/[slug].html
+++ b/test/apps/basics/src/routes/ambiguous/[slug].html
--- a/test/apps/basics/src/routes/ambiguous/[slug].json.js
+++ b/test/apps/basics/src/routes/ambiguous/[slug].json.js
@@ -0,0 +1,3 @@
+export function get(req, res) {
+	res.end(req.params.slug);
+}
--- a/test/apps/basics/src/routes/b/index.html
+++ b/test/apps/basics/src/routes/b/index.html
@@ -0,0 +1,11 @@
+<h1>{letter}</h1>
+
+<script>
+	export default {
+		preload() {
+			return this.fetch('b.json').then(r => r.json()).then(letter => {
+				return { letter };
+			});
+		}
+	};
+</script>
--- a/test/apps/basics/src/routes/b/index.json.js
+++ b/test/apps/basics/src/routes/b/index.json.js
@@ -0,0 +1,3 @@
+export function get(req, res) {
+	res.end(JSON.stringify('b'));
+}
--- a/test/apps/basics/src/routes/const.html
+++ b/test/apps/basics/src/routes/const.html
@@ -0,0 +1 @@
+<h1>reserved words are okay as routes</h1>
--- a/test/apps/basics/src/routes/delete-test/[id].json.js
+++ b/test/apps/basics/src/routes/delete-test/[id].json.js
@@ -0,0 +1,9 @@
+export function del(req, res) {
+	res.writeHead(200, {
+		'Content-Type': 'application/json'
+	});
+
+	res.end(JSON.stringify({
+		id: req.params.id
+	}));
+}
--- a/test/apps/basics/src/routes/delete-test/index.html
+++ b/test/apps/basics/src/routes/delete-test/index.html
@@ -0,0 +1,19 @@
+<button class='del' on:click='del()'>delete</button>
+
+<script>
+	export default {
+		oncreate() {
+			window.deleted = null;
+		},
+
+		methods: {
+			del() {
+				fetch(`delete-test/42.json`, { method: 'DELETE' })
+					.then(r => r.json())
+					.then(data => {
+						window.deleted = data;
+					});
+			}
+		}
+	};
+</script>
--- a/test/apps/basics/src/routes/echo-query/index.html
+++ b/test/apps/basics/src/routes/echo-query/index.html
@@ -0,0 +1 @@
+<h1>{JSON.stringify(query)}</h1>
--- a/test/apps/basics/src/routes/index.html
+++ b/test/apps/basics/src/routes/index.html
@@ -0,0 +1,8 @@
+<h1>Great success!</h1>
+
+<a href="a">a</a>
+<a href="ambiguous/ok.json">ok</a>
+<a href="echo-query?message">ok</a>
+<a href="echo-query?p=one&p=two">ok</a>
+
+<div class='hydrate-test'></div>
--- a/test/apps/basics/src/routes/unsafe-replacement.html
+++ b/test/apps/basics/src/routes/unsafe-replacement.html
@@ -0,0 +1,9 @@
+$&
+
+<script>
+	export default {
+		preload() {
+			return '$&';
+		}
+	};
+</script>
--- a/test/apps/basics/src/server.js
+++ b/test/apps/basics/src/server.js
@@ -0,0 +1,8 @@
+import polka from 'polka';
+import * as sapper from '../__sapper__/server.js';
+
+const { PORT } = process.env;
+
+polka()
+	.use(sapper.middleware())
+	.listen(PORT);
--- a/test/apps/basics/src/service-worker.js
+++ b/test/apps/basics/src/service-worker.js
@@ -0,0 +1,82 @@
+import { timestamp, files, shell, routes } from '../__sapper__/service-worker.js';
+
+const ASSETS = `cache${timestamp}`;
+
+// `shell` is an array of all the files generated by webpack,
+// `files` is an array of everything in the `static` directory
+const to_cache = shell.concat(ASSETS);
+const cached = new Set(to_cache);
+
+self.addEventListener('install', event => {
+	event.waitUntil(
+		caches
+			.open(ASSETS)
+			.then(cache => cache.addAll(to_cache))
+			.then(() => {
+				self.skipWaiting();
+			})
+	);
+});
+
+self.addEventListener('activate', event => {
+	event.waitUntil(
+		caches.keys().then(async keys => {
