Add eslint

.eslintrc.js

@@ -0,0 +1,17 @@
+module.exports = {
+  env: {
+    node: true,
+    browser: true,
+    commonjs: true,
+    es6: true
+  },
+  extends: "eslint:recommended",
+  globals: {
+    Atomics: "readonly",
+    SharedArrayBuffer: "readonly"
+  },
+  parserOptions: {
+    ecmaVersion: 2018
+  },
+  rules: {}
+};

package.json

@@ -7,7 +7,8 @@
     "start": "yarn run dev",
     "dev": "cross-env ELEVENTY_ENV=dev eleventy --serve",
     "build": "cross-env ELEVENTY_ENV=prod eleventy",
-    "test": "yarn run build"
+    "test": "yarn run build",
+    "lint": "eslint . --ext .js --cache"
   },
   "repository": {
     "type": "git",
@@ -39,5 +40,9 @@
     "eleventy-plugin-lazyimages": "liamfiddler/eleventy-plugin-lazyimages",
     "eleventy-plugin-local-images": "^0.2.0",
     "html-minifier": "^4.0.0"
+  },
+  "devDependencies": {
+    "eslint": "^6.1.0",
+    "eslint-plugin-ghost": "^0.4.0"
   }
 }