Of course if they were using GCE, GKE, or any other way to deploy compute they'd be fine. In this case, because they're using GAE, they have limited language support without doing lots of (to them) complex stuff.

It's the right decision to port here.

> When I looked at the code, I realized I was not going to be able to reuse anything because it was written in Perl. My plan was to rely on many of Google’s managed services, which don’t support Perl.

I didn't know Google did shared hosting these days (like, PHP or whatever they do support, I knew about VPSes and hosted databases).