Introduction to .NET 8 Minimal APIs

With the release of .NET 8, building microservices and RESTful APIs has never been faster or more efficient. The new minimal API pattern reduces boilerplate significantly while maintaining full access to the ASP.NET Core pipeline.

Setting Up Your Project

First, create a new minimal API project using the .NET CLI:

dotnet new webapi -minimal -n MyScalableApi
cd MyScalableApi
dotnet run

Creating Your First Endpoint

The minimal API style is clean and expressive. Here’s a simple CRUD endpoint:

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddDbContext<AppDbContext>(opt =>
    opt.UseSqlServer(builder.Configuration.GetConnectionString("Default")));

var app = builder.Build();

// GET all items
app.MapGet("/api/products", async (AppDbContext db) =>
    await db.Products.ToListAsync());

// GET by ID
app.MapGet("/api/products/{id}", async (int id, AppDbContext db) =>
    await db.Products.FindAsync(id) is Product p
        ? Results.Ok(p)
        : Results.NotFound());

// POST create
app.MapPost("/api/products", async (Product product, AppDbContext db) =>
{
    db.Products.Add(product);
    await db.SaveChangesAsync();
    return Results.Created($"/api/products/{product.Id}", product);
});

app.Run();

Performance Benchmarks

In benchmarks, .NET 8 minimal APIs significantly outperform previous versions. The key improvements include:

  • Native AOT compilation — dramatically faster startup times
  • Frozen collections — immutable, cache-friendly data structures
  • Improved JSON serialization via System.Text.Json

Configuration Example

{
  "ConnectionStrings": {
    "Default": "Server=localhost;Database=MyApi;Trusted_Connection=True;"
  },
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft.AspNetCore": "Warning"
    }
  }

💡 Tip: Use builder.Services.AddOutputCache() with .NET 8 to add response caching with zero configuration.

Conclusion

.NET 8 represents a massive leap forward for API development. Whether you are building a monolith or a distributed microservices architecture, the new features give you powerful tools without sacrificing simplicity.