Chidi Okonkwo
Web Application Development
Next.js MVP build — from figma to deployed in three weeks
Works with TypeScript, PostgreSQL
from$1,200.00
Availability, buffers, time zones and no double bookings, ever.
Developers who work with TypeScript, NestJS, PostgreSQL and take scoped work with a fixed price and delivery date.
Web Application Development
Works with TypeScript, PostgreSQL
The scheduling problem, solved properly: availability rules with buffers and lead times, correct time-zone handling including the twice-yearly transitions that break naive implementations, atomic booking with a database-level exclusion constraint that makes a double booking impossible rather than unlikely, and calendar sync both ways.
Double booking is impossible
A PostgreSQL exclusion constraint over the time range. Not a check in application code.
Time zones done right
Including the DST transitions where an hour happens twice or not at all.
Two-way calendar sync
Google, Microsoft and CalDAV, with conflict rules that are written down.
Buffers and lead times
Per-service, per-resource, and they compose.
4.4
8 reviews
8 verified
Consulting
Works with PostgreSQL
API Integration
Works with TypeScript
Source Code
Rider assignment, route batching and proof of delivery for small logistics operations.
Developer Tool
Refresh-token rotation with reuse detection, TOTP, WebAuthn and a device list.
Source Code
Auth, organisations, seats, Stripe billing and a migration path. Deploy this afternoon.
API
Issue, send, chase and reconcile invoices over a clean REST API.
Solid code and clear structure. The setup guide assumes you already have Docker working, which cost me an hour.
22 found this helpful
Nothing abandoned, nothing pinned to a version that was withdrawn. I audited the tree before buying and it held up.
5 found this helpful
Seller replied
Fresh database, one command, working schema. I have been burned enough times to be impressed by that.
20 found this helpful
The code is good. The README skips two required environment variables and I had to read the source to find them.
4 found this helpful
Seller replied
I actually enjoyed reading this codebase, which is not something I say often.
28 found this helpful
Seller replied