Sami Ullah is a NestJS developer based in Pakistan who builds structured, typed REST APIs. His NestJS work covers JWT authentication, role-based guards, validation pipes, PostgreSQL data models and background jobs, and powers booking systems with SMS reminders sent through his own SimRelay gateway.
Used professionally since 2025 (1+ years)
NestJS is my default for APIs that have business rules worth protecting: who can book which slot, who can see which record. Modules keep features separate, guards keep authorisation in one place, and pipes reject bad input before it reaches a service.
I pair NestJS with PostgreSQL and use database constraints, not only application code, to stop problems such as double bookings.
Official documentation: NestJS documentation
Own product
A system I built that calls a list of consented contacts with an AI voice agent, holds a short qualifying conversation and records every result as a tracked outcome or lead. A NestJS API runs the dialing, compliance checks and webhooks, and a Next.js dashboard with a built-in AI assistant lets the owner run campaigns and ask for reports in plain language.
Own product
A multi-salon booking marketplace I designed and built for Pakistan. Clients find nearby salons on a map, choose a barber, service and time, and book at the salon or as a home visit. Salons run staff, schedules and earnings from their own dashboard, and the platform collects a commission per completed booking through daily settlements.
#nestjs6 min
A practical guide to API versioning in NestJS 11: URI, header and media type strategies, version-neutral routes, deprecation headers and when to bump.
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#postgresql6 min
How to prevent double booking in PostgreSQL: a booking schema with tstzrange, a btree_gist exclusion constraint, and clean 23P01 handling in NestJS.
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#nestjs6 min
How to build NestJS JWT refresh tokens properly: short-lived access tokens, rotated refresh tokens stored as hashes, httpOnly cookies and reuse detection.
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Sami Ullah is a full stack developer based in Sargodha, Pakistan, who builds NestJS APIs with PostgreSQL and works remotely with international clients. His NestJS work includes authentication with JWT and refresh tokens, role-based guards, validation pipes, background jobs and booking logic.
A typical API includes feature modules, DTOs validated with class-validator through a global ValidationPipe, JWT authentication with refresh tokens, role-based guards, consistent error responses from an exception filter, OpenAPI docs generated with Swagger, and database migrations so every environment has the same schema.
Both work. Prisma gives a typed client generated from one schema file and clear migrations, which suits most new projects. TypeORM fits teams already using decorators and entities. The choice depends on the existing codebase; for a new NestJS and PostgreSQL project he usually starts with Prisma.