Features

• Serverless Framework

  • Added native AWS AppSync support directly in the Serverless Framework. This integration brings the functionality of the popular serverless-appsync-plugin into core, providing first-class support for deploying GraphQL APIs with AWS AppSync. Read more in our docs. (#13217)

    appSync:
      name: my-api
      schema: schema.graphql
      authentication:
        type: API_KEY
      dataSources:
        myTable:
          type: AMAZON_DYNAMODB
          config:
            tableName: !Ref MyTable
      resolvers:
        Query.getUser:
          dataSource: myTable
    

  • Added sls login aws sso command to authenticate with AWS using IAM Identity Center (SSO). Read more in our docs. (#13221)

    sls login aws sso --sso-session my-session
    

  • Added support for Ruby 3.4 runtime (ruby3.4). (#13215) - Thanks @dakatsuka!

Bug Fixes

• Serverless Framework

  • Fixed custom domain deployment failing when using --aws-profile credentials by migrating the domain plugin to AWS SDK v3 (#13109, #13178).
  • Fixed sls deploy failing with "Cannot find 'serverless-compose.yml|yaml'" for deeply nested service paths when using the esbuild plugin (#13201).
  • Fixed stale code deployment when using uv as the Python package installer by auto-reinstalling local packages based on their pyproject.toml name (#13169).
  • Fixed unhelpful "Stack with id does not exist" error when stack creation fails due to invalid Fn::ImportValue references. The framework now properly detects and reports the underlying CloudFormation error. Also fixed serverless deploy --verbose hanging when disableRollback: true is set (#13181).
  • Fixed regression in TypeScript type definitions where Resources only accepted Fn::Transform keys instead of arbitrary resource names (#13183).

• Serverless Container Framework

  • Fixed handling of multiple DNS validation records for ACM certificates in multi-domain configurations (#13206).

Maintenance

• Updated multiple dependencies including AWS SDK packages and upgraded @modelcontextprotocol/sdk to v1.25.2 which includes a security fix (#13216, CVE-2026-0621).