Booking System Developer
Hire a developer to build your booking system
The booking engine your business actually runs on — owned outright, not rented per seat. Real-time calendar sync, WhatsApp reminders in your voice, payments into your own account, and a cancellation queue that refills the slot before the front desk even notices.
The part most people get wrong
No-shows and unfilled cancellations are the two invisible leaks in every appointment business. Measured across three pilot clinics: WhatsApp reminders cut no-shows from 18% to 8%, and an automatic waitlist offer refilled 22% of cancelled slots the same day. That is pure margin nobody was capturing.
What you get
- →Real-time bidirectional Google Calendar sync per professional via push notifications, not polling — bookings appear in under 2 seconds and personal events block slots automatically.
- →WhatsApp Business Cloud API reminders at 24h and 2h, as a conversation (reply 1 to confirm, 2 to cancel) not a broadcast.
- →Cancellation slot-reuse queue that offers the freed slot to the waitlist with a 15-minute claim window, cascading automatically.
- →Postgres advisory locks on slot claims so two patients clicking 200ms apart cannot both win.
- →WebSockets for live availability so the picker updates the instant a slot is taken.
- →MercadoPago, Stripe or Payway subscriptions with plans, trials and MSI.
- →Multi-tenant from day one — one deployment serves 1 clinic or 400 with isolated data.
- →Encrypted patient records with RBAC, TOTP 2FA and a full audit log.
Proof — shipped and in production
ArTicket Platform
A ticketing operator was renting its platform. The own 2D canvas seat-map engine runs at 39fps on 10k+ seats, and the operator owns it now.
Sensu Angela
Elderly SOS pendants used to call the family. Now they ping a 24/7 call center and every family member in real time, live on iOS and Android.
IF7Sports Platform
Sports centres could not share courts across a reseller network without double-booking. Atomic tenant-isolated booking with commission accounting handles it.
Agendux
No-shows are the quiet cost of every appointment business. Reminders reach clients on WhatsApp, and a cancelled slot gets offered again.
Frequently asked
Why build instead of paying for Calendly or Acuity?+
For a single professional, do not build — use the SaaS. Build when you have 3+ practitioners, need custom reminder templates, split payments to different accounts, insurance-specific flows, or a bilingual patient experience. At that point every SaaS workaround becomes maintenance debt, and ownership pays back in 8-12 months by eliminating per-user fees.
How long until it is live?+
The MVP — calendar, booking flow, WhatsApp reminders, one payment integration, admin panel — ships in 3-4 weeks. Multi-tenant, subscription plans, waitlist and cancellation logic add 2-3 more.
Does it integrate with the calendar the team already uses?+
Google Calendar, bidirectionally and in real time. Outlook/Microsoft 365 is also supported. The professionals keep the calendar they already live in; the booking system just stops colliding with it.
This role is also called
- appointment software developer
- scheduling system engineer
- reservation system developer
- calendar integration developer
Start with a written brief
Describe what the business is losing today and what the target outcome looks like. I come back with a concrete plan against that document — in English, Spanish, Portuguese or Polish.
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