diff --git a/NOTICE b/NOTICE
index 3cbcecc156..312b59d128 100644
--- a/NOTICE
+++ b/NOTICE
@@ -20,6 +20,7 @@ under the licensing terms detailed in LICENSE:
 * Jeffrey Charles <jeffreycharles@gmail.com>
 * Vladimir Tikhonov <reg@tikhonov.by>
 * Duncan Uszkay <duncan.uszkay@shopify.com>
+* Surma <surma@surma.dev>
 
 Portions of this software are derived from third-party works licensed under
 the following terms:
diff --git a/cli/asc.js b/cli/asc.js
index 38e8eb56fb..8a38d2d3ba 100644
--- a/cli/asc.js
+++ b/cli/asc.js
@@ -1041,11 +1041,14 @@ exports.main = function main(argv, options, callback) {
     try {
       stats.writeCount++;
       stats.writeTime += measure(() => {
-        mkdirp(path.join(baseDir, path.dirname(filename)));
+        const dirPath = path.resolve(baseDir, path.dirname(filename));
+        filename = path.basename(filename);
+        const outputFilePath = path.join(dirPath, filename);
+        if (!fs.existsSync(dirPath)) mkdirp(dirPath);
         if (typeof contents === "string") {
-          fs.writeFileSync(path.join(baseDir, filename), contents, { encoding: "utf8" } );
+          fs.writeFileSync(outputFilePath, contents, { encoding: "utf8" } );
         } else {
-          fs.writeFileSync(path.join(baseDir, filename), contents);
+          fs.writeFileSync(outputFilePath, contents);
         }
       });
       return true;
diff --git a/cli/util/mkdirp.js b/cli/util/mkdirp.js
index bc7bffa8bb..59da6513f0 100644
--- a/cli/util/mkdirp.js
+++ b/cli/util/mkdirp.js
@@ -2,7 +2,7 @@
  * @fileoverview Recursive mkdir.
  * @license
  * Copyright 2010 James Halliday (mail@substack.net)
- * 
+ *
  * This project is free software released under the MIT/X11 license:
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
@@ -11,7 +11,7 @@
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
- * 
+ *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
@@ -24,9 +24,8 @@
  * THE SOFTWARE.
  */
 
-var path = require("path");
-var fs = require("fs");
-var _0777 = parseInt("0777", 8);
+const path = require("path");
+const fs = require("fs");
 
 module.exports = function mkdirp(p, opts, made) {
   if (!opts || typeof opts !== "object") {
@@ -34,7 +33,7 @@ module.exports = function mkdirp(p, opts, made) {
   }
   var mode = opts.mode;
   if (mode === undefined) {
-    mode = _0777 & (~process.umask());
+    mode = 0o777 & (~process.umask());
   }
   if (!made) made = null;
   p = path.resolve(p);
diff --git a/cli/util/utf8.js b/cli/util/utf8.js
index 0b37c859b1..076038b10b 100644
--- a/cli/util/utf8.js
+++ b/cli/util/utf8.js
@@ -20,7 +20,7 @@ var utf8 = exports;
 utf8.length = function utf8_length(string) {
     var len = 0,
         c = 0;
-    for (var i = 0; i < string.length; ++i) {
+    for (var i = 0, l = string.length; i < l; ++i) {
         c = string.charCodeAt(i);
         if (c < 128)
             len += 1;