API Development Services

Your frontend needs a backend it can rely on. But right now, you might have a prototype endpoint that breaks under load. Or a Zapier chain that fails silently when a third-party API changes.

Client applications end up guessing the request schema. Background tasks choke the main thread. Partner integrations break because webhook signatures were never verified properly. You hire an agency, they hand over an outdated Swagger file, and then they disappear.

I build production-ready REST APIs and third-party integrations. You get typed endpoints, background workers, and auto-generated documentation. One developer owns the architecture, implementation, and deployment. You talk directly to the person writing the code.

The quick numbers: API and integration projects typically run $1,500 to $10,000+. Most ship in 2 to 6 weeks depending on scope. A focused REST API or single third-party integration lands faster. Multi-service backends with workers and webhooks take longer.

What I build

If you need a full product UI alongside your backend, look at my web application development service. Still validating a core idea? Start with MVP development.

The deliverables

Technology stack

I pick tools that fit your product and your team.

• Backend: Python (FastAPI, Django), Node, Go
• Data: PostgreSQL, Redis, standard object storage
• Workers: Celery, RQ, or cloud queue workers for asynchronous jobs

The default choice: FastAPI paired with Postgres and Redis. I use this when async work and high performance are required.

If you already run a backend, I extend it. Greenfield APIs get a stack chosen for maintainability and hiring speed, not novelty.

How we work together

1. Discovery: We figure out what systems need to talk, who consumes the API, and what “done” looks like. Email me or book a 30-min call.
2. Written scope: You get a document defining endpoints, integrations, milestones, and a fixed quote.
3. Build and ship: I implement, test, deploy, and document the system.
4. Handover: You get full repository access, runbooks, and optional follow-on support.

I quote fixed-price, fixed-scope for defined builds. Open-ended retainers are available for ongoing backend work after the initial release.

Recent API projects

I am Ekky Armandi, a self-taught software engineer with 5+ years of client delivery. You can verify my track record on my Upwork profile.

Some recent backend work:

• Uninote: A FastAPI backend featuring auth, Stripe subscriptions, and AI pipeline endpoints.
• OpsGuide: A multi-tenant workflow automation platform heavily reliant on integration hooks.
• Trade Arena: An algorithmic trading dashboard wired directly to the client’s execution engine via a custom API layer.
• Flaz: An OCR and AI extraction API that feeds structured data to a React canvas frontend.

See more in my portfolio.

Is this a fit?

This is a good fit if:

• You need a production REST API for a web or mobile frontend.
• Your third-party integrations are breaking or outgrowing no-code tools.
• You want OpenAPI documentation and typed contracts for partner or internal teams.
• You need webhooks, sync jobs, or a backend refactor without the overhead of hiring an agency.

This is not a fit if:

• You haven’t validated the product idea yet. My MVP development service is the better entry point.
• You need a simple one-step Zap with no custom logic. No-code tools are likely enough.
• You want a microservices architecture on day one without a concrete scaling problem forcing that decision.

Start the process

1. Email me with what the API should do, what systems it connects to, and any deadline pressure.
2. Or book a call to talk through the requirements live.

I reply within 1 to 5 business days with an honest assessment. If no-code or a smaller MVP sprint makes more sense, I will tell you.

Where to go next

• Web application development: Build full web applications including both frontend and backend systems.
• MVP development services: Scope and build an early-stage product to validate your core idea.
• AI system and integration services: Deploy RAG pipelines, agents, and AI features into your production environment.
• Modern REST API development for startups: Read about the architecture and stack choices that keep early-stage backends fast.
• Custom API development vs no-code integration: Learn when you should write custom code versus buying a no-code solution.

FAQ

How is this different from your web application service?

Web application development includes UI, product flows, and deployment end to end. API development is scoped specifically for when the backend, external integrations, or public API surface is the primary deliverable.

Do I own the code?

Yes. It lives in your repository. You own the intellectual property and get documented handover.

Can you fix or extend our existing API?

Yes. I regularly harden, document, and extend existing FastAPI, Django, and Node backends.

What about GraphQL or gRPC?

REST is the default for most startup web and mobile products. If your client team or external partners specifically require GraphQL or gRPC, we scope that explicitly during discovery.

How long does API development take?

Expect 2 to 6 weeks for most engagements. A single integration or small REST surface can ship in 2 weeks. Multi-service backends with workers and webhooks typically need 4 to 6 weeks.