+			// delete old caches
+			for (const key of keys) {
+				if (key !== ASSETS) await caches.delete(key);
+			}
+
+			self.clients.claim();
+		})
+	);
+});
+
+self.addEventListener('fetch', event => {
+	if (event.request.method !== 'GET') return;
+
+	const url = new URL(event.request.url);
+
+	// don't try to handle e.g. data: URIs
+	if (!url.protocol.startsWith('http')) return;
+
+	// ignore dev server requests
+	if (url.hostname === self.location.hostname && url.port !== self.location.port) return;
+
+	// always serve assets and webpack-generated files from cache
+	if (url.host === self.location.host && cached.has(url.pathname)) {
+		event.respondWith(caches.match(event.request));
+		return;
+	}
+
+	// for pages, you might want to serve a shell `index.html` file,
+	// which Sapper has generated for you. It's not right for every
+	// app, but if it's right for yours then uncomment this section
+	/*
+	if (url.origin === self.origin && routes.find(route => route.pattern.test(url.pathname))) {
+		event.respondWith(caches.match('/index.html'));
+		return;
+	}
+	*/
+
+	if (event.request.cache === 'only-if-cached') return;
+
+	// for everything else, try the network first, falling back to
+	// cache if the user is offline. (If the pages never change, you
+	// might prefer a cache-first approach to a network-first one.)
+	event.respondWith(
+		caches
+			.open(`offline${timestamp}`)
+			.then(async cache => {
+				try {
+					const response = await fetch(event.request);
+					cache.put(event.request, response.clone());
+					return response;
+				} catch(err) {
+					const response = await cache.match(event.request);
+					if (response) return response;
+
+					throw err;
+				}
+			})
+	);
+});
--- a/test/apps/basics/src/template.html
+++ b/test/apps/basics/src/template.html
@@ -0,0 +1,14 @@
+<!doctype html>
+<html lang="en">
+<head>
+	<meta charset='utf-8'>
+
+	%sapper.base%
+	%sapper.styles%
+	%sapper.head%
+</head>
+<body>
+	<div id='sapper'>%sapper.html%</div>
+	%sapper.scripts%
+</body>
+</html>
--- a/test/apps/basics/test.ts
+++ b/test/apps/basics/test.ts
@@ -0,0 +1,268 @@
+import * as assert from 'assert';
+import * as puppeteer from 'puppeteer';
+import * as http from 'http';
+import { build } from '../../../api';
+import { AppRunner } from '../AppRunner';
+import { wait } from '../../utils';
+
+declare let deleted: { id: number };
+declare let el: any;
+
+describe('basics', function() {
+	this.timeout(10000);
+
+	let runner: AppRunner;
+	let page: puppeteer.Page;
+	let base: string;
+
+	// helpers
+	let start: () => Promise<void>;
+	let prefetchRoutes: () => Promise<void>;
+	let prefetch: (href: string) => Promise<void>;
+	let goto: (href: string) => Promise<void>;
+
+	// hooks
+	before(async () => {
+		await build({ cwd: __dirname });
+
+		runner = new AppRunner(__dirname, '__sapper__/build/server/server.js');
+		({ base, page, start, prefetchRoutes, prefetch, goto } = await runner.start());
+	});
+
+	after(() => runner.end());
+
+	const title = () => page.$eval('h1', node => node.textContent);
+
+	it('serves /', async () => {
+		await page.goto(base);
+
+		assert.equal(
+			await title(),
+			'Great success!'
+		);
+	});
+
+	it('serves /?', async () => {
+		await page.goto(`${base}?`);
+
+		assert.equal(
+			await title(),
+			'Great success!'
