ampx sandbox fails with tsx@4.20.1 (ENOENT: no such file or directory)

[zacnel909]

Environment information

System:
  OS: macOS 14.6.1
  CPU: (8) arm64 Apple M2
  Memory: 173.02 MB / 8.00 GB
  Shell: /bin/zsh
Binaries:
  Node: 22.13.1 - ~/.nvm/versions/node/v22.13.1/bin/node
  Yarn: 1.22.22 - ~/.nvm/versions/node/v22.13.1/bin/yarn
  npm: 10.9.2 - ~/.nvm/versions/node/v22.13.1/bin/npm
  pnpm: undefined - undefined
NPM Packages:
  @aws-amplify/auth-construct: 1.8.1
  @aws-amplify/backend: 1.16.1
  @aws-amplify/backend-ai: Not Found
  @aws-amplify/backend-auth: 1.7.1
  @aws-amplify/backend-cli: 1.7.2
  @aws-amplify/backend-data: 1.6.1
  @aws-amplify/backend-deployer: 2.1.1
  @aws-amplify/backend-function: 1.14.1
  @aws-amplify/backend-output-schemas: 1.6.0
  @aws-amplify/backend-output-storage: 1.3.1
  @aws-amplify/backend-secret: 1.4.0
  @aws-amplify/backend-storage: 1.4.1
  @aws-amplify/cli-core: 2.1.1
  @aws-amplify/client-config: 1.7.0
  @aws-amplify/data-construct: 1.16.1
  @aws-amplify/data-schema: 1.21.0
  @aws-amplify/deployed-backend-client: 1.7.0
  @aws-amplify/form-generator: 1.2.1
  @aws-amplify/model-generator: 1.2.0
  @aws-amplify/platform-core: 1.9.0
  @aws-amplify/plugin-types: 1.10.1
  @aws-amplify/sandbox: 2.1.2
  @aws-amplify/schema-generator: 1.4.0
  @aws-cdk/toolkit-lib: 0.3.2
  aws-amplify: 6.15.0
  aws-cdk-lib: 2.189.1
  typescript: 5.8.3
npm warn exec The following package was not found and will be installed: cdk@2.1018.1
No AWS environment variables
No CDK environment variables

Describe the bug

I run

npm create amplify@latest
npx ampx sandbox

and receive the following error:

[ERROR] [BackendBuildError] Unable to deploy due to CDK Assembly Error
  ∟ Caused by: [_AssemblyError] Assembly builder failed
    ∟ Caused by: [Error] ENOENT: no such file or directory, open '[project_root]/node_modules/@aws-amplify/backend-output-schemas/lib/index.js?tsx-namespace=1749693106808'

After troubleshooting, I found that this only happens when using tsx@4.20.1 or newer.
Pinning tsx to 4.19.4 in package.json resolves the issue.

This breaks both new and existing projects if tsx is upgraded.

Reproduction steps

1. Open a terminal and create a new directory:

mkdir amplify-tsx-test
cd amplify-tsx-test

2. Initialize a new Amplify Gen 2 project:

npm create amplify@latest

3. Start the Amplify local sandbox:

npx ampx sandbox

4.Observe the error:

[ERROR] [BackendBuildError] Unable to deploy due to CDK Assembly Error
  ∟ Caused by: [_AssemblyError] Assembly builder failed
    ∟ Caused by: [Error] ENOENT: no such file or directory, open '[project_root]/node_modules/@aws-amplify/backend-output-schemas/lib/index.js?tsx-namespace=...'

Workaround:
Pin tsx to 4.19.4 in your package.json, run npm install, and the error is resolved.

[ShadowCat567]

You're right, looks like the latest release of tsx is not compatible with versions of node that are not the latest - privatenumber/tsx#724
If you don't want to pin you can try upgrading to Node version 22.16.0. Will be looking into what can be done to mitigate this problem in this repo.

[ShadowCat567]

We decided to pinning tsx version to 4.19.4 is the best way forward until they make a release that is compatible with amplify-backend. Updated package.json files with tsx pinned are a part of our most recent release which happened less than an hour ago.
Thank you for bringing the issue with tsx's most recent version to our attention! (I'm going to close this now, let us know if you continue to have issues with tsx version)