diff --git a/extensions/html/build/update-grammar.js b/extensions/html/build/update-grammar.mjs
similarity index 86%
rename from extensions/html/build/update-grammar.js
rename to extensions/html/build/update-grammar.mjs
index 03d69042f5a..1fd330e0289 100644
--- a/extensions/html/build/update-grammar.js
+++ b/extensions/html/build/update-grammar.mjs
@@ -3,9 +3,8 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 // @ts-check
-'use strict';
 
-var updateGrammar = require('vscode-grammar-updater');
+import * as vscodeGrammarUpdater from 'vscode-grammar-updater';
 
 function patchGrammar(grammar) {
 	let patchCount = 0;
@@ -39,6 +38,6 @@ function patchGrammar(grammar) {
 
 const tsGrammarRepo = 'textmate/html.tmbundle';
 const grammarPath = 'Syntaxes/HTML.plist';
-updateGrammar.update(tsGrammarRepo, grammarPath, './syntaxes/html.tmLanguage.json', grammar => patchGrammar(grammar));
+vscodeGrammarUpdater.update(tsGrammarRepo, grammarPath, './syntaxes/html.tmLanguage.json', grammar => patchGrammar(grammar));
 
 
diff --git a/extensions/html/package.json b/extensions/html/package.json
index 4a8e8911d3c..aad035c05cc 100644
--- a/extensions/html/package.json
+++ b/extensions/html/package.json
@@ -9,7 +9,7 @@
     "vscode": "0.10.x"
   },
   "scripts": {
-    "update-grammar": "node ./build/update-grammar.js"
+    "update-grammar": "node ./build/update-grammar.mjs"
   },
   "contributes": {
     "languages": [
diff --git a/extensions/sql/build/update-grammar.js b/extensions/sql/build/update-grammar.mjs
similarity index 64%
rename from extensions/sql/build/update-grammar.js
rename to extensions/sql/build/update-grammar.mjs
index aecb5aa2704..40e2102e1e4 100644
--- a/extensions/sql/build/update-grammar.js
+++ b/extensions/sql/build/update-grammar.mjs
@@ -2,9 +2,7 @@
  *  Copyright (c) Microsoft Corporation. All rights reserved.
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
-'use strict';
-
-var updateGrammar = require('vscode-grammar-updater');
-updateGrammar.update('microsoft/vscode-mssql', 'syntaxes/SQL.plist', './syntaxes/sql.tmLanguage.json', undefined, 'main');
 
+import * as vscodeGrammarUpdater from 'vscode-grammar-updater';
 
+vscodeGrammarUpdater.update('microsoft/vscode-mssql', 'syntaxes/SQL.plist', './syntaxes/sql.tmLanguage.json', undefined, 'main');
diff --git a/extensions/sql/package.json b/extensions/sql/package.json
index ed0f77a4e37..20e19ad8dd0 100644
--- a/extensions/sql/package.json
+++ b/extensions/sql/package.json
@@ -9,7 +9,7 @@
     "vscode": "*"
   },
   "scripts": {
-    "update-grammar": "node ./build/update-grammar.js"
+    "update-grammar": "node ./build/update-grammar.mjs"
   },
   "contributes": {
     "languages": [