diff --git a/dev/fixAntlr4.js b/dev/fixAntlr4.js
index ef8499b8f..6f9fd7473 100644
--- a/dev/fixAntlr4.js
+++ b/dev/fixAntlr4.js
@@ -22,3 +22,4 @@ const babelContents = {
 fs.writeJSONSync(antlr4BabelPath, babelContents);
 
 execSync('npm install', { cwd: antlr4Path });
+execSync('npm run build', { cwd: antlr4Path });