Django REST Framework (DRF) is one of the most mature API frameworks in any language. It handles serialization, authentication, permissions, and pagination — the plumbing you don't want to write from scratch.
Design First
Before writing any code, write your API contract. What endpoints exist? What do requests and responses look like? This forces clarity upfront and prevents endless refactoring. Tools like OpenAPI/Swagger make this easy and produce documentation as a byproduct.
Serializers Are Your Interface
DRF serializers do more than convert querysets to JSON. They validate input, handle relationships, and control what data is exposed. Treat them as your API's public interface — keep them thin, test them thoroughly, and resist adding business logic inside them.
Scaling Considerations
When traffic grows, your database becomes the bottleneck first. select_related and prefetch_related are your first line of defence against N+1 query problems. Beyond that, caching with Redis and using async views for I/O-heavy operations will take you a long way.