Fly.io is amazing, I'm very excitied for it! They spin up a long-lived instance on the edge closest to the user and create a Wireguard tunnel in-between. They also have a free tier and reasonable pricing. Heroku is just far too expensive for a hobby project.

Usually the database (not the compute) is where things get expensive (Heroku's 10K rows is not practical for most tasks unless you're willing to do unholy things to put more data into a row).

I've written many lambdas in Python but have switched entirely to Go for all my new lambda work. Go is just better in every way - uses a fraction of the memory and executions take a tiny amount of the time Python takes.

I have a feeling AWS lambda's hypervisor has a lot of overhead, and simply making your workload smaller/lighter has a very noticeable reduction in execution time (cold start is <10ms on most of our GO lambdas).

re: full serverless:

I mean, try for yourselves but unless you're running an echo statement, you'll probably be hard pressed to get lower than this. Some early experiments with Rust showed 5x that, and that is as close to GO as I would dare to compare.

A while back I saw perf. tests on lambda cold starts per language. And somewhat surprisingly python was the fastest.

It's probably not the same test but python is still at the top [1]

[1] https://www.simform.com/blog/aws-lambda-performance/#Startup...