diff --git a/lib/build/bundle.js b/lib/build/bundle.js
index 065e9df59..f2e5e18d6 100644
--- a/lib/build/bundle.js
+++ b/lib/build/bundle.js
@@ -136,7 +136,18 @@ exports.Bundle = class {
       });
     }
 
-    work = work.then(() => files = files.concat(this.getBundledFiles()));
+    // Sort files by path to be sure they will alway be concatenated in the same order.
+    let bundleFiles = this.getBundledFiles()
+      .sort((a, b) => {
+        if (a.path > b.path) {
+          return -1
+        } else if (b.path > a.path) {
+          return 1
+        } else {
+          return 0
+        }
+      });
+    work = work.then(() => files = files.concat(bundleFiles));
 
     if (this.append.length) {
       work = work.then(() => addFilesInOrder(this, this.append, files));
@@ -211,7 +222,6 @@ exports.Bundle = class {
             content = Convert.removeMapFileComments(currentFile.contents);
           }
         }
-
         concat.add(currentFile.path, content, sourceMap ? JSON.stringify(sourceMap) : undefined);
       }