Chek

Just one more chapter.
A reader for your books and comics, on iPhone and iPad.

Get it on the App Store · Website · Contributor guide · Report a problem

This repository holds the native Chek apps, starting with iPhone and iPad, and Chek on the web. Chek 2.0 is live on the App Store.

What the app does

• Your own files. Add EPUB, PDF, CBZ and CBT comics, MOBI, AZW3, FictionBook, plain text and Markdown from Files. Each one opens where you left it, offline and without an account.
• Your own server. Connect a Chek server to read its libraries and the sources its extensions add. Follow a series to hear about new chapters, and download chapters to read offline.
• A demo to try. Try the Demo, from Settings or an empty screen, connects to demo.chek.page until the app is closed.

Books are read with Chek Reader, the reading engine Chek maintains as a standalone Swift package. The server is a separate project, and the app never needs it.

Requirements

• Xcode 27 and Swift 6.4 to build.
• Runs on iOS and iPadOS 26 or later.

Development

You can work without a phone, in the iOS Simulator:

open apple/Chek.xcodeproj

Or from the command line:

xcodebuild build -project apple/Chek.xcodeproj -scheme Chek \
  -destination 'generic/platform=iOS Simulator' CODE_SIGNING_ALLOWED=NO

The unit tests run on an iPhone simulator:

xcodebuild test -project apple/Chek.xcodeproj -scheme Chek \
  -destination 'platform=iOS Simulator,name=iPhone 18 Pro' CODE_SIGNING_ALLOWED=NO

Chek Reader

Chek Reader comes through Swift Package Manager, pinned to a release (0.1.0 up to the next minor), so a build is the same today and next month.

• Take a new release. Raise the version in the project's package dependency, then let File → Packages → Update to Latest Package Versions rewrite Package.resolved.
• Try unreleased changes. Add the package locally with File → Add Package Dependencies → Add Local. It overrides the pinned one until you remove it.

The web app

web/ is Chek on the web, served at app.chek.page. It has three parts so far:

• The reading app, on par with the iOS app. You sign in to one or more Chek servers, and stay signed in until you sign out. It reads comics, EPUB, PDF, plain text and Markdown with Chek Reader, browses shared libraries and sites, and installs as an app that opens offline. The code is in src/app.
• Content settings, where adults turn on mature series. The iOS app doesn't offer that, so it opens this page in Safari, signed in with a one-time code from the server.
• The admin panel at /admin, where a server's admins set it up with its setup token, then manage libraries and their scans, people and the libraries each one reads, extension repositories and settings.

The server image bundles the whole app, built with bun run build:server, at http://<server>:8080/, with the admin panel at /admin, since an https page can't reach a server on plain http. app.chek.page reaches servers with https addresses.

• Stack. SolidJS with TanStack Router, built with Vite and run with Bun.
• Look. It follows the app and chek.page: Tailwind CSS with the brand's colors and fonts in src/styles.css, and shadcn-style components from solid-ui, built on Kobalte, in src/components/ui.

cd web
bun install
bun run dev        # http://localhost:18358
bun run typecheck && bun run lint && bun run format:check && bun run build
bun run build:server   # the app the server serves, in dist-server/

• Deploy. Every push to main that changes web/ publishes it to Cloudflare at app.chek.page through the Deploy web app workflow, which signs in with the CLOUDFLARE_API_TOKEN repository secret. To redeploy without a push, run the workflow from the Actions tab. From your own machine, bun run deploy builds and publishes it after cf auth login.
• Local server. A server accepts calls from the origins in CHEK_WEB_ORIGINS (https://app.chek.page by default). To use a local server with the dev page, start it with CHEK_WEB_ORIGINS=http://localhost:18358. Once the page is served over https, it reaches only https servers.

Repository layout

apple/
  Chek.xcodeproj/   The app project
  Chek/             App sources
    App/            Entry point, routing and the root tabs
    Home/           Reading Now: what you're reading, following and what's new
    Library/        The on-device library: import, storage, covers and the grid
    Reader/         The reading screen around Chek Reader
    Servers/        Chek servers: connecting, browsing, syncing positions
    Sources/        A server's sources: browsing, following, downloads
    Search/         Searching everything at once
    Settings/       Settings and storage
    Model/          SwiftData models and their schema versions
    Components/     Views and image loading shared across screens
  ChekTests/        Unit tests
web/                Chek on the web, at app.chek.page
docs/               Architecture notes
.github/workflows/  CI

See AGENTS.md for the conventions contributors and coding agents follow.

License

The Chek apps are licensed under the GNU Affero General Public License v3.0. The fonts in web/src/fonts keep their own SIL Open Font License, next to each font.