macOS Ruby Environment Reset Script

Version: 2.6.0
Supported OS: macOS only (Darwin)
Shell Compatibility: Bash 3.2+ (default on macOS)

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TL;DR

This script resets your Ruby environment to the default system Ruby on macOS. It:

• Detects and attempts to remove version managers (rbenv, rvm, asdf)
• Removes all non-system Ruby versions and associated gems
• Cleans up shell init files and lingering Ruby paths
• Removes .ruby-version / .tool-versions files
• Cleans stale Homebrew taps (optional)
• Provides a post-run audit with instructions if anything remains

⚠️ This script is for macOS only. Running it on other systems may break your Ruby environment.

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Quick Examples

Interactive cleanup

bash ./reset-macruby.sh

• Lists detected managers and Ruby installs
• Prompts before removal

Full automation

bash ./reset-macruby.sh --full-reset

• Removes all Ruby installs, managers, gems, caches, and shell init entries
• Cleans Homebrew stale taps
• Shows post-run audit

Skip removing version managers

bash ./reset-macruby.sh --full-reset --keep-managers

• Resets Ruby versions and gems but keeps rbenv, rvm, and asdf

Dry run (preview actions)

bash ./reset-macruby.sh --dry-run

• Shows exactly what would happen without making changes

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Flags

Flag	Description
--dry-run	Show what actions would be taken without making changes
--full-reset	Remove all detected Ruby installs, attempt to remove managers, scrub shell files, clear caches, purge .ruby-version files, and untap stale Homebrew repos
--keep-managers	Skip removal of rbenv, rvm, and asdf even if detected
--purge-ruby-version	Automatically remove .ruby-version files without prompting

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Post-Run Audit

After running, the script will show:

• Remaining version managers
• Their locations and binary paths
• Shell init file references
• Exact manual removal steps

Example:

⚠️  rbenv still detected:
   • binary on PATH: /opt/homebrew/bin/rbenv
   • Homebrew formula: rbenv (installed)
   • user directory: /Users/alex/.rbenv
   • init lines in:
     /Users/alex/.zprofile:8:eval "$(rbenv init - --no-rehash zsh)"
   → Suggested removal steps:
     - brew uninstall rbenv ruby-build
     - rm -rf "/Users/alex/.rbenv"
     - sed -i '' -E '#rbenv#d' ~/.zshrc ~/.zprofile ~/.bashrc ~/.bash_profile
     - sed -i '' -E '#/\.rbenv/shims#d' ~/.zshrc ~/.zprofile ~/.bashrc ~/.bash_profile
     - exec $SHELL

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What This Script Removes

• Ruby installs: rbenv, rvm, asdf, Homebrew, standalone
• Gem caches: ~/.gem, ~/.bundle, ~/.cache/bundler, ~/.rvm/gems, ~/.rvm/gemsets, ~/Library/Caches/ruby-build
• Manager directories: ~/.rbenv, ~/.rvm, ~/.asdf
• Homebrew packages: rbenv, ruby-build, asdf
• Shell init lines referencing managers
• .ruby-version and .tool-versions entries

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Notes

• Always restart your shell or run exec $SHELL after changes
• To check your Ruby version after reset:

which ruby && ruby -v

• You should see /usr/bin/ruby for macOS system Ruby