SERVICE 03
API Development Services
REST API development and backend integrations for startups. Typed endpoints, OpenAPI docs, webhooks, and third-party API wiring. One developer, fixed scope, production-ready delivery.
See pricing
Typical project range
2 to 6 weeks
Typical delivery window
1 developer
You talk to who builds it
00 / OVERVIEW
Why this service exists
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 You hire an agency, they hand over an outdated Swagger file, and then they disappear.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.
01 / SCOPE
What I build
REST APIs
CRUD backends, partner-facing APIs, mobile app backends
Third-party integrations
Stripe, CRMs, payment rails, shipping providers, legacy systems
Webhooks
Idempotent handlers, retries, signature verification
Background jobs
Email dispatch, data exports, async sync tasks
API hardening
Auth, rate limits, versioning, strict error contracts
Documentation
OpenAPI and Swagger generated directly from the codebase
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.
02 / DELIVERABLES
The deliverables
01
Written scope
Defined endpoints, integrations, timeline, and a fixed price before any code is written
02
Typed API layer
Strict request and response schemas so client developers don't have to guess
03
OpenAPI docs
Live Swagger UI that stays perfectly synced with the code
04
Auth and security
JWT, API keys, OAuth flows, and proper webhook verification
05
Deployment
Railway, AWS, Vercel functions, or your existing cloud environment
06
Handover
Source code in your repository, setup documentation, and a technical walkthrough
03 / STACK
Technology stack
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 is FastAPI paired with Postgres and Redis, used 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.
04 / PROCESS
How we work together
01
Discovery
We figure out what systems need to talk, who consumes the API, and what done looks like. Email me or book a 20-min call.
02
Written scope
You get a document defining endpoints, integrations, milestones, and a fixed quote.
03
Build and ship
I implement, test, deploy, and document the system.
04
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.
05 / PROOF
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.
A FastAPI backend featuring auth, Stripe subscriptions, and AI pipeline endpoints.
A multi-tenant workflow automation platform heavily reliant on integration hooks.
An algorithmic trading dashboard wired directly to the client's execution engine via a custom API layer.
An OCR and AI extraction API that feeds structured data to a React canvas frontend.
See more in my portfolio.
06 / FIT
Is this a fit?
GOOD FIT
- 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.
NOT A FIT
- 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.
07 / FAQ
FAQ
01
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.
02
Do I own the code?
Yes. It lives in your repository. You own the intellectual property and get documented handover.
03
Can you fix or extend our existing API?
Yes. I regularly harden, document, and extend existing FastAPI, Django, and Node backends.
04
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.
05
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.
Ready to scope
Ready to scope an API or integration? Tell me what you need built.
mail@ekky.dev with what the API should do, or book a 20-min discovery call to check fit and ballpark direction.