amplify.yml backend phase in monorepo

[scott-elgaard]

Environment information

System:
  OS: Windows 11 10.0.22631
  CPU: (16) x64 13th Gen Intel(R) Core(TM) i7-13620H
  Memory: 2.14 GB / 31.68 GB
Binaries:
  Node: 20.14.0 - C:\Program Files\nodejs\node.EXE
  Yarn: undefined - undefined
  npm: 10.8.1 - C:\Program Files\nodejs\npm.CMD
  pnpm: undefined - undefined
NPM Packages:
  @aws-amplify/auth-construct: 1.3.0
  @aws-amplify/backend: 1.2.1
  @aws-amplify/backend-auth: 1.1.3
  @aws-amplify/backend-cli: 1.2.5
  @aws-amplify/backend-data: 1.1.3
  @aws-amplify/backend-deployer: 1.1.0
  @aws-amplify/backend-function: 1.4.0
  @aws-amplify/backend-output-schemas: 1.2.0
  @aws-amplify/backend-output-storage: 1.1.1
  @aws-amplify/backend-secret: 1.1.1
  @aws-amplify/backend-storage: 1.1.2
  @aws-amplify/cli-core: 1.1.2
  @aws-amplify/client-config: 1.3.0
  @aws-amplify/deployed-backend-client: 1.4.0
  @aws-amplify/form-generator: 1.0.1
  @aws-amplify/model-generator: 1.0.5
  @aws-amplify/platform-core: 1.1.0
  @aws-amplify/plugin-types: 1.2.1
  @aws-amplify/sandbox: 1.2.1
  @aws-amplify/schema-generator: 1.2.1
  aws-amplify: 6.6.0
  aws-cdk: 2.156.0
  aws-cdk-lib: 2.156.0
  typescript: 5.5.4
AWS environment variables:
  AWS_NODEJS_CONNECTION_REUSE_ENABLED = 1
  AWS_SDK_LOAD_CONFIG = 1
  AWS_STS_REGIONAL_ENDPOINTS = regional
No CDK environment variables

Describe the bug

When running a build in amplify my backend phase never triggers from this amplify.yml

version: 1
applications:
  - appRoot: .
    backend:
      phases:
        preBuild:
          commands:
            - echo "Backend preBuild step started"
            - amplify --version
            - echo "Backend preBuild step finished"
        build:
          commands:
            - echo "Backend build step started"
            - amplify status
            - amplifyPush --simple
            - amplify codegen models
            - mkdir -p cloud/lib/amplify/lib
            - amplify export --out cloud/lib/amplify/lib
            - echo "Backend build step completed"
        postBuild:
          commands:
            - echo "Custom postBuild step completed"
      artifacts:
        baseDirectory: cloud/lib/amplify
        files:
          - '**/*'
  - appRoot: ui/corvision
    frontend:
      phases:
        preBuild:
          commands:
            - echo "Frontend preBuild step started"
            - export FLUTTER_ROOT=$HOME/flutter
            - mkdir -p $FLUTTER_ROOT
            - curl -o flutter.tar.xz https://storage.googleapis.com/flutter_infra_release/releases/stable/linux/flutter_linux_3.24.2-stable.tar.xz
            - tar xf flutter.tar.xz -C $HOME
            - export PATH="$PATH:$FLUTTER_ROOT/bin"
            - flutter precache
            - flutter --version
            - echo "Frontend preBuild step completed"
        build:
          commands:
            - echo "Frontend build step started"
            - flutter pub get
            - flutter build web --release --verbose
            - echo "Frontend build step completed"
      artifacts:
        baseDirectory: build/web
        files:
          - '**/*'

Not sure if there is something wrong with my amplify.yml or what but I've tried a bunch of different commands and formats in the backend phase and none of them trigger/get called.

appID: d1gwep07t2uubt Region: use-east-2

Reproduction steps

try to deploy in amplify