Chara

Chara is a mobile-native bill-splitting app — iOS, Android, and Web from one codebase — backed by a small Go API you can run yourself. It's a direct alternative to Splitwise and Steven, with one fundamental difference: it's fully open source under AGPLv3, and your data stays on your server.

A hosted option (Chara Cloud) exists as an optional, paid convenience that funds development. It runs the exact same code in this repository.

• Splitwise has paywalled core features (receipt scanning, search, charts, and capped free-tier expenses) behind a subscription.
• Steven, the Nordic incumbent, is in operational decline.
• Existing open-source alternatives are web-only PWAs or single-platform — none offer native iOS and Android and true self-hosting and Nordic payment-rail integration (Swish, Vipps, MobilePay).

Chara fills that gap.

That third-to-last row is the one nothing else does: link your own server and a friend's server in the same app, and see both sets of balances side by side.

• Groups & expenses — split equally, by share, by exact amount, or by percentage.
• Multi-currency — per-expense currency with FX snapshotting; balances never sum across currencies.
• Balances & settlement — net standings per person with debt simplification.
• Multi-server accounts — hold N independent server-accounts in one app and aggregate them into a single UI. Self-host your own and link a friend's server side by side.
• Receipt scanning — optional AI-assisted line-item extraction.
• Auth that fits the deployment — magic link everywhere; Google / Apple Sign-In on the hosted tier. OIDC (Authentik, Keycloak, Authelia, ...) for self-hosted instances is planned.
• Push notifications, internationalization, and a privacy-respecting design.

Chara is shipping on the App Store and Google Play and is under active development. See docs/implementation-status.md for what's built today and docs/06-roadmap.md for what's next.

One machine with Docker (x86 or ARM — a Raspberry Pi is fine) and ~10 minutes:

git clone https://github.com/DowLucas/chara.git
cd chara/deploy
./setup.sh

The script asks three questions, generates every secret, starts the API + Postgres + MinIO from the published ghcr.io/dowlucas/chara-backend image (optionally with Caddy for automatic HTTPS), and prints the address to type into the app under use my server →. Full walkthrough, manual setup, updates and backups: deploy/README.md.

• Backend (Go): backend/README.md. The repo-root ./run-backend script idempotently brings up Postgres, the API, and MinIO.
• App (Expo): app/README.md.

Contributions are welcome — bug reports, features, docs, and translations. Please read CONTRIBUTING.md first; it covers the TDD workflow, the minimum-diff philosophy, the i18n rules, and the money-as-integer-minor-units invariant. By participating you agree to the Code of Conduct.

Good places to start: issues labelled good first issue, and translations — every locale lives in a single JSON file under app/lib/locales/ (15 languages today).

If Chara is useful to you, a ⭐ on the repo genuinely helps other people find it.

Found a vulnerability? Please report it privately — see SECURITY.md. Do not open a public issue for security problems.

Chara is licensed under the GNU Affero General Public License v3.0. See LICENSE. The AGPL's network-use clause means that if you run a modified Chara as a network service, you must offer your users the source of that modified version.