Backend
Hire Node.js Developers
Node engineers who run services in production and have been on call for the ones they wrote.
Node earns its place where a service is mostly waiting — on a database, a payment gateway, a device, another API — and where sharing types with the front end removes a whole class of integration bugs. Sazinga Comply runs on Fastify with Postgres, Rentals on Express and Sequelize, Factory on Node and TypeScript alongside Angular, so the operational lessons here are first-hand rather than borrowed.
When hiring, ask about failure. What happened the last time a queue backed up, how they found a memory leak, what their retry policy did to a downstream system. Engineers who have only built endpoints will describe frameworks. Engineers who have kept a service alive will describe backpressure, idempotency keys and the dashboard they wished they had built earlier.
What these engineers do
- Express, Fastify and NestJS services in TypeScript with typed request contracts
- PostgreSQL access via Prisma, Sequelize or plain SQL, with migrations under review
- Queues and background jobs in BullMQ, with idempotency and retry semantics designed
- Structured logging, OpenTelemetry tracing and alerting that maps to real failure modes
- Diagnosing event loop lag, memory growth and slow queries in a running system
Delivered AI-first
AI assistance is used to generate route handlers from an OpenAPI or schema definition, to write validation layers, repository code and integration tests, and to carry out framework migrations such as Express to Fastify one route at a time. Anything touching authentication, database transactions or money is written and reviewed with the same care as before. Review discipline is unchanged. The measurable effect is throughput per engineer, not fewer reviews.
Built with Node.js at Sazinga
These are our own production applications, not client references — which is why the engineers have operated them, not just written them.