import-env is a tiny, dependency-free Ruby tool that lets you run any shell script, capture the environment variables it adds/changes/removes, and print a Bash snippet that reproduces those changes in the current shell. Think of it as direnv’s “env diff” algorithm, but standalone and shell-agnostic.

mkdir ~/.local/bin
curl -o ~/.local/bin/import-env https://raw.githubusercontent.com/zah/import-env/main/bin/import-env
chmod +x ~/.local/bin/import-env

Requires Ruby ≥ 2.3 (present on macOS and most Linux distros).

# bring variables from setup-env.sh into the live shell
eval "$(import-env ./setup-env.sh --debug)"

# run a command with that environment, without touching the caller
bash -c "$(import-env ./java-env.fish); exec mvn test"

Inside a Bash script:

#!/usr/bin/env bash
set -euo pipefail
eval "$(envdiff ./bootstrap.zsh)"
# …PATH, JAVA_HOME, etc. are now set…

sh, bash, zsh, dash, ksh, fish If the script’s she-bang names anything else, import-env exits with status 2 and a clear message.

MIT © 2025 Zahary Karadjov