diff --git a/lib/node/closure-compiler.js b/lib/node/closure-compiler.js
index 379253bd..4f041658 100644
--- a/lib/node/closure-compiler.js
+++ b/lib/node/closure-compiler.js
@@ -36,7 +36,9 @@ var contribPath = path.dirname(compilerPath) + '/contrib';
 function Compiler(args, extraCommandArgs) {
   this.commandArguments = (extraCommandArgs || []).slice();
 
-  this.commandArguments.push('-jar', Compiler.JAR_PATH);
+  if (Compiler.JAR_PATH) {
+    this.commandArguments.push('-jar', Compiler.JAR_PATH);
+  }
 
   if (Array.isArray(args)) {
     this.commandArguments = this.commandArguments.concat(args.slice());