pyenv-python

A pyenv shim for python that's much faster than pyenv.

Usage

This python shim, i.e., $CARGO_HOME/bin/python, loads much faster than pyenv's python shim, which is written in Bash.

This helps a lot when running CLI scripts in Python, since the time is takes to run the CLI script is often less than the time it takes pyenv to find python.

For example, with starship, python --version is run every time when you're in a Python directory to display the current Python version on the prompt, but if pyenv's python shim takes ~1 sec, it makes the prompt painfully slow. Using this python shim, the time for python --version is unnoticeable.

Performance

On my local computer, $CARGO_HOME/bin/python --version runs about 10x faster than $PYENV_ROOT/shims/python --version.

``` workspace/misc/pyenv-python-test via 🐍 v3.5.9 took 19s ❯ hyperfine '$CARGOHOME/bin/python --version' Benchmark #1: $CARGOHOME/bin/python --version Time (mean ± σ): 65.3 ms ± 5.8 ms [User: 1.8 ms, System: 56.7 ms] Range (min … max): 57.6 ms … 85.8 ms 32 runs

workspace/misc/pyenv-python-test via 🐍 v3.5.9 took 21s ❯ hyperfine '$PYENVROOT/shims/python --version' Benchmark #1: $PYENVROOT/shims/python --version Time (mean ± σ): 715.3 ms ± 164.2 ms [User: 57.3 ms, System: 649.7 ms] Range (min … max): 593.1 ms … 1055.0 ms 10 runs ```

Installation

It's just published to crates.io, so you need cargo from rustup to install.

Then cargo install pyenv-python will install python and python-path. For this python to wrap the pyenv python or the system python, it $CARGO_HOME/bin must be before any other pythons in $PATH.