리드미에 핵심 경험 요약 추가 #390

	name: CI Pipeline

	on:
	pull_request:
	types: [ opened, reopened, synchronize ]
	branches:
	- develop
	- main

	jobs:
	build:
	name: Lint, Build and Test
	runs-on: ubuntu-latest

	strategy:
	matrix:
	project: [ frontend, backend ]

	steps:
	- name: Checkout Repository
	uses: actions/checkout@v3
	with:
	fetch-depth: 2

	- name: Fetch base branch
	run: \|
	echo "BASE_BRANCH=${{ github.event.pull_request.base.ref }}" >> $GITHUB_ENV
	git fetch origin $BASE_BRANCH --depth=1

	- name: Check for changes in ${{ matrix.project }}
	id: changes
	run: \|
	if git diff --name-only origin/$BASE_BRANCH HEAD \| grep -q "^${{ matrix.project }}/"; then
	echo "changed=true" >> $GITHUB_ENV
	else
	echo "changed=false" >> $GITHUB_ENV
	fi

	- name: Set up Node.js
	if: env.changed == 'true'
	uses: actions/setup-node@v3
	with:
	node-version: '20'

	- name: Install Dependencies for ${{ matrix.project }}
	if: env.changed == 'true'
	run: yarn install --frozen-lockfile # yarn.lock 을 기준으로 설치하며, 의존성 재해석 방지
	working-directory: ${{ matrix.project }}

	- name: Lint ${{ matrix.project }}
	if: env.changed == 'true'
	run: yarn format-check
	working-directory: ${{ matrix.project }}

	- name: Build ${{ matrix.project }}
	if: env.changed == 'true'
	run: yarn build
	working-directory: ${{ matrix.project }}

	- name: Test ${{ matrix.project }}
	if: env.changed == 'true'
	run: \|
	echo "${{ secrets.DOT_ENV_PROD }}" > ${{ github.workspace }}/backend/.env
	yarn test
	working-directory: ${{ matrix.project }}

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