Minimal APIs are an endpoint-first way to build HTTP APIs in ASP.NET Core by mapping routes directly to handlers (no controllers required). They’re best for teams building small-to-medium, bounded services (microservices, BFFs, webhooks, internal APIs) that want fast iteration with less ceremony, as long as you add structure early . They solve the “too much framework for a small API” problem, and they matter because choosing the wrong model (or letting Program.cs become a dumping ground) creates long-term maintenance pain.

What decision should you make: Minimal APIs or Controllers?

Use this checklist and pick the first match.

Choose Minimal APIs when your API is bounded and you can enforce conventions

You’re building a focused service boundary (webhooks, microservice, BFF, internal tool API).

You can enforce a module convention (route groups + one file per feature).

Your team likes explicit routing and fluent metadata (OpenAPI tags, response types).

You want cross-cutting behavior via middleware +…