calit — self-hosted Calendly alternative

calit is a self-hosted, multi-user scheduling app — a Calendly alternative built on Quarkus. Every user runs their own independent scheduling page at /<username>/<slug>: isolated meeting types, availability, bookings, settings, and Google account. Invitees pick a slot and book; bookings optionally sync to Google Calendar (auto Meet link) and email both parties. Pages are server-rendered with no runtime JavaScript required, and it runs as N stateless replicas behind a load balancer with all shared state in Postgres.

Features: per-type buffers, min-notice / booking-horizon, date-specific availability overrides, an approval workflow, custom booking-form fields, reminder emails, multi-user tenancy with per-user owner-scoping (argon2id passwords), site-admin user management, optional Google Calendar sync, optional OIDC / SSO login, and public-form abuse protection (Cloudflare Turnstile or self-hosted ALTCHA, plus honeypot + per-email daily cap), and GDPR tooling (invitee data download and erasure, account export and deletion, an optional retention window, a privacy policy that describes the running deployment). UI localised to en / de / he.

📖 Documentation

Full docs — install, configuration, reverse-proxy, Google / Turnstile / ALTCHA / OIDC setup, usage, and changelog — live at https://asm0dey.github.io/calit/. This README is intentionally short; the site is the source of truth.

Screenshots

Public landing	Booking page

Owner dashboard	Booking confirmation

Requirements

• PostgreSQL — the only supported database. No embedded fallback.
• An SMTP server — required, not optional. calit's core promise to an invitee is "you'll get a confirmation," and every booking confirmation, reminder, approval request, cancellation notice, password reset, and account invite goes out over SMTP. Without working SMTP the app still runs and bookings still succeed — that's exactly what makes it dangerous: the booking flow looks fine from the guest's side while not one of them receives anything. Configure MAIL_* (see .env.example and the full docs); a failed send isn't a lost mail — it's parked in a durable outbox and retried with backoff. The owner dashboard shows a banner whenever mail isn't being delivered, along with a count of messages that were never delivered and are no longer being retried; /q/health/ready reports SMTP reachability under the SMTP check's data.state.
• Docker — only for development (mvn quarkus:dev and the test suite use Dev Services to provision a throwaway Postgres). Not needed to run a release image.

Run it

Prebuilt multi-arch images are published to ghcr.io/asm0dey/calit and, with identical tags, docker.io/asm0dey/calit (tags: latest, 1.27.1, 1.27.1-native). The fastest path is Docker Compose:

cp .env.example .env    # set at least DB_PASSWORD, SESSION_ENCRYPTION_KEY, APP_BASE_URL, MAIL_*
docker compose up -d    # pulls the image; Flyway migrates on boot

Privacy knobs, all optional: INVITEE_ERASURE (default true: invitee self-service erasure on the manage link), BOOKING_RETENTION_DAYS (unset = keep bookings forever; otherwise anonymise them that many days after they end), and PRIVACY_POLICY_PATH / TERMS_PATH (an HTML fragment replacing the shipped /privacy / /terms body). See the GDPR operator guide.

Full self-hosting instructions (compose file, required/optional env vars, reverse proxy, scaling, upgrade notes) → Installation docs.

Develop

Prereqs: JDK 27 (build; the app targets Java 25), Bun (CSS), and Docker (Dev Services provisions a throwaway Postgres + mock mailer for dev and tests).

bun install            # once — installs the Tailwind/daisyUI CLI + wires the lefthook pre-commit hook
bun run css:watch &    # compiles src/main/css/input.css -> /calit.css (gitignored; build once)
mvn quarkus:dev        # dev server at http://localhost:8080  (Docker must be running)
mvn test               # full suite (Docker required)

On a fresh database, any page redirects to /setup to create the first (admin) user — there is no default password. See CONTRIBUTING.md for the full contributor guide (testing, formatting, i18n, migrations, docs).

License

Licensed under the GNU Affero General Public License v3.0 (AGPL-3.0) — see LICENSE. If you run a modified version as a network service, you must offer its complete source to that service's users.

"Calendly" is a trademark of Calendly LLC. calit is an independent, self-hosted project not affiliated with, endorsed by, or sponsored by Calendly; the name is used only descriptively.