Custom API Development for Systems With No Ready-Made Connector
For applications and in-house tools that have no packaged connector, we design and build a custom API so partners, vendors or your own apps can read and write data securely.
What a Custom API Does
A custom API is a defined, secure gateway into one of your systems, built when no off-the-shelf connector exists for the software you run, or when you are the one exposing data to somebody else's app. It replaces manual file sharing, one-off scripts and unrestricted database access with a controlled set of requests that only return what the caller is allowed to see.
When a Custom Build Is the Right Answer
- Your core application was built for you and has no published API at all.
- A distributor or franchise app needs to read your stock and price list without touching your database directly.
- A kiosk, weighing scale or field device needs to post readings into your office system.
- A partner or auditor needs limited, read-only access to specific records, not your full system.
- An existing script or manual export has become the unofficial way two systems talk, and it breaks often.
What Goes Into the Build
Endpoint Design
We define the resources, methods and responses the API exposes, based on what the calling system actually needs, not a generic template.
Authentication and Access Control
Every caller is issued its own credentials, scoped to only the data and actions it is permitted, so one partner cannot see another's records.
Versioning
Endpoints are versioned from the first release so a future change does not break an integration nobody remembers building.
Rate Limiting and Monitoring
Calls are capped and logged so a runaway script or a compromised key cannot overload your system or go unnoticed.
Documentation and Handover
- Written API documentation covering every endpoint, its parameters and its error responses.
- A sandbox or test environment so the calling side can build against the API before going live.
- Source code and credentials issued in your name, not held by us.
Frequently asked questions
Do we need a custom API if our software already has one?
No. Where your ERP, CRM or e-commerce platform already publishes an API, we build against that instead of duplicating it. A custom API is for the gap: an in-house tool, an old application, or a scenario your existing API was never designed to cover.
Who can call our API once it exists?
Only whoever you issue credentials to. Each caller gets its own key or token scoped to specific endpoints and actions, so you can give a partner read-only access to stock levels without exposing pricing, orders or customer data.
What decides how much a custom API costs?
The number of endpoints, the complexity of the data behind each one, the authentication method required, and how much validation and error handling each request needs. A handful of read-only endpoints against clean data costs far less than a two-way API touching several tables with business rules attached.
What decides the timeline?
How well the underlying data and business rules are already understood, whether the system you are exposing has clear documentation of its own, and how much testing the calling side needs before it can integrate against the API.
Where does the API run?
On infrastructure in your name, such as your cloud account or server, so you control uptime, scaling and who has administrative access. We set it up and can manage it, but it is never hosted somewhere you cannot reach.
Can the API change as our systems change?
Yes. Because it is versioned and documented, new endpoints can be added or existing ones adjusted without breaking whoever is already calling it, as long as changes go through the same versioning discipline from day one.
Tell us what you need.
Send a short brief and one of our engineers will come back to you — usually the same day.
- No obligation
- We reply the same working day
- Your details stay private