+		);
+	});
+
+	it('serves static route', async () => {
+		await page.goto(`${base}/a`);
+
+		assert.equal(
+			await title(),
+			'a'
+		);
+	});
+
+	it('serves static route from dir/index.html file', async () => {
+		await page.goto(`${base}/b`);
+
+		assert.equal(
+			await title(),
+			'b'
+		);
+	});
+
+	it('serves dynamic route', async () => {
+		await page.goto(`${base}/test-slug`);
+
+		assert.equal(
+			await title(),
+			'TEST-SLUG'
+		);
+	});
+
+	it('navigates to a new page without reloading', async () => {
+		await page.goto(base);
+		await start();
+		await prefetchRoutes();
+
+		const requests: string[] = await runner.capture(async () => {
+			await page.click('a[href="a"]');
+		});
+
+		assert.deepEqual(requests, []);
+
+		assert.equal(
+			await title(),
+			'a'
+		);
+	});
+
+	it('navigates programmatically', async () => {
+		await page.goto(`${base}/a`);
+		await start();
+
+		await goto('b');
+
+		assert.equal(
+			await title(),
+			'b'
+		);
+	});
+
+	it('prefetches programmatically', async () => {
+		await page.goto(`${base}/a`);
+		await start();
+
+		const requests = await runner.capture(() => prefetch('b'));
+
+		assert.equal(requests.length, 2);
+		assert.equal(requests[1], `${base}/b.json`);
+	});
+
+
+	// TODO equivalent test for a webpack app
+	it('sets Content-Type, Link...modulepreload, and Cache-Control headers', () => {
+		return new Promise((fulfil, reject) => {
+			const req = http.get(base, res => {
+				try {
+					const { headers } = res;
+
+					assert.equal(
+						headers['content-type'],
+						'text/html'
+					);
+
+					assert.equal(
+						headers['cache-control'],
+						'max-age=600'
+					);
+
+					// TODO preload more than just the entry point
+					const regex = /<\/client\/client\.\w+\.js>;rel="modulepreload"/;
+					const link = <string>headers['link'];
+
+					assert.ok(regex.test(link), link);
+
+					fulfil();
+				} catch (err) {
+					reject(err);
+				}
+			});
+
+			req.on('error', reject);
+		});
+	});
+
+	it('calls a delete handler', async () => {
+		await page.goto(`${base}/delete-test`);
+		await start();
+
+		await page.click('.del');
+		await page.waitForFunction(() => deleted);
+
+		assert.equal(await page.evaluate(() => deleted.id), 42);
+	});
+
+	it('hydrates initial route', async () => {
+		await page.goto(base);
+
+		await page.evaluate(() => {
+			el = document.querySelector('.hydrate-test');
+		});
+
+		await start();
+
+		assert.ok(await page.evaluate(() => {
+			return document.querySelector('.hydrate-test') === el;
+		}));
+	});
+
+	it('does not attempt client-side navigation to server routes', async () => {
+		await page.goto(base);
+		await start();
+		await prefetchRoutes();
+
+		await page.click(`[href="ambiguous/ok.json"]`);
+		await wait(50);
+
+		assert.equal(
+			await page.evaluate(() => document.body.textContent),
+			'ok'
+		);
+	});
+
+	it('allows reserved words as route names', async () => {
+		await page.goto(`${base}/const`);
+		await start();
+
+		assert.equal(
+			await title(),
+			'reserved words are okay as routes'
+		);
+	});
+
+	it('accepts value-less query string parameter on server', async () => {
+		await page.goto(`${base}/echo-query?message`);
+
+		assert.equal(
+			await title(),
+			'{"message":""}'
+		);
+	});
+
+	it('accepts value-less query string parameter on client', async () => {
+		await page.goto(base);
+		await start();
+		await prefetchRoutes();
+
+		await page.click('a[href="echo-query?message"]')
+
+		assert.equal(
+			await title(),
+			'{"message":""}'
+		);
+	});
+
+	it('accepts duplicated query string parameter on server', async () => {
+		await page.goto(`${base}/echo-query?p=one&p=two`);
+
+		assert.equal(
+			await title(),
+			'{"p":["one","two"]}'
+		);
+	});
+
