appengine/bower sample fails to deploy

Running "gcloud app deploy" in appengine/bower fails with the following error:

3422 silly install resolved     _resolved: 'https://registry.npmjs.org/mime-types/-/mime-types-2.1.11.tgz' } ]
3423 info install [email protected] into /app/node_modules/express/node_modules/accepts
3424 info install [email protected] into /app/node_modules/express/node_modules/accepts
3425 info installOne [email protected]
3426 verbose installOne of negotiator to /app/node_modules/express/node_modules/accepts not in flight; installing
3427 info installOne [email protected]
3428 verbose installOne of mime-types to /app/node_modules/express/node_modules/accepts not in flight; installing
3429 silly install resolved [ { name: 'media-typer',
3429 silly install resolved     description:cat: write error: Resource temporarily unavailable
The command '/bin/sh -c npm install --unsafe-perm ||   ((if [ -f npm-debug.log ]; then       cat npm-debug.log;     fi) && false)' returned a non-zero code: 1
ERROR
ERROR: build step "gcr.io/cloud-builders/docker@sha256:ac2af9efbff12cd7020c1bfeca2ef4cb4a2c87de30709edcffaf5cd292b5a421" failed: exit status 1

ERROR: (gcloud.app.deploy) Error Response: [2] Build failed; check build logs for details