Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

I’m attempting to deploy a Lambda function behind API Gateway using LocalStack v4.0.12, but I’m running into issues because my company blocks access to the public.ecr.aws registry. We are only allowed to pull images from an internal/private container registry.

When LocalStack initializes Lambda, it attempts to pull AWS-provided runtime images from public.ecr.aws, which fails due to network restrictions. This prevents Lambda (and therefore API Gateway → Lambda integration) from working locally.

LocalStack attempts to pull Lambda runtime images from public.ecr.aws regardless of locally available images, causing Lambda initialization to fail in restricted corporate networks.

Expected Behavior

LocalStack should ideally provide one or more of the following options for restricted environments:

A way to configure an alternative registry for Lambda runtime images

A documented mechanism to fully disable remote image pulls and rely on preloaded local images

Support for mirrored runtime images hosted in a private registry

Clear documentation on which images are required and how to override them

How are you starting LocalStack?

With a docker run command

Steps To Reproduce

pull localstack from private registry where public registries are blocked.
start local stack.
attempt to deploy lambda function using terraform

Environment

- OS: arm64
- LocalStack:
  LocalStack version: 4.0.12
  LocalStack Docker image sha: sha256:948d165b599e614214950f5d87a738364cbe90af2de2f6959604bc84dc036d08
  LocalStack build date: 
  LocalStack build git hash:

Anything else?

localstack image is pulled from internal company, not from public registry