FlexiBer
A German nursing consultancy ran bookings by phone, email, and paper — no online flow, no overview, and no off-the-shelf tool that fit a regulated, GDPR-bound workflow.
// THE PROBLEM
The consultancy booked appointments over the phone and by email: double-bookings, no shared overview, and hours lost to admin. Generic booking SaaS either didn't model the consultancy's workflow or couldn't satisfy German data-protection requirements. They needed an owned, EU-hosted system — public booking on one side, a live admin cockpit on the other. I built FlexiBer to be that system end to end.
// WHAT I BUILT
Public, multi-language booking flow (DE/EN/ES) with a deterministic availability engine — opening hours, exceptions, lead time, and buffers, all computed in Europe/Berlin so DST never breaks a slot.
Realtime admin cockpit — new bookings, status changes, and contact messages appear live, with a week calendar, inbox, and a Tiptap reply editor.
Automatic patient matching: every booking links to a profile via an insurance-number → email → phone+name cascade, with diacritic- and format-aware normalization and duplicate flagging.
Locale-aware transactional email rendered from React components to HTML and plaintext, plus per-booking Jitsi video rooms minted with signed moderator tokens.
GDPR by construction — self-hosted in the EU, argon2id auth, full audit log, rate-limited booking endpoint, no third-party fonts or analytics at runtime.
// THE INTERESTING PART
The admin cockpit updates in real time with no polling and no websocket infrastructure — Postgres is the message broker. A booking commit calls pg_notify on an admin_events channel; each admin tab holds an SSE stream whose handler LISTENs on that channel and forwards the JSON payload straight to the browser, with a 25-second heartbeat and clean teardown on disconnect. No Socket.io, no Redis, no separate realtime service — the database that already owns the truth also delivers the updates.
// IN THE PRODUCT
// OUTCOME
Live in production for the consultancy, handling roughly 80 bookings a week across multiple consultants — public booking, patient matching, video consultations, and a realtime admin cockpit, fully self-hosted in the EU.