diff --git a/declarations.d.ts b/declarations.d.ts
index 6a62225c9..9a3715663 100644
--- a/declarations.d.ts
+++ b/declarations.d.ts
@@ -77,6 +77,13 @@ declare module "neo-async" {
 		callback?: ErrorCallback<E>
 	): void;
 
+	export function eachLimit<T, E>(
+		arr: IterableCollection<T>,
+		limit: number,
+		iterator: AsyncIterator<T, E>,
+		callback?: ErrorCallback<E>
+	): void;
+
 	export function map<T, R, E>(
 		arr: T[] | IterableIterator<T>,
 		iterator: AsyncResultIterator<T, R, E>,
@@ -98,6 +105,7 @@ declare module "neo-async" {
 	): void;
 
 	export const forEach: typeof each;
+	export const forEachLimit: typeof eachLimit;
 }
 
 // There are no typings for @webassemblyjs/ast
diff --git a/lib/Compiler.js b/lib/Compiler.js
index 8ad6e7352..11f960f76 100644
--- a/lib/Compiler.js
+++ b/lib/Compiler.js
@@ -319,8 +319,9 @@ class Compiler {
 		const emitFiles = err => {
 			if (err) return callback(err);
 
-			asyncLib.forEach(
+			asyncLib.forEachLimit(
 				compilation.assets,
+				15,
 				(source, file, callback) => {
 					let targetFile = file;
 					const queryStringIdx = targetFile.indexOf("?");
diff --git a/package.json b/package.json
index 7c21e0098..73b69d351 100644
--- a/package.json
+++ b/package.json
@@ -9,7 +9,7 @@
     "@webassemblyjs/helper-module-context": "1.7.11",
     "@webassemblyjs/wasm-edit": "1.7.11",
     "@webassemblyjs/wasm-parser": "1.7.11",
-    "acorn": "^6.0.0",
+    "acorn": "^6.0.5",
     "acorn-dynamic-import": "^4.0.0",
     "ajv": "^6.1.0",
     "ajv-keywords": "^3.1.0",
diff --git a/yarn.lock b/yarn.lock
index 062e0aaad..d4d805049 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -303,10 +303,10 @@ acorn@^5.0.3, acorn@^5.6.0:
   resolved "https://registry.yarnpkg.com/acorn/-/acorn-5.7.2.tgz#91fa871883485d06708800318404e72bfb26dcc5"
   integrity sha512-cJrKCNcr2kv8dlDnbw+JPUGjHZzo4myaxOLmpOX8a+rgX94YeTcTMv/LFJUSByRpc+i4GgVnnhLxvMu/2Y+rqw==
 
-acorn@^6.0.0:
-  version "6.0.2"
-  resolved "https://registry.yarnpkg.com/acorn/-/acorn-6.0.2.tgz#6a459041c320ab17592c6317abbfdf4bbaa98ca4"
-  integrity sha512-GXmKIvbrN3TV7aVqAzVFaMW8F8wzVX7voEBRO3bDA64+EX37YSayggRJP5Xig6HYHBkWKpFg9W5gg6orklubhg==
+acorn@^6.0.5:
+  version "6.0.5"
+  resolved "https://registry.yarnpkg.com/acorn/-/acorn-6.0.5.tgz#81730c0815f3f3b34d8efa95cb7430965f4d887a"
+  integrity sha512-i33Zgp3XWtmZBMNvCr4azvOFeWVw1Rk6p3hfi3LUDvIFraOMywb1kAtrbi+med14m4Xfpqm3zRZMT+c0FNE7kg==
 
 ajv-errors@^1.0.0:
   version "1.0.1"