chore: setup github actions

.github/actions/setup/action.yml

@@ -0,0 +1,20 @@
+name: Setup
+
+runs:
+  using: composite
+  steps:
+    - name: Install node
+      uses: actions/setup-node@v3
+      with:
+        node-version: 16
+        cache: yarn
+    - name: Cache
+      uses: actions/cache@v2
+      id: cache
+      with:
+        path: '**/node_modules'
+        key: yarn-v1-${{ hashFiles('**/yarn.lock') }}
+    - name: Install
+      if: steps.cache.outputs.cache-hit != 'true'
+      run: yarn --prefer-offline
+      shell: bash

.github/workflows/ci.yml

@@ -0,0 +1,33 @@
+name: CI
+
+env:
+  CI: true
+
+on:
+  push:
+    branches: "*"
+  pull_request:
+    branches: "*"
+
+jobs:
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Set up environment
+        uses: ./.github/actions/setup
+      - name: Lint
+        run: yarn lint
+
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Set up environment
+        uses: ./.github/actions/setup
+      - name: Build
+        run: yarn build:mainnet