API Development and Integration
Custom APIs and third-party integrations that connect the systems your business runs on
What this actually involves
An API is the connection that lets two pieces of software talk to each other: your website pulling stock levels from a warehouse system, a checkout handing a payment to Stripe, a booking form writing into your CRM. We build those connections, and we build the APIs that other systems connect to. A lot of full-stack work is this plumbing — rarely seen, but it's what breaks everything when it's wrong.
Building an API
If you need to expose your own data — to a mobile app, a separate frontend, or a partner who'll consume it — the API has to be designed for that from the start. We build REST and GraphQL APIs in Node.js and TypeScript, with authentication, rate limiting and versioning planned in rather than bolted on once something goes wrong. Where there's a data model behind it we work with PostgreSQL or MongoDB, and host on AWS using serverless functions, so you're not paying for capacity that sits idle most of the day.
Connecting to the tools you already use
More often the job is integration: joining systems that weren't built to talk to each other. These are the kinds of connections we build.
Payment gateways
Stripe, PayPal and card processors wired into checkout, including refunds and recurring payments — and handled so a failed charge doesn't lose you the order.
Couriers and fulfilment
Live shipping rates at checkout, label generation and tracking updates passed back to the customer without anyone copying numbers by hand.
CRM and marketing
Enquiries and orders dropped straight into the CRM or mailing tool your team works in, so nobody re-keys a contact form into a spreadsheet.
Accounting and stock
Orders, invoices and stock counts flowing into your finance or inventory system, so the figures match across the website and the back office.
Internal and legacy systems
An older line-of-business system connected to a modern website — usually the trickiest job, and the one that saves the most repeated manual work.
Webhooks and automation
Events in one system triggering an action in another, so the "someone runs it every morning" step quietly disappears.
Signs it's an integration job
Some work is obviously an API project. Other times it shows up as a symptom: staff retyping the same order into three different systems, stock that's right on the shop floor and wrong on the website, a "sync" that one person runs by hand before they've had their coffee. If the same data lives in more than one place and keeping the copies in step is somebody's job, that's usually something an integration can take off their plate.
What you get
- An API or integration designed around how your business actually moves data, not a generic template
- Error handling and retries, so a third party being briefly down doesn't lose a transaction
- Clear documentation for whoever maintains it next — including a future developer who isn't us
- Security considered up front: authentication, sensible access limits, and no secrets left in the open
- Support after launch, so when a provider changes their API you're not left stranded
The stack behind it
We work in TypeScript across the board, with Node.js on the server, REST or GraphQL depending on what fits, and PostgreSQL or MongoDB for storage. Hosting is typically AWS — Lambda, SQS and similar serverless pieces — which keeps costs down on the kind of traffic that comes in bursts rather than a steady stream. Fifteen-plus years of full-stack work means we've connected to a fair share of well-behaved APIs and badly documented ones, and we plan for both.
Need two systems to start talking?
Tell us what's connected to what — or what should be — and we'll talk through the most reliable way to do it. If you need the whole application built around that data rather than just the connections, our web application development page covers that, and online shops bring their own payment and stock work, which we cover under e-commerce web development.
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