Tap the keg:
brew tap nhemsley/homebrew-env https://github.com/nhemsley/homebrew-env.git
Install:
brew install homebrew-env
Cache the shellenv:
brew env recache
Put this in ~/.bashrc OR ~/.profile etc.
. $(brew env source-file)
Show the shellenv
brew env shellenv
Edit $HOMEBREW_PREFIX/etc/brew-env/presets.yaml to create/change environment scripts.
They key is the same as the brew installed package name.
Not hard.
PR's welcome for presets.yaml updates, and anything else.