+	it('accepts duplicated query string parameter on client', async () => {
+		await page.goto(base);
+		await start();
+		await prefetchRoutes();
+
+		await page.click('a[href="echo-query?p=one&p=two"]')
+
+		assert.equal(
+			await title(),
+			'{"p":["one","two"]}'
+		);
+	});
+
+	// skipped because Nightmare doesn't seem to focus the <a> correctly
+	it('resets the active element after navigation', async () => {
+		await page.goto(base);
+		await start();
+		await prefetchRoutes();
+
+		await page.click('[href="a"]');
+		await wait(50);
+
+		assert.equal(
+			await page.evaluate(() => document.activeElement.nodeName),
+			'BODY'
+		);
+	});
+
+	it('replaces %sapper.xxx% tags safely', async () => {
+		await page.goto(`${base}/unsafe-replacement`);
+		await start();
+
+		const html = await page.evaluate(() => document.body.innerHTML);
+		assert.equal(html.indexOf('%sapper'), -1);
+	});
+});
--- a/test/apps/credentials/rollup.config.js
+++ b/test/apps/credentials/rollup.config.js
@@ -0,0 +1,64 @@
+import resolve from 'rollup-plugin-node-resolve';
+import replace from 'rollup-plugin-replace';
+import svelte from 'rollup-plugin-svelte';
+
+const mode = process.env.NODE_ENV;
+const dev = mode === 'development';
+
+const config = require('../../../config/rollup.js');
+
+export default {
+	client: {
+		input: config.client.input(),
+		output: config.client.output(),
+		plugins: [
+			replace({
+				'process.browser': true,
+				'process.env.NODE_ENV': JSON.stringify(mode)
+			}),
+			svelte({
+				dev,
+				hydratable: true,
+				emitCss: true
+			}),
+			resolve()
+		],
+
+		// temporary, pending Rollup 1.0
+		experimentalCodeSplitting: true
+	},
+
+	server: {
+		input: config.server.input(),
+		output: config.server.output(),
+		plugins: [
+			replace({
+				'process.browser': false,
+				'process.env.NODE_ENV': JSON.stringify(mode)
+			}),
+			svelte({
+				generate: 'ssr',
+				dev
+			}),
+			resolve({
+				preferBuiltins: true
+			})
+		],
+		external: ['sirv', 'polka', 'cookie'],
+
+		// temporary, pending Rollup 1.0
+		experimentalCodeSplitting: true
+	},
+
+	serviceworker: {
+		input: config.serviceworker.input(),
+		output: config.serviceworker.output(),
+		plugins: [
+			resolve(),
+			replace({
+				'process.browser': true,
+				'process.env.NODE_ENV': JSON.stringify(mode)
+			})
+		]
+	}
+};
--- a/test/apps/credentials/src/client.js
+++ b/test/apps/credentials/src/client.js
@@ -0,0 +1,9 @@
+import * as sapper from '../__sapper__/client.js';
+
+window.start = () => sapper.start({
+	target: document.querySelector('#sapper')
+});
+
+window.prefetchRoutes = () => sapper.prefetchRoutes();
+window.prefetch = href => sapper.prefetch(href);
+window.goto = href => sapper.goto(href);
--- a/test/apps/credentials/src/routes/_error.html
+++ b/test/apps/credentials/src/routes/_error.html
@@ -0,0 +1,3 @@
+<h1>{status}</h1>
+
+<p>{error.message}</p>
--- a/test/apps/credentials/src/routes/credentials/index.html
+++ b/test/apps/credentials/src/routes/credentials/index.html
@@ -0,0 +1,11 @@
+<h1>{message}</h1>
+
+<script>
+	export default {
+		preload({ query }) {
+			return this.fetch(`credentials/test.json`, {
+				credentials: query.creds
+			}).then(r => r.json());
+		}
+	};
+</script>
--- a/test/apps/credentials/src/routes/credentials/test.json.js
+++ b/test/apps/credentials/src/routes/credentials/test.json.js
@@ -0,0 +1,23 @@
+import cookie from 'cookie';
+
+export function get(req, res) {
+	if (req.headers.cookie) {
+		const cookies = cookie.parse(req.headers.cookie);
+
+		res.writeHead(200, {
+			'Content-Type': 'application/json'
+		});
+
+		res.end(JSON.stringify({
+			message: `a: ${cookies.a}, b: ${cookies.b}, max-age: ${cookies['max-age']}`
+		}));
+	} else {
+		res.writeHead(403, {
+			'Content-Type': 'application/json'
