The other downsides are the deploys are slower, for now at least, and it's still in Beta. Beta means it has SLOs, which are like reliability goals, but it doesn

The other downsides are the deploys are slower, for now at least, and it's still in Beta. Beta means it has SLOs, which are like reliability goals, but it doesn't have SLAs, which means you get refunds for downtime. App Engine Standard does have SLAs: https://cloud.google.com/appengine/sla https://cloud.google.com/appengine/sla Beta products are also more willing to make backwards incompatible changes with shorter deprecation timelines. But overall it's certainly a lot more, ahem, flexible. Sneaky awesome feature is ability to install things like imagemagick , phantomjs, or ffmpeg, which to shamelessly self-promote I wrote about here: https://medium.com/google-cloud/scalable-video-transcoding-with-app-engine-flexible-621f6e7fdf56#.boyvfstt6 https://medium.com/google-cloud/scalable-video-transcoding-w... That's using a custom runtime, which won't be as officially blessed, but you can of course just extend from the official runtimes, since they're on Google Container Registry and open-source: https://github.com/GoogleCloudPlatform/python-runtime https://github.com/GoogleCloudPlatform/python-runtime Just write a Dockerfile that starts with: FROM gcr.io/google_appengine/python Obvious disclosure again I work for GCP.