BookingBot - Bilingual Appointment SaaS - Sell Project

The one thing genuinely hard to build in a booking system is guaranteeing two customers can never grab the same slot. BookingBot enforces this at the database level with a Postgres EXCLUDE constraint spanning appointment time plus buffer, not application code that can race. This was mutation-tested under real concurrent load. Built for reselling to small businesses: salons, clinics, studios. Single business per install, fully self-hosted, source included. What's included: Public booking flow with real-time availability, staff selection, and buffers Owner dashboard: calendar, staff, services, working hours, time off, CSV export Stripe deposits (hosted Checkout, no card data touches this codebase) Email confirmations, reminders, and cancellation notices Google Calendar sync (create/remove events, scoped to calendar.events only) Bilingual EN/RU throughout, switchable per page Optional Claude-powered booking assistant and daily briefing Tech stack: FastAPI + PostgreSQL backend, React + TypeScript frontend, Docker Compose deployment, GitHub Actions CI (85 pytest, 41 browser checks, and a real docker compose up on every push). Hardened against real attacks before release: rate-limit bypass via forged headers, calendar-hoarding scripts, HTML/CSV injection, and more. Full writeup in the README. Licence: one business per purchase, modify freely, keep changes private. Not for resale as source or as a hosted multi-tenant service. Live demo linked below — book a real slot and see the admin dashboard yourself.