- It requires discipline for devs to keep the conf declarative. Discipline is not automatically enforceable, so it's prone to failure.

- No guarantee of reproducibility.

- You need a Python VM (or a starlark interpreter if that's what you like). It's a big constrain.

- If you are a Saas provider, accepting Python as input is really hard to secure.

- throw an exception

- crash or segfault

- accept malformed input

- produce malformed output

- hang or time out

in https://docs.dhall-lang.org/discussions/Safety-guarantees.ht...

Still a fan of Python for configuration?