+		});
+
+		res.end(JSON.stringify({
+			message: 'unauthorized'
+		}));
+	}
+}
--- a/test/apps/credentials/src/routes/index.html
+++ b/test/apps/credentials/src/routes/index.html
@@ -0,0 +1,3 @@
+<h1>Great success!</h1>
+
+<a href="credentials?creds=include">link</a>
--- a/test/apps/credentials/src/server.js
+++ b/test/apps/credentials/src/server.js
@@ -0,0 +1,13 @@
+import polka from 'polka';
+import * as sapper from '../__sapper__/server.js';
+
+const { PORT } = process.env;
+
+polka()
+	.use((req, res, next) => {
+		// set test cookie
+		res.setHeader('Set-Cookie', ['a=1; Max-Age=3600', 'b=2; Max-Age=3600']);
+		next();
+	})
+	.use(sapper.middleware())
+	.listen(PORT);
--- a/test/apps/credentials/src/service-worker.js
+++ b/test/apps/credentials/src/service-worker.js
@@ -0,0 +1,82 @@
+import { timestamp, files, shell, routes } from '../__sapper__/service-worker.js';
+
+const ASSETS = `cache${timestamp}`;
+
+// `shell` is an array of all the files generated by webpack,
+// `files` is an array of everything in the `static` directory
+const to_cache = shell.concat(ASSETS);
+const cached = new Set(to_cache);
+
+self.addEventListener('install', event => {
+	event.waitUntil(
+		caches
+			.open(ASSETS)
+			.then(cache => cache.addAll(to_cache))
+			.then(() => {
+				self.skipWaiting();
+			})
+	);
+});
+
+self.addEventListener('activate', event => {
+	event.waitUntil(
+		caches.keys().then(async keys => {
+			// delete old caches
+			for (const key of keys) {
+				if (key !== ASSETS) await caches.delete(key);
+			}
+
+			self.clients.claim();
+		})
+	);
+});
+
+self.addEventListener('fetch', event => {
+	if (event.request.method !== 'GET') return;
+
+	const url = new URL(event.request.url);
+
+	// don't try to handle e.g. data: URIs
+	if (!url.protocol.startsWith('http')) return;
+
+	// ignore dev server requests
+	if (url.hostname === self.location.hostname && url.port !== self.location.port) return;
+
+	// always serve assets and webpack-generated files from cache
+	if (url.host === self.location.host && cached.has(url.pathname)) {
+		event.respondWith(caches.match(event.request));
+		return;
+	}
+
+	// for pages, you might want to serve a shell `index.html` file,
+	// which Sapper has generated for you. It's not right for every
+	// app, but if it's right for yours then uncomment this section
+	/*
+	if (url.origin === self.origin && routes.find(route => route.pattern.test(url.pathname))) {
+		event.respondWith(caches.match('/index.html'));
+		return;
+	}
+	*/
+
+	if (event.request.cache === 'only-if-cached') return;
+
+	// for everything else, try the network first, falling back to
+	// cache if the user is offline. (If the pages never change, you
+	// might prefer a cache-first approach to a network-first one.)
+	event.respondWith(
+		caches
+			.open(`offline${timestamp}`)
+			.then(async cache => {
+				try {
+					const response = await fetch(event.request);
+					cache.put(event.request, response.clone());
+					return response;
+				} catch(err) {
+					const response = await cache.match(event.request);
+					if (response) return response;
+
+					throw err;
+				}
+			})
+	);
+});
--- a/test/apps/credentials/src/template.html
+++ b/test/apps/credentials/src/template.html
@@ -0,0 +1,14 @@
+<!doctype html>
+<html lang="en">
+<head>
+	<meta charset='utf-8'>
+
+	%sapper.base%
+	%sapper.styles%
+	%sapper.head%
+</head>
+<body>
+	<div id='sapper'>%sapper.html%</div>
+	%sapper.scripts%
+</body>
+</html>
--- a/test/apps/credentials/test.ts
+++ b/test/apps/credentials/test.ts
@@ -0,0 +1,59 @@
+import * as assert from 'assert';
+import * as puppeteer from 'puppeteer';
+import { build } from '../../../api';
+import { wait } from '../../utils';
+import { AppRunner } from '../AppRunner';
+
+describe('credentials', function() {
