I have a Prisma Fargate instance running and it works great. One thing I'm wondering is why there are two VPCs. Would a PR that put the db and the server into one VPC, with public/private subnets be appreciated or is there something I'm missing here?

I think you are talking about https://github.com/prismagraphql/prisma-templates, right? Could you please create an issue first so we can discuss this before you submit a PR? 🙂

Sensible idea. Issue is here: https://github.com/prismagraphql/prisma-templates/issues/9. It would also affect this repo: https://github.com/prismagraphql/database-templates/blob/master/aws/mysql.yml