You don't have to import everything just to print the help. I try to avoid top-level imports until after the CLI arguments have been parsed, so the only import until then is `argparse` or `click`. This way, startup appears to be instant even in Python.

Example:

    if __name__ == "__main__":
        from myapp.cli import parse_args

        args = parse_args()

        # The program will exit here if `-h` is given

        # Now do the heavy imports

        from myapp.lib import run_app

        run_app(args)

The Python startup latency thing makes sense, but I really don't understand why it would take `pyenv` a long time to print each line of its "usage" output (the one that appears when invoking it with `--help`) once it's already clearly in the code branch that does only that.

It feels like like it's doing heavy work between each line printed! I don't know any other cli tool doing that either.

Not to derail the Python speed hate train but pyenv is written in bash.

It's a tool for installing different versions of Python, it would be weird for it to assume it already had one available.

The "slowness" and the utter insanity of trying to make a "works on my computer" Python program work on another computer pushed me to just rewrite all my Python stuff in Go.

About 95% of my Python utilities are now Go binaries cross-compiled to whatever env they're running in. The few remaining ones use (API) libraries that aren't available for Go or aren't mature enough for me to trust them yet.