Self-hosted EPUB reader for calibre-web. No telemetry, no cloud, your data.
A self-hosted reading stack for people who already run calibre-web:
- Quire — native Android EPUB reader (Kotlin / Compose / Readium).
- Quire Server — small FastAPI service that stores reading progress
(and later bookmarks) in Postgres. Formerly named
opds-sync; the Python package is nowquire_serverand the container image isghcr.io/vitofico/quire-server(the legacyghcr.io/vitofico/opds-synctag is dual-published for one release cycle).
calibre-web stays the source of truth for books. Quire Server is the source of truth for reading state. Quire reconciles both on the device.
[calibre-web] ──OPDS + HTTP Basic──> [Android: Quire]
│
│ HTTPS + same Basic creds
▼
[quire-server]
│
▼
[Postgres]
The starting point was an OPDS catalog (calibre-web) and a simple need: read books from it on Android, with reading progress synced across devices.
That's harder than it sounds in the self-hosted world:
- KOReader has KOSync, but KOSync is shaped around KOReader's identity and document model. Using it as a generic sync layer for other clients means working against the grain.
- Stock OPDS readers on Android either don't sync reading position to a server you control, or sync it through a vendor cloud.
So Quire Server (originally shipped as opds-sync) is the piece that
was missing: a small, reader-agnostic progress server that speaks
OPDS-style document identity and uses your calibre-web account as
the only credential — no second IdP, no separate sync account. Quire
is the Android client built against it; nothing in the server design
is Quire-specific.
- No analytics, no crash reporting, no third-party SDKs.
- Network calls go to your calibre-web instance and your Quire Server. If your administrator has enabled AI features and you have opted in, Quire Server will additionally call the AI endpoint your administrator configured (such as a self-hosted Ollama, or a third-party provider you have chosen) and the public Wikipedia and OpenLibrary APIs to ground the generated insights. None of these AI-related calls happen unless you opt in from Quire's settings; the Android app itself talks only to your calibre-web instance and your Quire Server.
- Credentials are stored in Android Keystore (hardware-backed where the device supports it).
Quire optionally calls AI for book insights and library analysis. AI is off by default. The Quire Server admin enables it server-side by configuring an OpenAI-compatible endpoint (Ollama, llama.cpp, vLLM, OpenAI, OpenRouter, …); each user then opts in from Quire's settings.
When enabled, Quire Server sends the EPUB metadata (title, author, publisher, description, subjects) of books a user opens to the configured AI endpoint, plus deterministic queries to Wikipedia and OpenLibrary to ground the generated insights with citations. The generated insight is cached server-side per book and reused across all of that user's devices and other opted-in users on the same instance.
Surfaces in the app today: book-detail cards (summary, author, series,
themes, content advisory, sources); a catalog detail screen that
previews the same insight cards before download via an info icon on
each catalog tile; and a library Stats screen (totals, top authors,
top themes) backed by GET /library/v1/stats.
For configuration details see server/README.md.
Grab the latest APK from Releases, install it, and point it at your calibre-web URL on first launch. F-Droid listing is planned.
For the sync server, see server/README.md — it
ships two reference docker-compose files (docker-compose.yml for
"bring your own proxy"; docker-compose.full.yml for a Caddy-fronted
full stack with calibre-web + quire-server + TLS behind one base URL).
Shipped: OPDS catalog browsing and search, EPUB rendering with Readium, local reading progress, progress sync (server + Android client), single-credential auth via calibre-web Basic.
Planned: bookmarks sync, calibre-web read-only consumer plugin.
Not on the roadmap: PDF support (deferred), separate IdP or non-calibre-web auth.
This is pre-1.0 software built for the author's personal eink device. It works and it's tested, but the API and DB schema may still change. Pin a commit if you depend on it.
# Build the debug APK using the project's Docker-based Gradle wrapper.
# Host JDK and Android SDK are not required.
scripts/dgradle :app:assembleDebug
# APK at app/build/outputs/apk/debug/app-debug.apkSync server development:
cd server
uv venv && source .venv/bin/activate
uv pip install -e ".[dev]"
uv run pytest # spins up Postgres in Docker
QUIRE_SERVER_CWA_BASE_URL=https://library.example.com \
uv run uvicorn quire_server.main:app --reload # http://localhost:8000app/ Android entry point — Compose UI, navigation, DI wiring
auth/ Keystore-backed calibre-web Basic credential store
core/identity/ Document identity: hash + dc:identifier normalization
core/model/ Domain types (Document, Progress, Bookmark)
data/local/ Room database, DAOs
data/opds/ calibre-web OPDS client
data/sync/ quire-server REST client + WorkManager job
data/library/ quire-server /library/v1 HTTP client (stats today)
reader/ Readium navigator integration
server/ quire-server (Python / FastAPI; formerly opds-sync)
docs/ Architecture, development, sync API reference
scripts/dgradle Gradle wrapper that runs inside the project's Docker image
Dockerfile Reproducible Android build environment (linux/amd64)
docs/architecture.md— components, document identity, sync model, conflict resolution, auth.docs/development.md— module layout, build commands, testing, CI, releases.docs/sync-api.md— REST surface of Quire Server.
See CONTRIBUTING.md. TL;DR: gitmoji + conventional
commits, scripts/dgradle test and cd server && uv run pytest must
pass, no telemetry / analytics PRs.
If you find a vulnerability, please follow SECURITY.md
rather than opening a public issue.
Apache-2.0. See LICENSE and NOTICE.
If Quire is useful to you and you'd like to chip in, you can buy me a coffee:
