# Exercise: Your Toolkit, Version 1

Build the first version of your own toolkit, a file of aliases, two small functions and a prompt in your colors, answer four questions about startup files and installing tools, and let a check script try every shortcut for real.

Apprentice · Unix · Linux · Updated November 10, 2026

Every experienced terminal user has a toolkit: a file of short names and small helpers they've collected over the years and take to every computer they use. Today you start yours. Version 1 holds a better `ll`, a shortcut up one folder, an `rm` that asks first, two small functions, `mkcd` and `bak`, and a prompt in colors you choose. A check script loads your toolkit into a fresh shell, tries every shortcut for real, and tells you which ones work.

## Before you start

You need a terminal: the Terminal app on a Mac, or Ubuntu on Linux or in WSL on Windows. The check runs with **bats**, a small program that runs checks written for bash. If `bats --version` doesn't print a version number yet, install it:

```bash
sudo apt install bats       # Ubuntu, and Ubuntu in WSL
brew install bats-core      # a Mac, with Homebrew
```

`sudo` asks for your password, the one you use to sign in; nothing shows on the screen while you type it.

## Get the exercise code

Open this lesson's GitHub repository, [github.com/ask-codey/exercise-bash-your-toolkit-v1](https://github.com/ask-codey/exercise-bash-your-toolkit-v1), also linked from the **Exercise** box beside the lesson. Click **Code**, then **Download ZIP**, and unzip it into your `terminal-practice` folder. Or clone it with Git.

The folder holds:

- `toolkit/bash_aliases`: your toolkit, with one example done and six jobs to do, each a comment saying what to add.
- `answers.txt`: four questions about startup files and installing tools, each with a numbered line for your answer.
- `check.bats`: the check. You don't need to change it.

## What to do

Open a terminal and `cd` into the exercise folder, the one with `answers.txt` in it. Open the toolkit with `nano toolkit/bash_aliases`. Each job is a comment, with room under it for your lines:

```text
# Example: c clears the screen.
alias c='clear'

# 1. ll: a long list of a folder, hidden files included, with sizes such as 2.0K.
```

1. **`ll`**: a long list of a folder, hidden files included, with sizes such as `2.0K` (*Aliases and Small Functions*).
2. **`..`**: go up one folder.
3. **`rm`**: ask before deleting each file, the safer habit from *Deleting Safely: rm and rmdir*.
4. **`mkcd`**: a function that makes a folder, and any folders on the way to it, then goes into it. `mkcd "trip photos/day 1"` must work, spaces and all.
5. **`bak`**: a function that copies a file to the same name with `.bak` on the end, so `bak notes.txt` makes `notes.txt.bak`. It's the backup habit from *Startup Files: .bashrc, .zshrc and source*, in three letters.
6. **Your prompt**: a `PS1` with the folder you're in, at least one color, the color set back to normal, and `\$` at the end (*A Prompt in Your Colors*). The colors are your choice.

Save, then load the toolkit into the shell you're in and try each shortcut as you go: `source toolkit/bash_aliases`, then `ll`, then `mkcd test-folder`. Finally, answer the four questions in `answers.txt`, using *Startup Files: .bashrc, .zshrc and source* and *Installing Tools: Homebrew and apt*.

## Check your work

From the exercise folder:

```bash
bats check.bats
```

At first most checks fail. That's expected: each job you finish turns its check into a ✓. A failing check names the job and gives a hint, for example *There's no bak function in your toolkit yet. One line between { and } is enough: cp, the file, then the same name with .bak on the end.* The check works in a throwaway folder of its own, with a fresh bash that has loaded only your toolkit: it never reads or changes your own `~/.bashrc`.

