Auto linter

.eslintrc.json

@@ -0,0 +1,33 @@
+{
+  "parser": "@typescript-eslint/parser",
+  "parserOptions": {
+    "ecmaVersion": 12,
+    "sourceType": "module"
+  },
+  "plugins": [
+    "@typescript-eslint"
+  ],
+  "extends": [
+    "eslint:recommended",
+    "plugin:@typescript-eslint/recommended"
+  ],
+  "overrides": [
+    {
+      "files": [
+        "src/**/*.js",
+        "src/**/*.ts"
+      ]
+    }
+  ],
+  "rules": {
+    "@typescript-eslint/no-unused-vars": "error",
+    "@typescript-eslint/consistent-type-definitions": [
+      "error",
+      "type"
+    ]
+  },
+  "env": {
+    "node": true,
+    "es2021": true
+  }
+}

.github/workflows/linter.yaml

@@ -0,0 +1,21 @@
+name: linter
+on:
+  pull_request:
+
+jobs:
+  eslint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: checkout code
+        uses: actions/checkout@v4
+
+      - name: setup node
+        uses: actions/setup-node@v4
+        with:
+          node-version: "20.x"
+
+      - name: install dependencies
+        run: npm install
+
+      - name: run eslint
+        run: npm run lint

package.json

@@ -5,7 +5,7 @@
   "main": "index.js",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1",
-    "lint": "eslint --ignore-path .eslintignore --ext .js,.ts",
+    "lint": "eslint src --ignore-path .eslintignore --ext .js,.ts",
     "start": "ts-node src/index.ts"
   },
   "repository": {