API development
and integration
services
Two systems that should share data, and a person in the middle copying it by hand. It works until the volume grows, or until they make a mistake nobody catches for a month.
* API development and integration services: REST and GraphQL APIs, third-party and legacy system integration. Built by us, or by developers we find you.
When systems do not talk to each other
Custom API development, and the integrations around it
An API is how one system lets another use it without a person in between. We build them, and we build the API integration services around them: connecting the tools you already pay for, pulling data out of a system that was never meant to share it, and keeping the whole arrangement working when one end changes.
Most of this work is unglamorous and specific. What matters is that it is documented, versioned and monitored, so that the integration is still working in two years and someone other than its author can change it.
Two ways to get it done
01
We build it
As an API development company, we take the work as a project: design, build, documentation and handover. Best when the need is defined and you would rather have the result delivered than run the work.
02
We find you the developers
Hire API developers onto your own team instead, permanently or on contract. Best when integration work is continuous and the knowledge should stay in your company.
What we build
What
we build
API development services end to end — API consulting, design, delivery and documentation — plus the software integration services around them.
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REST and GraphQL APIs
Designed to be used by someone who did not write them
Third-party API integration
Connecting the services you already depend on
Legacy system integration
System integration services for software never meant to share data
Webhooks and event delivery
With retries, ordering and a record of what was sent
Authentication and rate limiting
OAuth, keys, quotas and the abuse cases
Documentation and SDKs
The part that decides whether anyone adopts it
Versioning and migration
Changing an API without breaking its consumers
Monitoring and support
Knowing an integration broke before your customer tells you
API development questions
What people ask before any of this starts — including what we cannot promise.
An API (application programming interface) is a set of rules that lets one piece of software ask another for information or an action and get an answer back. It is how an online store passes an order to your stock system, or how your accounting software pulls in payments. API development means designing and building those connections, or the API your own software offers to others: what can be asked, how it is secured, how it is documented and how it changes over time without breaking the people who depend on it. Our plain-English guide to APIs explains the basics.
It depends on who is consuming it. REST is usually the right default for a public or partner API and for anything that has to be cached simply. GraphQL earns its place when many different clients need different shapes of the same data and you would otherwise be adding an endpoint a week. We will tell you which one your situation calls for rather than the one we feel like building.
That is most of the work. Legacy systems, and services that were never designed to talk to each other, are the normal case rather than the exception — payment and CRM providers, internal databases, and platforms whose only interface is a file drop or a screen.
They are part of the work, not an extra. Authentication, versioning, rate limiting, error handling, documentation and the tests that stop a change breaking a consumer are what decide whether an API is still usable in two years.
You do. The code, the documentation and the accounts are yours by default, in your own repositories, handed over as we go.
Next step
Discuss your
project
Tell us which systems need to talk to each other. We'll tell you what it would take, whether you need a project or a person, and plainly if we're not the right people for it.