## Hints

- **An alias error on loading?** `alias name = 'command'`, with spaces around the `=`, is the usual cause. The message names the line.
- **Spaces in a name** stay in one piece only when `$1` is in double quotes: `"$1"`. That goes for `mkcd` and for `bak`.
- **A function needs its braces:** `name() {` on the first line and `}` on the last.
- **Colors:** each code goes inside `\[` and `\]`, like `\[\e[1;36m\]`, and `\[\e[0m\]` sets the color back to normal. Try your prompt at the prompt first, then copy the line that you like into the toolkit.
- **On a Mac**, your Terminal runs zsh. The aliases and functions work there too, but the `PS1` line is bash's; the check runs it in bash.

## When you're done

Every check passes:

```text
check.bats
 ✓ the toolkit file is here
 ✓ the toolkit loads without errors
 ✓ 1) ll lists everything, with sizes people can read
 ✓ 2) .. goes up one folder
 ✓ 3) rm asks before deleting
 ✓ 4) mkcd makes a folder and goes into it
 ✓ 5) bak keeps a copy with .bak on the end
 ✓ 6) the prompt shows the folder, in color
 ✓ answer 1) the file bash reads when a terminal opens
 ✓ answer 2) the command that loads the toolkit into this shell
 ✓ answer 3) checking whether jq is installed
 ✓ answer 4) one command that installs all four tools

12 tests, 0 failures
```

Now make it yours for real. Copy the toolkit to `~/dotfiles/bash_aliases` and link it into place, as in *Your Dotfiles: A Setup You Can Carry*, and open a new terminal: your prompt and your shortcuts are there, and they will be in every terminal from now on. What would you add for version 2?

## Submit your exercise

The exercise is how you finish this lesson. When your work is done, put it on GitHub in a repo of your own, then submit that repo's address here.

1. On GitHub, click **+**, then **New repository**. Name it (for example `exercise-bash-your-toolkit-v1`), choose **Public**, and click **Create repository**. Leave out the README: your folder already has one.
2. In a terminal in your exercise folder (Ubuntu in WSL on Windows), send your work to your new repo. If you downloaded the ZIP:

   ```bash
   git init -b main
   git add .
   git commit -m "My solution"
   git remote add origin https://github.com/your-name/exercise-bash-your-toolkit-v1.git
   git push -u origin main
   ```

   If you cloned the starter instead, point your copy at your own repo, then commit and push:

   ```bash
   git remote set-url origin https://github.com/your-name/exercise-bash-your-toolkit-v1.git
   git add .
   git commit -m "My solution"
   git push -u origin main
   ```

3. Paste your repo's address, such as `https://github.com/your-name/exercise-bash-your-toolkit-v1`, into **Submit your exercise** on this page. The site checks that the repo is public and holds your commits, and then the lesson is complete.

Changed something after you submitted? Push it, and submit again: your latest submission is the one that counts.

## So what

A toolkit file is how working developers and administrators make any terminal feel like their own, and yours now has a first version you wrote, tested and can carry anywhere.

## Key terms

- [alias](https://www.ask-codey.com/glossary/alias-unix)
- [Shell Function](https://www.ask-codey.com/glossary/shell-function)
- [PS1](https://www.ask-codey.com/glossary/ps1)
- [source](https://www.ask-codey.com/glossary/source-unix)
- [.bashrc and .profile](https://www.ask-codey.com/glossary/bashrc-and-profile)
- [Package Manager](https://www.ask-codey.com/glossary/package-manager)

## Related

- [Aliases and Small Functions](https://www.ask-codey.com/lessons/bash-aliases-and-small-functions)
- [Startup Files: .bashrc, .zshrc and source](https://www.ask-codey.com/lessons/bash-startup-files)
- [A Prompt in Your Colors](https://www.ask-codey.com/lessons/bash-custom-prompt)
- [Installing Tools: Homebrew and apt](https://www.ask-codey.com/lessons/bash-installing-tools)
- [Your Dotfiles: A Setup You Can Carry](https://www.ask-codey.com/lessons/bash-dotfiles)

Source: https://www.ask-codey.com/lessons/exercise-bash-your-toolkit-v1