kai.dev 📓

Effort Is All You Need

2025-07-12T00:00:00Z

The year 2025 is an interesting time to be a software engineer. For better or worse, GenAI continues to disrupt, in all of its equally beneficial and harmful ways that I've both witnessed and can foresee. I'm left with conflicting feelings about AI in general that range from optimism to pessimism and everything in-between. How I personally feel about it doesn't really matter, though. The industry has embraced GenAI and in order for me to compete and stay relevant, I need to elevate my craft and expand my toolbelt to stay on top of my game. This is the case with GenAI, and it will be the case after the next disruption. I already know this. So why haven't I yet?

While I have worked on a few experimental GenAI projects internally at Spotify, I did so because I had to. Sure, it was cool and interesting and new, but I haven't done much outside of that in my own time. I read into that as a measurement of my interest; if something is not a hobby of mine, I must not be interested 🤷🏾. But I am interested and I do want to learn more. I know this because I think about it daily, but what I don't do daily is take action. After an honest conversation with myself, the truth is I've been stagnant and lazy, often putting blame on my lack of free time. And while free time is much more limited these days, unless I become wealthy and retire tomorrow, the time constraint ain't going anywhere, fam. Not until I do something about it. I have way too many privileges to be complaining about time.

Here are three actions I'm already taking:

Therapy. I can get in my own way unconsciously through poor habits. I need an expert with an unbiased perspective, opinion, and no attachments, to tell me the things I won't or am too afraid to tell myself.
This blog. This will be an outlet for me to share thoughts and talk tech. It's also a public space to hold myself accountable, so I'm not just talking BS.
Effort. Consciously put forth a focused effort into everything that I care about. Such as my relationships with God, my family, my craft, and most importantly myself.

While I'm here on this topic, I want to give a special shout out and thank you to my beautiful wife, Makeda, for all of your unconditional love and support 😘. You've always been right by my side, pushing and supporting me to be the best version of myself. Pushing me to create content, encouraging me to share my knowledge from my perspective, because you believe in me and my abilities. Thank you, I love you!

Okay, so I started this post talking about GenAI 😅. To get to the standard of understanding that my brain needs to be happy, I need to learn and understand not only how to use it, but also how it works under the hood, so that I can have the intuition to manipulate it, make practical use of it in any context, and hack around it when I need to get creative. This learning process will be fun, enlightening, boring, full of mistakes, and frustrating at times. It will be a grind. So be it. Stay tuned as I document this journey, among other things.

Relevant Music

This is one of my favorite songs by Big Sean. I feel like it captures the vibe of this post.

Follow the PATH, Part I: Basics

2025-08-03T00:00:00Z

Any time you type a command in your terminal, your shell will try to locate that command on the filesystem. If found, your shell will run the command. Otherwise, you’ll typically see a “command not found” error or similar. You already know this.

But where exactly is your shell looking for the command? It searches the "list" of the directories specified in your PATH environment variable:

> echo $PATH
/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin

In the example above, you probably noticed that the "list" is actually a long string of colon-delimited directories. This is commonly referred to as the "search path." Your shell will search each directory, in the order that they’re specified, stopping as soon as it finds the command you're attempting to run.

This process is what makes it possible to have multiple versions of the same program installed, such as python3. For example, macOS Tahoe ships with Python 3.9 pre-installed to /usr/bin/python3. But I want to use Python 3.12, so I use my favorite package manager, Homebrew, to brew install python@3.12. This leaves me with two versions of python3 on my system:

/usr/bin/python3
/opt/homebrew/bin/python3

Which one will run when I type python3? You can find out using the which command:

> which python3
/usr/bin/python3

The outdated, pre-installed version will run because /usr/bin appears in my search path, and /opt/homebrew/bin is not present at all, as seen above in my PATH output.

To workaround this, you could type the full, absolute path to the newer version:

> /opt/homebrew/bin/python3
Python 3.13.5 (main, Jun 11 2025, 15:36:57) [Clang 17.0.0 (clang-1700.0.13.3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>

The more idiomatic approach is to modify your PATH environment variable so that /opt/homebrew/bin is also in the search path. It's also important to ensure that it appears sooner than /usr/bin, so that your shell looks there first:

export PATH="/opt/homebrew/bin:$PATH"

This takes the existing PATH value and prepends it with /opt/homebrew/bin, before assigning the new value back to PATH. The export directive makes the updated PATH value available in any child processes or subshells.

> export PATH="/opt/homebrew/bin:$PATH"

> echo $PATH
/opt/homebrew/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin

> which python3
/opt/homebrew/bin/python3

Manually typing it like this is a one-off override for your current shell session only. To persist it so that you don't need to do this again, put export PATH=... in your shell configuration file, such as .bashrc, .zshrc, or similar depending on which shell you use.

Get familiar and comfortable with checking and manipulating your PATH. Over time, as you install things, your search path will get messy and it's inevitable that at some point you'll need to go in and fix it yourself.

`echo` vs `printenv`

`echo`

To see the value of PATH or any environment variable, most people typically use echo:

> echo $PATH

/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin

When using this method, the dollar sign is a special character that tells your shell to replace $PATH with its literal value. That literal value is then passed as an argument to echo. As its name implies, echo simply outputs or echos whatever you pass to it.

One gotcha is that echo always returns 0 , even if the environment variable doesn’t exist, because echoing nothing is a still valid operation for echo.

