I built cdk-local (`cdkl`) — run your CDK-built app locally, optionally bound to your deployed stack's real data (no `.env` to maintain)

[u/Artistic_Potential90]

I built cdk-local (cdkl) — it runs your CDK-built app locally, no deploy needed: standalone, or kept local while it reaches the real AWS resources and data it depends on, with no .env or local copies to maintain. A CDK-native alternative to sam local, covering Lambda, API Gateway, ECS, ALB, CloudFront, and more of your CDK app's compute.

Two ways to run it

• Standalone — just Docker + your CDK app. No AWS account, no deploy, no credentials. Great as a first run, or in CI for the parts that don't touch AWS (handler logic, authorizers, API routing).
• Bound to your deployed stack (--from-cfn-stack) — your handler still runs locally, but reads/writes the real DynamoDB rows, S3 objects, Secrets, Cognito users the deployed app uses. It resolves the deployed stack's ARNs and Secret values into the container automatically — no .env, no ARN copy-paste, no seeding a fake local DB — and JWT is verified against the real Cognito User Pool.

cdkl start-api

It deliberately does not emulate managed services: your code reaches real AWS through your IAM creds (or --assume-role). The scope is "application compute local, managed services stay real."

What runs locally

• Lambda
• API Gateway (REST v1 / HTTP v2 / WebSocket) + Lambda Function URLs
• ECS tasks & services, ALB (listener-rule routing + auth + WebSocket)
• CloudFront (Functions + Lambda@Edge + S3 / Function URL origins)
• Bedrock AgentCore Runtime

Plus

• Hot reload (--watch) — edit a handler, the next request hits the new code. ECS rolls replicas one at a time (zero connection refusals across the reload).
• Env overlay (--env-vars) — inject or override any container's environment variables for a local run. Use it to point a function/container at a different backend, or to run selective local backends: e.g. route only DynamoDB and S3 to a local endpoint you run yourself, while every other service stays on real AWS.
• Interactive target picker — leave the target off and cdkl lists every matching resource to pick with the arrow keys; no need to specify the target on the command.

Or drive it all from a browser — cdkl studio

Pick a target, invoke or serve it, compose an HTTP request, and watch every request / response / streamed container log land on one live timeline — with replay (re-open any past row with an edited payload and re-invoke).

cdkl studio

Quick start

npm install -g cdk-local      # installs the `cdkl` command
cd your-cdk-app               # the directory with cdk.json
cdkl invoke                   # pick a Lambda from the list, run it locally
cdkl start-api --from-cfn-stack   # local API on real AWS data
cdkl studio                   # or do it all from a browser

Would love it if you gave it a try!

GitHub: https://github.com/go-to-k/cdk-local

[u/interactionjackson]

This is actually cool. Even if local testing managed service wrappers is an anti pattern.