diff --git a/lib/integration/AdaptFramework/build.js b/lib/integration/AdaptFramework/build.js
index 25b0160..523f925 100644
--- a/lib/integration/AdaptFramework/build.js
+++ b/lib/integration/AdaptFramework/build.js
@@ -28,10 +28,17 @@ export default async function adaptBuild ({
     ].filter(Boolean).join(' ');
     exec(cmd, { cwd }, (error, stdout, stderr) => {
       if(error || stderr) {
-        const matches = stdout.match(/>> Error:\s(.+)\s/);
+        // Surface the salient failure rather than the whole grunt transcript:
+        // a '>> Error:' task message, else a bare 'Error:' line (e.g. a rollup
+        // load failure from the javascript task), else the failing-task warning.
+        // Fall back to the full stdout only when none of those are present.
+        const matches = stdout.match(/>> Error:\s(.+)/) ||
+          stdout.match(/^Error:\s(.+)/m) ||
+          stdout.match(/(Warning: Task .+ failed)/);
         const e = new Error('grunt tasks failed')
         e.cmd = cmd;
         e.raw = matches?.[1] ?? stdout;
+        e.stdout = stdout;
         e.source = error;
         e.stderr = stderr;
         return reject(e)