API Development — Building the Connections That Make Your Systems Work Together
An API is the interface through which your digital systems communicate — and a well-designed API is what enables automation, data consistency and scalability across your technology stack. Expert SEO Online builds custom REST and GraphQL APIs that connect your platforms, expose your data to authorised consumers and enable the integrations your business depends on. We have been building APIs for enterprise organisations and growing businesses since 1999.
APIs Built for Security, Performance and Longevity
Our API development covers endpoint design, authentication and authorisation (OAuth 2.0, JWT, API keys), rate limiting, versioning strategy, error handling, logging and documentation. We build APIs that are intuitive to consume, well-documented and designed for the traffic volumes they will realistically experience.
API development works alongside our API integration capability — we can build your own API and connect it to the third-party services your business relies on within the same project. For data-intensive applications, database architecture decisions and API design are planned together to ensure query performance aligns with API response requirements. See also our database design service.
Frequently Asked Questions
What is the difference between REST and GraphQL?
REST uses fixed endpoints returning predefined data — well-suited for simple, stable integrations. GraphQL allows clients to request exactly the data they need in a single query — better for complex, data-intensive applications. We advise on the right choice for your use case.
Do you provide API documentation?
Yes — always. Every API includes comprehensive documentation covering endpoints, request/response formats, authentication, error codes and rate limiting, using OpenAPI/Swagger specifications where appropriate.