The Missing Bit

Useful UNIX commands

This is my list of less known but great UNIX command I use daily.

It’s mostly focused on development rather than sysadmin.


Super fast code search (grep on steroids).

$ ag ster
73:Super fast code search (`grep` on steroids).

It will save you from the end of the world.


Renders a folders and files hierarchy.



$ tree
├── Gemfile
├── Gemfile.lock
├── Rakefile
├── _config.yml
├── _drafts
│   ├──
│   ├──
│   └──
├── _includes
│   ├── footer.html
│   ├── head.html
│   └── header.html
├── _layouts
│   ├── default.html
│   ├── page.html
│   └── post.html

On macOS, you can install it with hombrew.


Allows to have a local environment.

For example, if you put:

export MY_SECRET=hello

in a .envrc file, as soon as you cd <folder_containing_envrc> MY_SECRET will be defined to hello .

Super handy to manage app secrets.


Will display a tree of processes.

pstree -g 3 -w | less

Under FreeBSD, ps has a built in similar functionality:

ps -auxd | less

Piping into less is of course optional, but less is more.