Own the appointment engine your business already runs on.
Custom Booking & Scheduling System Development
No-shows and double-bookings are the quiet cost of every appointment business. A generic Calendly plan hits its wall the day you need per-professional schedules, WhatsApp reminders in your voice, tenant isolation for multiple locations, or a payment link that keeps the money in your MercadoPago account. I build the booking system your business already runs on — as code you own, on infrastructure you control.
Why it matters
The moment your booking flow depends on a SaaS you rent, every future decision (a new professional, a new payment method, a change in the confirmation SMS) becomes a support ticket. When the platform lifts prices, changes limits, or deprecates an integration, the business has no answer. Owning the code closes that door.
What you get
- →Real-time bidirectional Google Calendar sync per professional, so bookings never collide with personal events.
- →WhatsApp Business Cloud API reminders (official — never Baileys or Evolution) in the tone the business already uses.
- →MercadoPago, Stripe or Payway subscriptions with plans, trial periods, MSI (meses sin intereses) and signed HMAC webhooks.
- →Multi-tenant architecture — one deployment serves 1 clinic or 400 clinics, each with isolated data.
- →PostgreSQL on a DigitalOcean droplet the client owns. No AWS lock-in, no Supabase surprise bills.
- →Cancellation slot reuse — a slot released 4 hours before is offered again automatically to the waitlist.
- →Encrypted patient / client data with role-based access, TOTP 2FA and full audit log.
- →WebSockets for live-slot updates on the booking page so two clients cannot claim the same slot.
Stack
- Next.js 14/15
- Node.js
- NestJS
- PostgreSQL
- Prisma
- WhatsApp Cloud API
- Google Calendar API
- MercadoPago
- Stripe
- Socket.io
- Docker
- DigitalOcean
Delivered projects using this stack
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 questions
How long does a production-ready custom booking system take?+
The MVP (calendar, booking flow, WhatsApp reminders, one payment integration, one admin panel) ships in 3–4 weeks. Multi-tenant, subscription plans, waitlist and cancellation logic add another 2–3 weeks. Everything is delivered as code the client owns, deployed to their own DigitalOcean droplet.
Why not use Calendly, Cal.com, Acuity or SimplyBook?+
For a single professional they are fine. For a business with 3+ practitioners, custom reminder templates, split payments to different accounts, insurance-specific flows, or a bilingual patient experience, the SaaS ceiling comes fast. Every workaround becomes a maintenance debt. Owning the code costs slightly more upfront and pays back inside 8–12 months by removing every per-user fee.
Can WhatsApp reminders send automatically without paying per message?+
They use WhatsApp Business Cloud API official (via a Business Solution Provider), which is what Meta requires for automated flows. The per-conversation cost is Meta official pricing — much lower than any third-party BSP markup, and there is no per-contact SaaS fee on top.
What happens when the booking system is live?+
A 60-day warranty covers any behavioral defect free of charge. After that, ongoing maintenance is optional and charged per hour actually worked, not a subscription. Most clients stay in touch for evolution (new features, new payment methods, new integrations), not for keep-it-running work.
Where does the code and the data live?+
On a DigitalOcean droplet in the client's own account. PostgreSQL runs on the same droplet as the application (never a separate Supabase / RDS instance). The GitHub repository is transferred to the client's organization at delivery.
Ready to start?
Send a written brief with the business problem to solve. I come back with a concrete plan against that document, in the client's language.
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