diff --git a/package.json b/package.json
index ff019780..8e1ccf34 100644
--- a/package.json
+++ b/package.json
@@ -19,10 +19,11 @@
     "updates": "^4.0.0"
   },
   "scripts": {
-    "build": "npm run update && npm run build:cm",
+    "build": "npm run update && npm run versions && npm run build:cm",
     "build:cm": "node tools/update-libraries.js && node tools/update-codemirror-themes.js",
     "lint": "eslint **/*.js || true",
     "update": "updates -u && npm update",
-    "zip": "node tools/zip.js"
+    "versions": "node tools/update-versions",
+    "zip": "npm run versions && node tools/zip.js"
   }
 }
diff --git a/tools/update-versions.js b/tools/update-versions.js
new file mode 100644
index 00000000..658ac5d9
--- /dev/null
+++ b/tools/update-versions.js
@@ -0,0 +1,62 @@
+#!/usr/bin/env node
+'use strict';
+
+const fs = require('fs-extra');
+const path = require('path');
+const root = path.join(__dirname, '..');
+
+const manifest = require(`${root}/manifest.json`);
+const pkg = require(`${root}/package.json`);
+
+const good = '\x1b[32m%s\x1b[0m';
+const warn = '\x1b[36m%s\x1b[0m';
+
+function exit(err) {
+  if (err) {
+    console.error(err);
+  }
+  process.exit(err ? 1 : 0);
+}
+
+function verToArray(v) {
+  return v.replace('v', '').split('.').map(Number);
+}
+
+// Simple compare function since we can't require semverCompare here
+function compare(v1, v2) {
+  if (v1 === v2) {
+    return 0;
+  }
+  const [maj1, min1, pat1] = verToArray(v1);
+  const [maj2, min2, pat2] = verToArray(v2);
+  const majMatch = maj1 === maj2;
+  const minMatch = min1 === min2;
+  if (
+    maj1 > maj2 ||
+    majMatch && min1 > min2 ||
+    majMatch && minMatch && pat1 > pat2
+  ) {
+    return 1;
+  }
+  return -1;
+}
+
+async function updateVersions() {
+  const result = compare(manifest.version, pkg.version);
+  let file, obj;
+  if (result === 0) {
+    return console.log(good, 'Manifest & package versions match');
+  } else if (result > 0) {
+    pkg.version = manifest.version;
+    file = 'package.json';
+    obj = pkg;
+  } else {
+    manifest.version = pkg.version;
+    file = 'manifest.json';
+    obj = manifest;
+  }
+  console.log(warn, `Updating ${file} to ${pkg.version}`);
+  return fs.writeFile(`${root}/${file}`, JSON.stringify(obj, null, '  ') + '\n');
+}
+
+updateVersions().catch(err => exit(err));