Add GitHub Actions

.github/workflows/main.yml

@@ -0,0 +1,20 @@
+name: main
+on:
+  - pull_request
+  - push
+jobs:
+  main:
+    name: ${{matrix.node}}
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: ${{matrix.node}}
+      - run: npm install
+      - run: npm test
+    strategy:
+      matrix:
+        node:
+          - lts/iron
+          - node

README.md

@@ -2,7 +2,6 @@
 
 ## TODO
 
-- github actions
 - test coverage
 - more tests?
 - typescript coverage

package.json

@@ -5,7 +5,9 @@
   "scripts": {
     "build": "micromark-build",
     "format": "prettier . -w --log-level warn && xo --fix",
-    "test": "node --test"
+    "test-dev": "node --conditions development --test",
+    "test-prod": "node --conditions production --test",
+    "test": "npm run test-dev && npm run test-prod"
   },
   "prettier": {
     "bracketSpacing": false,