bem — Bash Extension Manager

A secure, lightweight tool for managing shell scripts as commands.

Install

One command (clones to ~/.local/share/bem by default):

bash <(curl -fsSL https://raw.githubusercontent.com/<user>/bem/main/install.sh)
exec bash

With bundled plugins (search, replace):

bash <(curl -fsSL ...) --full

Custom location — bem can live wherever you want:

bash <(curl -fsSL ...) -d ~/my-tools/bem --full

Manual (clone wherever you want, run init):

git clone https://github.com/<user>/bem.git ~/wherever/you/want
cd ~/wherever/you/want
./bem init
./bem install plugins/search plugins/replace   # optional
exec bash

bem init creates a symlink ~/.local/bin/bem -> <wherever bem lives>. Everything else is managed from there. There is no hardcoded install path.

How It Works

bem creates symlinks in ~/.local/bin/ pointing to your scripts. No aliases, no eval, no sourced plugin code. The only file sourced in .bashrc is a ~1.8KB autocomplete function.

~/.local/bin/
├── bem     -> ~/wherever/bem                 (bem itself)
├── search  -> ~/wherever/plugins/search      (plugin)
└── replace -> /some/other/path/replace       (plugin from anywhere)

Plugin metadata lives in ~/.bem/plugins/<n>/{enabled, path, repo}.

Commands

Lifecycle

Command	Description
bem init	Initialize. Creates symlink for bem, sets up autocomplete.
bem install [-n <n>] <file> ...	Install scripts as plugins.
bem remove <name ...>	Unregister plugins. Original files are kept.
bem purge <name ...>	Unregister AND delete original files.
bem uninstall	Remove bem completely. Double confirmation.

Control

Command	Description
bem enable <name ...>	Create symlink (activate).
bem disable <name ...>	Remove symlink (deactivate).

Info

Command	Description
bem list	Show all plugins with status.
bem status <name ...>	Detailed info: file integrity, symlink, permissions.
bem help [name ...]	Plugin docs or usage message.
bem version	Show version.

Updates

Command	Description
bem update <name ...>	Git-pull specific plugins.
bem update-all	Git-pull all git-tracked plugins.
bem upgradeable	Check for available updates (fetch only).
bem self-update	Update bem itself.

All destructive commands (remove, purge, uninstall) require confirmation. There is no force flag.

Bundled Plugins

search

Fast file and content search. Literal strings, no regex.

search main                    # find files by name
search -c 'TODO' -e py         # content search in .py files
search -c -i --color error     # case-insensitive
search -o main                 # open first match in $EDITOR

replace

Safe recursive find-and-replace. Literal strings only.

replace foo bar ./src
replace '$PRICE' '€100' ./templates
replace 'C:\old' 'C:\new' ./configs
replace -N --color 'cout' 'print' .    # dry run
replace -e js 'var ' 'const ' ./src    # extension filter

External Plugins

Any executable on your system can be a plugin:

git clone https://github.com/someone/tool.git ~/tools/tool
bem install -n mytool ~/tools/tool/script.sh
bem update mytool       # git pull (auto-detected)
bem upgradeable         # check for new versions

Security

See SECURITY.md for the full review.

Key points: zero aliases (everything is a symlink), ~1.8KB fixed sourced code, 100+ reserved command names, mandatory confirmation on destructive ops, umask 077, atomic writes, flock concurrency control, --ff-only git pulls, world-writable detection.

Directory Layout

~/wherever/bem/              (the git repo — lives anywhere you want)
├── bem
├── plugins/{search,replace}
├── install.sh
├── SECURITY.md
└── README.md

~/.bem/                      (runtime metadata — managed by bem)
├── bem_source.bash          (autocomplete only, ~1.8KB, read-only)
├── .lock
└── plugins/<n>/{enabled,path,repo}

~/.local/bin/                (symlinks — the commands)
├── bem -> ~/wherever/bem/bem
└── <n> -> /path/to/script

Requirements

• Bash 4.0+
• find, grep, flock, realpath, stat, ln
• perl (for the replace plugin)
• git (for updates)

Uninstall

bem uninstall
exec bash

License

MIT