API Design & Contract-First Development
Once an API has more than one consumer, the contract matters more than any single implementation. An OpenAPI spec-first workflow, deliberate resource modelling, a clear versioning strategy, and breaking-change management stop a back-end change from silently breaking a front-end or another team. Consumer-driven contract testing (e.g. Pact) catches those breaks automatically, and knowing the alternatives to REST — GraphQL, SOAP, EDI, RPC — helps you make an informed choice instead of defaulting to REST out of habit.
Starting Points
- OpenAPI Initiative. openapis.org.
- W3C. SOAP Version 1.2.
- IBM. What is Electronic Data Interchange (EDI).
- API implementation
Key Points
- You use REST naming conventions correctly.
- You explain the difference between stateful and stateless.
- You apply one or more versioning strategies.
- You know which HTTP method to use in which case.
- You write a Swagger/OpenAPI YAML file describing an API.
- You have a basic understanding of GraphQL, SOAP, EDI, and RPC.
- You use a tool for testing an API (Postman, Bruno, SoapUI), including inside a CI/CD pipeline.