While practical experience, through projects or contributions to open-source API projects, can be a strong indicator of capability, you should be able to verify that your API developer has direct knowledge of these areas:
1. Programming Languages:
JavaScript/Node.js: For RESTful services, GraphQL APIs.
Python: Popular for backend services, especially with frameworks like Flask or Django for API development.
Java/Go: Common in enterprise environments for scalable backend services.
C#: With .NET Core for cross-platform API development.
2. API Design and Protocols:
REST/HTTP: Understanding of REST principles, HTTP methods, status codes.
GraphQL: Ability to design and implement GraphQL schemas and resolvers.
gRPC: Knowledge for high-performance scenarios where protocol buffers are used.
3. Security:
OAuth 2.0, OpenID Connect, JWT: Skills in implementing secure authentication and authorization mechanisms.
TLS/SSL: Understanding of secure communication over networks.
4. Database Management:
SQL and NoSQL: Familiarity with databases like PostgreSQL, MySQL, or MongoDB for data handling in APIs.
5. API Management:
API Gateways: Experience with tools like Kong, Apigee, or AWS API Gateway.
Documentation: Ability to use tools like Swagger/OpenAPI for API documentation.
6. DevOps and Infrastructure:
Docker, Kubernetes: For containerization and orchestration, especially in microservices environments.
CI/CD: Understanding of continuous integration and deployment pipelines.
7. Asynchronous Programming:
Concurrency and Parallelism: Particularly for handling high loads or real-time data processing.
8. Testing:
Unit, Integration, and Load Testing: Experience with frameworks like Jest, Postman, or specialized API testing tools.
9. Soft Skills:
Communication: To explain technical details to teams and stakeholders.
Problem-Solving: Given the complexities involved in API development.
Collaboration: For working within or across teams, especially in API-first development strategies.
10. Emerging Skills:
Knowledge of Cloud Platforms: AWS, Azure, GCP, especially services like Lambda, Functions, or Cloud Run.
Understanding of Machine Learning APIs: To integrate or expose AI functionalities.