diff --git a/utils/build/build.js b/utils/build/build.js
index bcb73dc11a..908c219737 100644
--- a/utils/build/build.js
+++ b/utils/build/build.js
@@ -288,7 +288,7 @@ steps.push({
   ],
   shell: true,
   cwd: path.join(__dirname, '..', '..', 'packages', 'trace-viewer'),
-  concurrent: watchMode,
+  concurrent: watchMode, // feeds into trace-viewer's `public` directory, so it needs to be finished before trace-viewer build starts
 });
 
 // Build/watch web packages.