API Development and Service Integration in TypeScript/Node.js by Sofwan Lawal

API Development and Service Integration in TypeScript/Node.js

Sofwan Lawal

Contact for pricing

About this service

Summary

Build reliable, scalable APIs with clean architecture and seamless integrations. With over 9 years of backend experience, I help startups and growing teams design and implement RESTful and GraphQL APIs in TypeScript using Node.js (Express, NestJS, or custom stacks).

Whether you need a new API built from scratch, an existing one refactored, or third-party services integrated (Stripe, Twilio, Firebase, etc.), I deliver production-ready solutions with performance, testability, and maintainability in mind.

You’ll get a well-documented, versioned, and future-proof API your frontend and partner teams will love working with.

Process

Requirement Gathering We define your API scope, data models, expected integrations, and edge cases.

Design & Planning I prepare the API spec, architecture decisions, and dependencies before writing any code.

Development I build your API using TypeScript best practices — modular structure, validations, error handling, and tests included.

Service Integration External APIs or internal services are connected using secure, abstracted, and testable modules.

Documentation & Handoff I deliver your API with full documentation and dev instructions. Optional post-delivery support included.

FAQs

What frameworks do you use?
Elysia.js for flexibility, NestJS for structure-heavy projects. I can also work with custom or minimal stacks if needed.
Can you connect my API to my database?
Yes. I work with PostgreSQL, MySQL, MongoDB, and Redis. I can set up the schema, models, and migrations using ORM or raw SQL.
Can you help refactor an existing API?
Absolutely. I can step in to clean up architecture, modularise logic, improve error handling, or boost performance.
Do you write GraphQL APIs?
Yes — using tools like Apollo Server and TypeGraphQL. Let me know if you're going GraphQL-first.
Can you deploy the API for me?
Deployment to platforms like AWS, Render, Railway, or DigitalOcean is available as an add-on.
Do you offer ongoing API support?
Yes. I offer monthly retainer options for continuous API maintenance, feature extension, and integration work.

What's included

API Design Blueprint
API spec with routes, methods, request/response structures, and error handling. Shared via Swagger/OpenAPI or Postman collection.
Fully Functional API (REST or GraphQL)
A complete API built in TypeScript using Node.js frameworks (Express, NestJS, or custom), including validation, middleware, and structured modules.
Third-party Service Integration
Integration with external APIs or services (e.g., Stripe, Firebase, SendGrid, AWS, etc.) with proper abstraction.
Unit & Integration Tests
Tests for routes, controllers, and core logic to ensure stability and catch regressions early.
Environment Configs & Dev Scripts
Ready-to-run dev setup with .env configuration, seed scripts, and clear documentation.
API Documentation
Developer-friendly API docs for internal or external usage, generated automatically or manually written.
Post-Delivery Support (2 Weeks)
I’ll be available for questions or minor adjustments after delivery to ensure a smooth handoff.