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cdklabs/awscdk-lambda-dotnet

AWS Lambda .NET Library


cdk-constructs: Experimental

The APIs of higher level constructs in this module are experimental and under active development. They are subject to non-backward compatible changes or removal in any future version. These are not subject to the Semantic Versioning model and breaking changes will be announced in the release notes. This means that while you may use them, you may need to update your source code when upgrading to a newer version of this package.


This library provides constructs for .NET Lambda functions.

To use this module you will either need to have .NET SDK installed (.NET 6.0 or later) with the AWS Lambda Tools for .NET or Docker installed.

.NET Function

Define a DotNetFunction:

new dotnet.DotNetFunction(this, 'MyFunction', {
  projectDir: 'src/MyFunction'
});

All other properties of lambda.Function are supported, see also the AWS Lambda construct library.

Custom Runtime and Native AOT

With this construct it is possible to use a custom runtime by setting the runtime to PROVIDED_AL2. This allows you to run unsupported .NET runtime versions like .NET 7.0 or Native AOT. Setting the runtime to PROVIDED_AL2 will instruct CDK and the AWS Lambda Tools for .NET to build your project in a Docker container based of Amazon Linux 2. An example can be found below.

new dotnet.DotNetFunction(this, 'MyFunction', {
  projectDir: 'src/MyFunction',
  runtime: lambda.Runtime.PROVIDED_AL2,
  bundling: {
    msbuildParameters: ['/p:PublishAot=true'],
  },
});

Make sure <AssemblyName>bootstrap</AssemblyName> is set in the csproj file as this is required by the custom runtime.

Publishing your application with Native AOT requires you to use the same processor architecture for the Lambda function as for your build environment. Without specification, the construct automatically selects the processor architecture of the machine where CDK is building your project.

Community Extensions

We encourage the development of Community Service Extensions that support advanced features. Here are some useful extensions that we have reviewed:

Please submit a pull request so that we can review your service extension and list it here.