> echo $BLAH

> echo $?
0

In the example above, I used $? to output the return/exit code of the last command. Zero means success, non-zero means failure.

Still, using echo is completely fine for quickly inspecting environment variables.

`printenv`

If you need the value of an environment variable and you want to validate that there wasn’t an error retrieving it, such as when writing scripts for automation, I would encourage you to use printenv instead:

> printenv PATH
/opt/homebrew/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin

> echo $?
0

There is no dollar sign, so nothing will be replaced. We are passing the literal string “PATH” to the command printenv. It will then check that the variable exists (case-sensitive), and if so, returns its value. If not, there will be no output and the return code will be 1, indicating an error retrieving the value.

> printenv BLAH

> echo $?
1

NOTE: One important caveat is that printenv can only display environment variables and exported variables. To output local variables, you need to use echo. Some might consider printenv to be "safer" when you're checking specifically for environment variables. There are other ways to test for values using conditionals expressions, however, they are similar to echo in that they can't distinguish between local and environment/exported variables.

On Using GenAI to Manage Your PATH

Don't. No matter how good you think your GenAI utility is at managing your shell configuration files, you need to understand how the PATH works and how to fix it yourself. After you install enough programs, your PATH will become messy and contribute to producing unexpected results at some point. No developer can avoid this with GenAI; it's a human cost. So don't waste your requests/tokens repairing something that you can easily repair yourself. Lastly, you haven't even seen the PATH's final form (spoiler: I'll cover Python's virtual environments in the third post of this series 🙂).

Relevant Music

You can't avoid the human cost that must be paid. Learn the fundamentals, follow the PATH, be more productive.

Follow the PATH, Part 2: Jump Around

2025-08-04T00:00:00Z

We're all familiar with using the cd command to jump around directories. Normally you need to know and type either an absolute path or a relative directory name when using cd, except for common shortcuts like:

> cd
/Users/kai

> cd ./code
/Users/kai/code

> cd ..
/Users/kai

> cd -
/Users/kai/code

In the above examples, we jumped $HOME (aka ~) by providing no arguments, then into an adjacent directory, into the parent directory, and back into the last directory, respectively. What I've seen most people do in practice is either manually type most of the path/directory, and then rely on tab completion to cycle through and finish, or they create aliases to use a single command as a shortcut to jump to their favorite directory:

> alias c="cd ~/code"

> c
/Users/kai/code

These all work, but if you're like me, you have a hundred directories worth of projects that you navigate in and out of.

`CDPATH`

CDPATH works similar to PATH in that you provide a comma-delimited list of directories that become the search path for the cd command. Let's look at a practical example to understand the benefits. For this example, assume I keep my projects organized in /Users/kai/code:

~/code
❯ tree
.
├── alpha
├── beta
├── charlie
├── delta
├── echo
├── foxtrot
├── golf
└── hotel

9 directories, 0 files

I can use CDPATH to set ~/code as a search path for cd:

export CDPATH=~/code

With this set, I can now type cd golf, from anywhere, and cd will utilize the search path to look for matching subdirectory names in each of the top-level directories that I provided to CDPATH.

Gotcha

In almost all cases, you will want the first directory in your CDPATH to be the current directory (aka .) so that you can continue to cd into relative directories:

export CDPATH=.:~/code

Now, if I have a subdirectory named golf in my current working directory, I will cd into the relative path, ./golf, rather than /Users/kai/code/golf. But what if I preferred to go to the latter? The next section has the answer.

Zoxide (Recommended)

Now that you have intuition into how search paths work, I trust that you can fix PATH issues yourself. Also, you don't actually need to use CDPATH directly because there is a more productive solution.

Zoxide provides the same jumpability benefit as CDPATH and adds quality of life improvements such as completions, duplicate directory name resolution, and automatic directory tracking so that you don't ever need to manage any environment variables yourself.

Install zoxide and its dependency fzf, then add the initialization script to your shell config and reload your shell:

> brew install zoxide fzf
...
🍺  /opt/homebrew/Cellar/zoxide/0.9.8: 18 files, 1MB
...
🍺  /opt/homebrew/Cellar/fzf/0.65.1: 19 files, 4.5MB
...

> echo 'eval "$(zoxide init zsh)"' >> ~/.zshrc

> exec zsh

Now, from this point forward, use z instead of cd. Zoxide will remember where to jump around to, so that you can recall later even faster. Example:

> z golf
zoxide: no match found

> z ~/code/golf
/Users/kai/code/golf

> z
/Users/kai

> z golf
/Users/kai/code/golf

Since installing Zoxide, I haven't jumped to ~/code/golf before, so using z golf found no matches. After I z into the directory myself, Zoxide knows where I've been, enabling me to jump back from anywhere via z golf, or even with a partial word match like z go. Eventually using something really short like z go can become ambiguous once you visit any other directories that start with or contain go. When path matches become similar, Space+Tab to resolve.

Here's a short animated demo, that I lifted directly from the official Zoxide GitHub repo.

Relevant Music

Only one song makes sense here. 😅

kai.dev 📓

Effort Is All You Need

Relevant Music

Follow the PATH, Part I: Basics

echo vs printenv

echo

printenv

On Using GenAI to Manage Your PATH

Relevant Music

Follow the PATH, Part 2: Jump Around

CDPATH

Gotcha

Zoxide (Recommended)

Relevant Music

`echo` vs `printenv`

`echo`

`printenv`

`CDPATH`