Running command on file changes

There is a lot of tools to run some command when a file is edited, with various levels of completeness and complication

watchexec seems like a good balance.

For example, to execute cargo run when things change (restart the process if it's still running):

watchexec -r -- cargo run

It also works with shell commands like

watchexec -r -- 'cargo run && python -m http.server --directory _generated'

Found it from this article, which also describes a more elabourate setup which handles socket connections better.