Introduction
Minimal APIs in .NET 8 let you build HTTP APIs with minimal ceremony. No controllers, no startup classes — just clean endpoint definitions.
Step 1: Create the Project
dotnet new web -n MinimalApiDemo
cd MinimalApiDemo
Step 2: Define Your First Endpoint
Open Program.cs and add a simple GET endpoint:
var builder = WebApplication.CreateBuilder(args);
var app = builder.Build();
app.MapGet("/api/hello", () => "Hello from Minimal API!");
app.Run();
Step 3: Add CRUD Endpoints
Create endpoints for a simple Todo API with GET, POST, PUT, and DELETE operations. Use an in-memory list to start, then migrate to Entity Framework Core.
Step 4: Add Validation & Error Handling
Integrate FluentValidation or use the built-in validation attributes. Add global error handling middleware for consistent error responses.
Step 5: Add Swagger Documentation
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
// ...
app.UseSwagger();
app.UseSwaggerUI();
Configure Swagger to document your API endpoints with descriptions, request/response examples, and authentication requirements.
