What API Development Actually Covers
“API work” spans two related jobs. The first is building your own API — the interface your web app, mobile app, or partners talk to, where design and documentation determine how easy everything downstream becomes. The second is integration: connecting to APIs you don't control — payment providers, CRMs, shipping, marketing tools — and making them work reliably despite their quirks, rate limits, and outages. We do both, and both live or die on the same things: clear contracts, real error handling, and security that isn't an afterthought.
What We Build
REST & GraphQL APIs.
Cleanly designed, versioned APIs your own front-ends and mobile apps consume — with the resource modelling that keeps them easy to extend later.
Third-party integrations.
Stripe, PayPal, HubSpot, Xero, shipping and marketing tools — connected with the retries, webhooks, and error handling that keep them running when the other side wobbles.
Security & rate limiting.
Authentication, authorisation, rate limiting, and input validation built in from the start — because an API is an attack surface, not just a convenience.
Webhooks & events.
Reliable webhook delivery and event handling — so systems react to each other in real time instead of polling and hoping.
What's Included in an API Project
A typical API engagement covers:
Need the full back-end, not just the API layer? See our Node.js development service.
Documented & Versioned — So It's Safe to Depend On
An undocumented API is a liability — every consumer becomes a support ticket, and every change risks breaking something silently. We build APIs that are documented, versioned, and predictable, so your own team and any partners can depend on them without a phone call.
The cost of a bad API isn't the API — it's every integration built on top of it, each one absorbing its quirks. We spend the design time up front so the tenth consumer is as easy to onboard as the first.
Ideal For
API DevelopmentWe've Actually Shipped
Live projects, real clients, and the full story behind each build — the problem, the decisions, and what changed afterwards.
How We Deliver — From First Call to Launch (and After)
No black box. Here's exactly what happens once you bring us in:
Discovery & scoping
A real conversation about the problem, the users, and the constraints — not a sales call. We leave it knowing exactly what needs building and why.
Fixed proposal & quote
You get a plain-English scope document, a timeline, and a fixed price. What's included, what's excluded, and what happens if scope changes — all in writing before any money moves.
Design & architecture
Wireframes, UI, and the technical architecture — database schema, API design, hosting — agreed up front so there are no expensive surprises mid-build.
Build in sprints
Development happens in short, reviewable cycles with a shared board. You see working software early and often, not a single black-box handoff at the end.
QA & testing
Every feature is tested — automated tests plus manual QA on real devices — before it's marked done. Nothing ships on a “works on my machine”.
Launch & handoff
Deployment, performance checks, and a walkthrough. You get the source code, the hosting, and the documentation — full ownership, zero lock-in.
Support & iteration
We stay on for bug fixes, monitoring, and new features on a retainer or ad-hoc basis — whichever fits how your product will actually grow.
How Much Does API Development Cost?
API development cost in the UK depends on scope and integrations. For reference:
| Option | Typical range |
|---|---|
| UK agency — custom API | £8,000 – £35,000 |
| UK agency — integration project | £5,000 – £25,000 |
| Freelance (variable quality) | £2,500 – £15,000 |
| API project via Codified Studio | from $900 |
The cheapest quote on paper isn't always the cheapest in practice — a low day rate that needs heavy management, or a build that needs redoing, costs more than a fixed scope delivered right the first time. With Codified Studio, pricing is transparent from the first quote: no hidden onboarding fees, no surprise scope creep, and full code ownership at the end. See the work we've delivered or tell us what you're building.
Get a Tailored QuoteFrequently Asked Questions
REST is the pragmatic default and perfect for most APIs. GraphQL earns its complexity when clients need to fetch very different shapes of data, or when a mobile app wants to avoid over-fetching over a slow connection. We'll recommend based on who's consuming the API and how, not on what's fashionable.
Yes — integration work is a big part of what we do. Whether it's Stripe, a CRM, shipping, accounting, or a marketing tool, we build the connection with the retries, webhook handling, and error handling that keep it reliable when the other service has a bad day.
Always. We generate OpenAPI/Swagger documentation and keep it in sync with the code, so your own developers, your mobile app, and any partners can build against it without guesswork or a support call.
Projects are priced in USD and invoiced via Payoneer or Elevate Pay — no international wire fees, no currency surprises. Fixed-price projects run 50% deposit to start, 50% on delivery, against a plain-English scope document agreed before any money changes hands.
100%. Source code, assets, hosting credentials, and domains are all transferred to you at handoff, with documentation. You're never locked into us for maintenance — everything is yours.
Both, chosen by fit rather than fashion: REST for straightforward resource APIs and public integrations, GraphQL where clients need to shape their own queries across a lot of related data. And yes — plenty of API work is extending or documenting something that already exists, including Laravel and other PHP back-ends. We don't require a rewrite to add a well-designed, versioned, documented API surface on top of what you run today.
Related Services
Would a dedicated developer suit you better?
A fixed-scope project works best when you know what you need built. If the work is ongoing, or you already have a team that just needs more capacity, embedding one of our developers full-time is usually the cheaper route.
Ready to start your api development project?
Tell us what you're building and we'll come back with a scoped recommendation and a fixed quote — not a generic sales call.