An API is a contract. Once external consumers depend on it, changing it is expensive and disruptive. Getting the design right upfront - resource modelling, error handling, authentication, versioning, rate limiting - saves significant rework later. We design and build APIs that consumers actually want to use.
What we deliver
API design and modelling. We design APIs starting from consumer needs, not database schemas. Resource modelling, URL structure, HTTP verb semantics, query parameters, pagination, filtering, and error response formats - all documented before a line of code is written.
RESTful API development. We build APIs in ASP.NET Core with proper content negotiation, status codes, HATEOAS where appropriate, and consistent error handling. We implement input validation, rate limiting, and request/response logging.
GraphQL services. For applications where clients need flexible querying, we design and implement GraphQL APIs with proper schema design, query complexity limits, DataLoader patterns for N+1 prevention, and subscription support.
gRPC services. For internal service-to-service communication where performance matters, we build gRPC services with proper protobuf schema management, streaming support, and deadline propagation.
API gateway and BFF patterns. We design API gateway layers using Azure API Management, YARP, or custom BFF services. Gateway composition, request transformation, caching, throttling, and authentication policies - all configured as code.
Authentication and authorisation. OAuth 2.0, OpenID Connect, Azure Entra ID, JWT validation, scope-based access control, API key management. We implement authentication that's secure without being painful for legitimate consumers.
Documentation and developer experience. OpenAPI/Swagger specifications, interactive documentation, SDK generation, and onboarding guides. Good documentation is the difference between an API that gets adopted and one that gets worked around.
Versioning and lifecycle
We implement versioning strategies (URL path, header, query string) that let you evolve APIs without breaking existing consumers. We design deprecation policies and sunset processes that give consumers adequate migration time.
Testing
Every API we build comes with comprehensive test coverage: unit tests for business logic, integration tests for the full HTTP pipeline, contract tests for consumer compatibility, and load tests for performance baselines.
Technologies
ASP.NET Core, Azure API Management, YARP, GraphQL (Hot Chocolate), gRPC, OAuth 2.0, Azure Entra ID, OpenAPI, Swagger UI, Postman collections.