Need tech stack suggestion

Need tech stack suggestion

Tech stack for Mocsh was Java, Springboot and Postgres.

As I prepare to re-imagine and rebuild it, looking for help to identify a good stack. I want to consciously stay away from Typescript / Javascript / Node on the server.

The problem statement is simple:

• HTTP API
• Database persistence
• HTTP and IMAP Client to access emails
• Rule engine / ML engine to identify / tag

Here are starting points that come to mind:

• Rust
• Go
• Ruby on Rails
• Java / Kotlin
• Swift

With Postgres / Mongo / MariaDB

I want to use Docker Compoae / Kubernetes as the deployment stack. And Digital Ocean as the hosting platform.

Recommendations ?