Comment That Saved Christmas
(And My Sanity)

Why Documentation is a Love Letter to Future You

Ken Mendoza Programming Musings Oregon Coast AI

" best code comments aren't just explanations—they're time capsules of empathy, messages in bottles thrown forward to developer who will inevitably be you."

It was December 23rd, 2019. I was supposed to be wrapping presents and prepping for Christmas morning with Toni, but instead I was staring at my laptop screen in our cozy Waldport office, watching our client's e-commerce platform crash spectacularly during their biggest sales day of year.

Christmas Eve Emergency

call came in at 9:47 PM. Their payment processing system had gone down, and with it, thousands of last-minute Christmas shoppers were stuck with full carts and error messages. original developer had left company six months earlier, and I was only one who could dive into codebase.

$47K
Lost sales per hour
2,300
Abandoned carts
16 hrs
Until Christmas

My ADHD brain was firing on all cylinders—part panic, part hyperfocus. I dove into payment processing module, a labyrinth of functions that handled credit card validation, fraud detection, and transaction routing. error logs were cryptic, pointing to a function called processSecurePayment() that was mysteriously returning null for all transactions.

You know that feeling when you're debugging someone else's code at 10 PM on Christmas Eve?

Every variable name is a cryptic abbreviation

logic flow jumps around like a caffeinated seagull

You're questioning every life decision that led you to this moment

I was three hours deep, my coffee had gone cold twice, and Toni had already given up on me joining her for our traditional Christmas Eve movie. payment system was a house of cards, and I couldn't figure out which card was causing collapse. Functions called other functions that called other functions, each one more mysterious than last.

Then I Found It: Comment That Changed Everything

Buried 300 lines deep in a seemingly unrelated authentication module, there it was— not just any comment, but a perfect little love letter from past developer to future developer.

/** * CRITICAL: This function validates payment tokens but has a sneaky dependency * on timezone offset calculation in utils/dateHelpers.js * * WHY THIS MATTERS: When daylight saving time ends (Nov 1st) or begins (March), * token expiration logic gets confused and treats all tokens as expired. * * DEBUGGING TIP: If payments are mysteriously failing en masse, check if * we just had a DST transition. fix is in line 847 of dateHelpers.js * * TESTED: This burned us during Black Friday 2018. Never again. * * - Sarah M., October 2019 * * P.S. - Future developer, I'm sorry you're probably debugging this at 2 AM. * There's emergency coffee in office kitchen. You've got this! ☕ */

I literally laughed out loud in my empty office. Not only had Sarah predicted my exact situation (down to late-night debugging), but she'd given me precise location of fix. I navigated to utils/dateHelpers.js, line 847, and there it was—a daylight saving time bug that was causing all payment tokens to be treated as expired.

Fix That Saved Christmas

One line change. Literally one line. I updated timezone offset calculation to properly handle recent daylight saving transition, deployed fix, and watched as payment success rate went from 0% to 98% in real time.

- const offset = date.getTimezoneOffset() * 60000;
+ const offset = (date.getTimezoneOffset() + getDSTOffset(date)) * 60000;

By 1:30 AM, client's sales were flowing again. Christmas was saved. But more importantly, I had learned something profound about art of documentation that would change how I approach every line of code I write.

What Sarah's Comment Taught Me About Code Empathy

That comment wasn't just documentation—it was empathy encoded in text. Sarah had imagined future developer (me) in distress, anticipated my needs, and provided not just technical solution but emotional support. She had written for human being, not just computer.

Bad Comments

// increment counter
counter++;
// TODO: fix this later
// this is complicated

Empathetic Comments

// Counter tracks failed login attempts
// Reset to 0 after successful auth
counter++;
// TODO: Extract to config file
// Hardcoded for MVP, issue #247
// Complex timezone math ahead
// See RFC 3339 for date formats

Four Pillars of Empathetic Documentation

Context: Why does this code exist? What problem does it solve?
Gotchas: What non-obvious things could go wrong?
Breadcrumbs: Where should next developer look if something breaks?
Humanity: Acknowledge that debugging is hard and reader is trying their best

My ADHD brain loves patterns, and I started to see documentation as a pattern of care. Every well-written comment is a tiny act of service to a future developer—often yourself, but three months later when you've forgotten everything about why you made that weird architectural decision.

My New Documentation Philosophy

After that Christmas Eve revelation, I started thinking of comments as lighthouse beams—they should illuminate dangerous waters ahead and guide travelers safely to shore.

Every time I write a comment now, I imagine myself six months from now, tired and debugging at 11 PM, desperately needing a friend in code to show me way.

