Configure carapace to run a command to generate completions for a given command

[b0o]

Some programs have a CLI flag/subcommand that can be used to generate shell completions. They often tell you to add it to your shell like eval $(someprog --shell-completions) or similar. In the interest of shell startup time, sometimes this isn't desirable. Is there a way to configure carapace to tell it that this is how to get the completions for a command, and for it to run it on-demand when the user requests completions?

[b0o]

I suppose the solution is to create ~/.config/carapace/bridge/bash/.bashrc and add eval "$(myprog --shell-completions)", then add myprog: bash to ~/.config/carapace/bridges.yaml.

I wish the docs were a bit easier to follow and had more examples.