AWS Lambda with .NET 10: Cold Starts, Layers, and ARM64

Why .NET on Lambda?

AWS Lambda supports .NET 10 natively. Combined with ARM64 Graviton2 processors, you get better price-performance than x86.

Lambda Handler

public class Function
{
    public async Task<APIGatewayProxyResponse> Handler(
        APIGatewayProxyRequest request, ILambdaContext ctx)
    {
        return new APIGatewayProxyResponse
        {
            StatusCode = 200,
            Body = JsonSerializer.Serialize(new { message = "Hello from .NET 10" })
        };
    }
}

Eliminating Cold Starts with SnapStart

# serverless.yml
functions:
  api:
    handler: MyApp::MyApp.Function::Handler
    runtime: dotnet10
    architecture: arm64
    snapStart: true

Lambda Layers for Shared Code

Package shared libraries as Lambda Layers to reduce deployment package size and share code across functions.