Real Examples from My Current Projects

/**
* AI model inference endpoint - handles both text and image inputs
*
* PERFORMANCE NOTE: This function can take 2-15 seconds depending on model size
* Always call with a timeout wrapper (see utils/withTimeout.js)
*
* MEMORY GOTCHA: Large images (>5MB) can cause OOM errors
* Preprocess in imageUtils.resizeForInference() first
*
* DEBUGGING: If you get "model not found" errors, check:
* 1. MODEL_PATH environment variable
* 2. models/ directory has proper permissions
* 3. Hugging Face cache isn't corrupted (rm -rf ~/.cache/huggingface)
*
* Fun fact: This comment is longer than function. Worth it. 🤖
*/
async function runInference(input, modelName) {

Why this works: Future me knows exactly what could go wrong and where to look.

/**
* Beach weather data fetcher for our coastal AI models
*
* This feels over-engineered, but Oregon coast weather is WEIRD:
* - Microclimates change every mile
* - API data lags reality by 20+ minutes
* - Wind direction affects our solar panel efficiency
*
* retries and caching aren't paranoia—they're survival.
*
* Love, Past Ken (who debugged this during a windstorm) 🌊
*/
const fetchCoastalWeather = async (location) => {

Why this works: I explain "why" behind seemingly excessive complexity.

beautiful thing about empathetic documentation is that it makes you a better programmer, not just a better commenter. When you force yourself to explain complex logic in human terms, you often discover simpler solutions. When you anticipate edge cases for documentation, you catch bugs before they happen.

Ripple Effect of Compassionate Code

That Christmas Eve emergency taught me that documentation is fundamentally about relationship building. Every comment is a conversation across time between developers. When we write with empathy, we create a culture of care that spreads through our teams and our codebases.

Unexpected Benefits

Team trust increases when people know their code will be maintainable

Code reviews become collaborative instead of adversarial

New team members onboard faster with well-documented codebases

Technical debt decreases because problems are explained, not just patched

You sleep better knowing your code won't cause 2 AM emergencies

These days, when I'm deep in a coding session here in Waldport, listening to ocean waves and working on our latest AI models, I think about Sarah's comment every time I write documentation. She didn't just solve my immediate problem—she modeled a way of being in world of software development.

" best legacy code isn't code that runs forever—it's code that can be understood, modified, and loved by humans who come after us."

— Lessons from Oregon Coast

My ADHD brain sometimes struggles with sustained attention, but it excels at seeing connections and patterns. I've noticed that teams with empathetic documentation cultures also tend to have better debugging practices, more inclusive code reviews, and frankly, happier developers.

A Simple Practice That Changed Everything

Now, before I commit any non-trivial code, I ask myself: "If I encountered this function at 11 PM during an emergency, what would I wish I knew?"

That question has prevented more late-night debugging sessions than any testing framework or linting rule. It's my anchor in sometimes chaotic sea of software development.

Writing Love Letters to Future Developers

So here's my challenge to you, fellow developers: start treating your comments like love letters. Not to code, but to human being who will inevitably need to understand, debug, or extend what you've built.

Your Documentation Love Letter Checklist

❤️ Show You Care

Acknowledge complexity honestly

Apologize for necessary hacks

Add encouraging words

Share lessons learned

🗺️ Provide Navigation

Link to related files/functions

Explain architectural decisions

Point to relevant documentation

Include debugging breadcrumbs

Remember, every comment you write is a message in a bottle, cast into future ocean of your codebase. Make it count. Make it kind. Make it useful.

/** * A final thought for fellow developers reading this: * * Your code will outlive your memory of writing it. * Your comments are love letters to future you. * Your documentation is an act of service to your team. * Your empathy makes software world a little more human. * * From one developer to another: you've got this. * * - Ken M., Oregon Coast AI * * P.S. - There's always coffee in kitchen, and ocean * has wisdom for whatever bug you're chasing. 🌊☕ */
KM

Ken Mendoza

Co-founder, Oregon Coast AI

INTP • ADHD • Coastal Coder

"Writing code is a conversation with future. Let's make sure it's a kind one."

Waldport, Oregon Where code meets coast Fueled by empathy & caffeine

More from Ken's Programming Musings

Why I Name My Variables Like Old Friends

On emotional connection to clean, meaningful code

PSYCHOLOGY OF CODE

Zen of Debugging

When frustration becomes flow state

MINDFUL CODING

ADHD Programmer's Paradox

When scattered thoughts become superpowers

NEURODIVERGENT CODING