direnv
is a manager for loading/unloading environment
variables per-project. It achieves this by hooking into your shell and
executing a shellscript called .envrc
upon cd
, loading environment
variables generated by that shellscript into your current shell. It is useful
for automatically activating
virtualenvs, for example.
Unfortunately direnv
can be a little bit "intrusive" to use. For a start, it
runs its own code in your shell. This alone is not noticeable in terms of
terminal responsiveness, but the various .envrc
s that people end up writing
sometimes are. direnv
does not have a reliable, out-of-the-box way to cache
the execution of .envrc
s, as it is arbitrary code, and so it runs everytime
you cd
in and out of a project.
quickenv
is a replacement for direnv
. It works with existing .envrc
s, and
as such is a drop-in replacement, but how you interact with quickenv
and how
it loads environment variables is fundamentally different.
quickenv
does not hook into your shell. It only requires an addition to yourPATH
.quickenv
does not load.envrc
when changing directories. Instead you need to initializequickenv
per-project usingquickenv reload
, and rerun that command everytime the.envrc
changes.quickenv
does not even load environment variables into your shell. Instead it creates shim binaries that dispatch to the right executable.
quickenv
is heavily inspired by volta which achieves
version management for nodejs by also providing "shim" binaries for the most
common commands (yarn
, npm
, node
).
quickenv is work in progress. that said, I use it daily at work
Download the latest binary and:
# Into your bashrc/zshrc. This should be at the front of your PATH, such that
# quickenv can shim/shadow binaries effectively.
export PATH=$HOME/.quickenv/bin/:$PATH
# You can remove "direnv hook" from your bashrc/zshrc, but the tool needs to
# stay installed.
Some notes:
-
quickenv
currently assumesdirenv
is in your path, in order to load its "standard library". -
quickenv
also currently does not have pre-built binaries. You need to install Rust and install it using Rust's package manager, Cargo. -
quickenv
assumes a POSIX environment.
cargo install quickenv # latest stable release
cargo install --git https://github.com/untitaker/quickenv # latest git SHA
We're going to check out sentry, because
that's one of the .envrc
s I use. Note that Sentry's .envrc
only works on
MacOS.
git clone https://github.com/getsentry/sentry
cd sentry
# Execute the .envrc and cache the resulting environment variables in ~/.quickenv/envs/.
# Sentry will prompt you to create a virtualenv, install dependencies via homebrew, etc.
# Re-run this command manually everytime the .envrc changes.
quickenv reload
# As part of executing the .envrc, a virtualenv has been created at './.venv/'.
# There are multiple commands available in '.venv/bin/', such as 'pytest' (a test
# runner), or 'sentry' (the main application).
# 'quickenv shim' makes those commands available in your shell.
quickenv shim
# These commands will now run with the virtualenv enabled.
sentry devserver --workers
pytest tests/sentry/
# Alternatively you can shim commands explicitly. Be careful: Any command you
# missed (such as 'python' or 'pip') would run outside of the virtualenv!
quickenv shim sentry pytest
# You can also run commands within the current .envrc without shimming them.
quickenv exec -- pytest
# Your git hooks don't execute in the virtualenv for some reason? Just replace
# git with a binary that itself loads the virtualenv.
quickenv shim git
# Actually activate the virtualenv in your current shell. `quickenv vars`
# prints all the extra environment variables with which each shimmed binary runs.
set -o allexport
eval "$(quickenv vars)"
set +o allexport
# Or alternatively, substitute your shell with one where your .envrc is loaded
exec quickenv exec $SHELL
# Or shim 'bash', so that when you open a subshell, the virtualenv is activated.
quickenv shim bash
# Or shim 'make', so your Makefile runs in the virtualenv.
quickenv shim make
# Curious which binary is actually being executed?
quickenv which make
# /home/user/.quickenv/bin/make
# Or for general debugging, increase the log level:
QUICKENV_LOG=debug make
# [DEBUG quickenv] argv[0] is "make"
# [DEBUG quickenv] attempting to launch shim
# [DEBUG quickenv] abspath of self is /home/user/.quickenv/bin/make
# [DEBUG quickenv] removing own entry from PATH: /home/user/.quickenv/bin
# [DEBUG quickenv] execvp /usr/bin/make
# ...
Licensed under MIT
, see LICENSE
.