+	this.timeout(10000);
+
+	let runner: AppRunner;
+	let page: puppeteer.Page;
+	let base: string;
+
+	// helpers
+	let start: () => Promise<void>;
+	let prefetchRoutes: () => Promise<void>;
+
+	// hooks
+	before(async () => {
+		await build({ cwd: __dirname });
+
+		runner = new AppRunner(__dirname, '__sapper__/build/server/server.js');
+		({ base, page, start, prefetchRoutes } = await runner.start());
+	});
+
+	after(() => runner.end());
+
+	it('sends cookies when using this.fetch with credentials: "include"', async () => {
+		await page.goto(`${base}/credentials?creds=include`);
+
+		assert.equal(
+			await page.$eval('h1', node => node.textContent),
+			'a: 1, b: 2, max-age: undefined'
+		);
+	});
+
+	it('does not send cookies when using this.fetch without credentials', async () => {
+		await page.goto(`${base}/credentials`);
+
+		assert.equal(
+			await page.$eval('h1', node => node.textContent),
+			'unauthorized'
+		);
+	});
+
+	it('delegates to fetch on the client', async () => {
+		await page.goto(base)
+		await start();
+		await prefetchRoutes();
+
+		await page.click('[href="credentials?creds=include"]');
+		await wait(50);
+
+		assert.equal(
+			await page.$eval('h1', node => node.textContent),
+			'a: 1, b: 2, max-age: undefined'
+		);
+	});
+});
--- a/test/apps/css/rollup.config.js
+++ b/test/apps/css/rollup.config.js
@@ -0,0 +1,64 @@
+import resolve from 'rollup-plugin-node-resolve';
+import replace from 'rollup-plugin-replace';
+import svelte from 'rollup-plugin-svelte';
+
+const mode = process.env.NODE_ENV;
+const dev = mode === 'development';
+
+const config = require('../../../config/rollup.js');
+
+export default {
+	client: {
+		input: config.client.input(),
+		output: config.client.output(),
+		plugins: [
+			replace({
+				'process.browser': true,
+				'process.env.NODE_ENV': JSON.stringify(mode)
+			}),
+			svelte({
+				dev,
+				hydratable: true,
+				emitCss: true
+			}),
+			resolve()
+		],
+
+		// temporary, pending Rollup 1.0
+		experimentalCodeSplitting: true
+	},
+
+	server: {
+		input: config.server.input(),
+		output: config.server.output(),
+		plugins: [
+			replace({
+				'process.browser': false,
+				'process.env.NODE_ENV': JSON.stringify(mode)
+			}),
+			svelte({
+				generate: 'ssr',
+				dev
+			}),
+			resolve({
+				preferBuiltins: true
+			})
+		],
+		external: ['sirv', 'polka'],
+
+		// temporary, pending Rollup 1.0
+		experimentalCodeSplitting: true
+	},
+
+	serviceworker: {
+		input: config.serviceworker.input(),
+		output: config.serviceworker.output(),
+		plugins: [
+			resolve(),
+			replace({
+				'process.browser': true,
+				'process.env.NODE_ENV': JSON.stringify(mode)
+			})
+		]
+	}
+};
--- a/test/apps/css/src/client.js
+++ b/test/apps/css/src/client.js
@@ -0,0 +1,9 @@
+import * as sapper from '../__sapper__/client.js';
+
+window.start = () => sapper.start({
+	target: document.querySelector('#sapper')
+});
+
+window.prefetchRoutes = () => sapper.prefetchRoutes();
+window.prefetch = href => sapper.prefetch(href);
+window.goto = href => sapper.goto(href);
--- a/test/apps/css/src/routes/_components/Title.html
+++ b/test/apps/css/src/routes/_components/Title.html
@@ -0,0 +1,7 @@
+<h1>Title</h1>
+
+<style>
+	h1 {
+		color: green;
+	}
+</style>
--- a/test/apps/css/src/routes/_error.html
+++ b/test/apps/css/src/routes/_error.html
@@ -0,0 +1,3 @@
+<h1>{status}</h1>
+
+<p>{error.message}</p>
--- a/test/apps/css/src/routes/bar.html
+++ b/test/apps/css/src/routes/bar.html
@@ -0,0 +1,11 @@
+<svelte:component this={Title}/>
+
+<script>
+	export default {
+		oncreate() {
+			import('./_components/Title.html').then(({ default: Title }) => {
+				this.set({ Title });
+			});
+		}
+	};
+</script>
--- a/test/apps/css/src/routes/foo.html
