diff --git a/lib/wpt/index.js b/lib/wpt/index.js
index 601b207b..4438d340 100644
--- a/lib/wpt/index.js
+++ b/lib/wpt/index.js
@@ -79,9 +79,12 @@ export class WPTUpdater {
     await removeDirectory(this.fixtures(this.path));
 
     this.cli.startSpinner('Pulling assets...');
-    await Promise.all(assets.map(
-      (asset) => this.pullTextFile(fixtures, asset.name)
-    ));
+    for (let i = 0; i < assets.length; i += 10) {
+      const chunk = assets.slice(i, i + 10);
+      await Promise.all(chunk.map(
+        (asset) => this.pullTextFile(fixtures, asset.name)
+      ));
+    }
     this.cli.stopSpinner(`Downloaded ${assets.length} assets.`);
 
     return assets;