This is the Buildspec file for AWS CodePipeline - Build React Native App https://medium.com/@prashant_48386/aws-codepipeline-build-react-native-app-dc47e0575e0c

buildspec.yml

version: 0.2
phases:
  install:
    runtime-versions:
      android: 29
      java: corretto8
      nodejs: 10
    commands:
      - pwd
  pre_build:
    commands:
      - echo Pre Build started on `date`
      - npm --version
      - npm install -g react-native-cli
      - yarn
      - react-native link
      - cd android
      - pwd
      
  build:
    commands:
      - echo Build started on `date`
      - ./gradlew clean
      - ./gradlew assembleRelease
  post_build:
    commands:
      - echo Build completed on `date`
artifacts:
  files:
    - /app/build/outputs/apk/release/*.apk
  discard-paths: yes