+++ b/test/apps/css/src/routes/foo.html
@@ -0,0 +1,7 @@
+<h1>Foo</h1>
+
+<style>
+	h1 {
+		color: blue;
+	}
+</style>
--- a/test/apps/css/src/routes/index.html
+++ b/test/apps/css/src/routes/index.html
@@ -0,0 +1,10 @@
+<h1>Great success!</h1>
+
+<a href="foo">foo</a>
+<a href="bar">bar</a>
+
+<style>
+	h1 {
+		color: red;
+	}
+</style>
--- a/test/apps/css/src/server.js
+++ b/test/apps/css/src/server.js
@@ -0,0 +1,8 @@
+import polka from 'polka';
+import * as sapper from '../__sapper__/server.js';
+
+const { PORT } = process.env;
+
+polka()
+	.use(sapper.middleware())
+	.listen(PORT);
--- a/test/apps/css/src/service-worker.js
+++ b/test/apps/css/src/service-worker.js
@@ -0,0 +1,82 @@
+import { timestamp, files, shell, routes } from '../__sapper__/service-worker.js';
+
+const ASSETS = `cache${timestamp}`;
+
+// `shell` is an array of all the files generated by webpack,
+// `files` is an array of everything in the `static` directory
+const to_cache = shell.concat(ASSETS);
+const cached = new Set(to_cache);
+
+self.addEventListener('install', event => {
+	event.waitUntil(
+		caches
+			.open(ASSETS)
+			.then(cache => cache.addAll(to_cache))
+			.then(() => {
+				self.skipWaiting();
+			})
+	);
+});
+
+self.addEventListener('activate', event => {
+	event.waitUntil(
+		caches.keys().then(async keys => {
+			// delete old caches
+			for (const key of keys) {
+				if (key !== ASSETS) await caches.delete(key);
+			}
+
+			self.clients.claim();
+		})
+	);
+});
+
+self.addEventListener('fetch', event => {
+	if (event.request.method !== 'GET') return;
+
+	const url = new URL(event.request.url);
+
+	// don't try to handle e.g. data: URIs
+	if (!url.protocol.startsWith('http')) return;
+
+	// ignore dev server requests
+	if (url.hostname === self.location.hostname && url.port !== self.location.port) return;
+
+	// always serve assets and webpack-generated files from cache
+	if (url.host === self.location.host && cached.has(url.pathname)) {
+		event.respondWith(caches.match(event.request));
+		return;
+	}
+
+	// for pages, you might want to serve a shell `index.html` file,
+	// which Sapper has generated for you. It's not right for every
+	// app, but if it's right for yours then uncomment this section
+	/*
+	if (url.origin === self.origin && routes.find(route => route.pattern.test(url.pathname))) {
+		event.respondWith(caches.match('/index.html'));
+		return;
+	}
+	*/
+
+	if (event.request.cache === 'only-if-cached') return;
+
+	// for everything else, try the network first, falling back to
+	// cache if the user is offline. (If the pages never change, you
+	// might prefer a cache-first approach to a network-first one.)
+	event.respondWith(
+		caches
+			.open(`offline${timestamp}`)
+			.then(async cache => {
+				try {
+					const response = await fetch(event.request);
+					cache.put(event.request, response.clone());
+					return response;
+				} catch(err) {
+					const response = await cache.match(event.request);
+					if (response) return response;
+
+					throw err;
+				}
+			})
+	);
+});
--- a/test/apps/css/src/template.html
+++ b/test/apps/css/src/template.html
@@ -0,0 +1,14 @@
+<!doctype html>
+<html lang="en">
+<head>
+	<meta charset='utf-8'>
+
+	%sapper.base%
+	%sapper.styles%
+	%sapper.head%
+</head>
+<body>
+	<div id='sapper'>%sapper.html%</div>
+	%sapper.scripts%
+</body>
+</html>
--- a/Show More
+++ b/Show More
				`@@ -0,0 +1 @@`
				`module.exports = require('../dist/rollup.js');`
				`@@ -0,0 +1 @@`
				`module.exports = require('../dist/webpack.js');`
				`@@ -0,0 +1 @@`
				throw new Error(`As of Sapper 0.22, you should not import 'sapper' directly. See https://sapper.svelte.technology/guide#0-21-to-0-22 for more information`);
				`@@ -0,0 +1 @@`
				`export { default as middleware } from './middleware/index';`