Page updated Jan 16, 2024

Lambda layer behavior updates

Amplify has updated the way Lambda layer versions are managed with Amplify CLI version 5.0.0. Amplify CLI enables you to configure Lambda layers to pull common code & assets for your Lambda functions into a centralized location.

In order to take advantage of the newest features and bug fixes, a one-way migration is required for layers created with an older Amplify CLI version. All developers working on a common Amplify project and any CI/CD pipelines should upgrade to the latest version of Amplify CLI.

How to initiate layer migration

Any update to an existing Lambda layer triggers a migration for that layer upon amplify push. Once the layers are migrated, the layers CANNOT be used with Amplify CLI below version 5.0.0.

Changes to layer behavior

Starting with the Amplify CLI version 5.0.0 and above, the following changes are coming to Lambda layers:

  • Ability to pin a function to always use the latest layer version of a Lambda layer
  • Layers auto-installs and packages dependencies listed within package.json or Pipfile
  • Ability to customize layer version descriptions
  • Ability to delete individual Lambda layer versions
  • Bug fix: Layer version updates are now managed globally, preventing multiple team members from creating conflicting layer versions