lambda-zig: A Custom Runtime for AWS Lambda

This is a sample custom runtime built in zig. Simple projects will execute in <1ms, with a cold start init time of approximately 11ms.

Some custom build steps have been added to build.zig:

• zig build iam: Deploy and record a default IAM role for the lambda function
• zig build package: Package the lambda function for upload
• zig build deploy: Deploy the lambda function
• zig build run: Run the lambda function

Custom options:

• debug: boolean flag to avoid the debug symbols to be stripped. Useful to see error return traces in the AWS Lambda logs
• function-name: set the name of the AWS Lambda function
• payload: Use this to set the payload of the function when run using zig build run

Additionally, a custom IAM role can be used for the function by appending -- --role myawesomerole to the zig build deploy command. This has not really been tested. The role name is cached in zig-out/bin/iam_role_name, so you can also just set that to the full arn of your iam role if you'd like.

The AWS Lambda function is compiled as a linux ARM64 executable. Since the build.zig calls out to the shell for AWS operations, you will need AWS CLI v2.2.43 or greater.

This project vendors dependencies with gyro, so first time build should be done with gyro build. This should be working on zig master - certain build.zig constructs are not available in zig 0.8.1.

Caveats:

• Small inbound lambda payloads seem to be confusing requestz, which just never returns, causing timeouts
• Unhandled invocation errors seem to be causing the same problem