A/B Testing

Basic guide to running a good A/B test

This is a basic introduction on how to run a good A/B test. A/B testing is a method where your user pool is segmented into multiple groups, allowing you to test different product interactions and understand how these changes affect user behavior. For any metric / data driven team, A/B testing serves as a critical tool in measuring success. This is part of a series (The Opinionated Engineer) where I share my strong opinions on engineering practices. ...

June 6, 2025

No Blame SEV (Incident) Culture

Less finger-pointing, more preventions

Every time there’s a major outage at Meta, the first question I get from friends and family is usually “did they fire the person who caused it?” which is where I have to explain this concept of No Blame SEV Culture. Especially for an outage so big that a significant number of users are affected, the individual causing it likely does not have ill intent and there are likely multiple different processes and systems that failed along the way to get us here in the first place. ...

May 30, 2025

Code Review Culture

Review today or debug tomorrow

Ask a programmer to review 10 lines of code, he’ll find 10 issues. Ask him to do 500 lines and he’ll say it looks good. - @girayozil Code review is a really subjective thing where each team or even individual runs things very differently. However, a bad code review process can lead to bad code smells and unnecessary tech debt (just ask all the vibe coders out there 🫣). I will try my best to share my rather opinionated takes while explaining the reasoning behind each of them. ...

May 23, 2025

Building a Simple Newsletter Service

Just a DB with some HTMLs

When I had the idea on the series about The Opinionated Engineer, I figured maybe that’s something worth setting up a newsletter service over. That said, after some consideration, I just thought that I didn’t need anything too complex and decided to roll my own because “how hard could it be?”. As far as I can tell, I think it’s working fine so far(?) and took me around one whole day to put the whole thing together from my couch. You can find all of it’s source code here on GitHub. ...

May 21, 2025

The Art of Posting

It's both self-promotion and communication

This piece is specifically more about Meta’s unique culture of “posting” about things but I imagine it can be a useful reference on communication in general. Many people loathe this process and complain about how it’s just a lot of “self-promotion” and while there’s definitely some truth to it, it’s also a valuable communication avenue that you can leverage to your advantage. As we will explore further below, posting by itself is more of a bonus as the post will still require actual substance (which is your work lol). ...

May 16, 2025

Push Fearlessly with Automated Testing

Move faster by moving slower

Conventional wisdom is that writing tests slows you down, because the alternative is that you don’t need to write tests. In fact, Meta (then Facebook) was famously lacking of automated test inline with it’s famous “move fast and break things” mantra. However, from what I’ve seen, I beg to differ. This is part of a series (The Opinionated Engineer) where I share my strong opinions on engineering practices. Subscribe to the newsletter today! You will need to manually get this secret from here Subscribe You can also checkout previous issues here before deciding. When to write tests? # If you love something, put a ring test on it. ...

May 4, 2025

The Opinionated Engineer

Strong opinions about engineering practice

Historically, my personal blog has been mostly about “how to do x”, “guide on making y” but never about ideology or engineering practices. This new series intends to change that where I’ll explore the more opinionated side of myself especially around engineering practices instead of just the pure technical stuff. Topics # I have not fully planned out the entire series but here are a few topics I have in mind (or have released) so far… ...

May 4, 2025

Self-Hosted GitHub Actions Runners

Turning your old laptops into GARs

This post will focus more on the “why” and some of the quirks around doing so instead of the “how” since GitHub already have a very comprehensive guide around it. Just wanted to take a bit of time to acknowledge that it’s been almost 3 years since I last wrote a blog post. It’s been a busy 3 years for sure but hopefully I’ll be writing more consistently moving forward. (I do have quite a few half-written drafts that I’ve never published which I can’t tell if it’s still relavant at this point.) ...

April 25, 2025

Automated Link Preview Image Card

Taking screenshots with Playwright

A while ago, I saw this tweet thread from Simon Willison about how he added social media preview cards to his TILs. He detailed how he did this through a combination of Puppeteer, Vercel, SQLite, and some other stuff I didn’t understand 😅. At that time, I was manually taking these screenshots by hand to be included as part of the commit, which is to say it’s not very efficient. Anyway, this stayed on my backlog of “things to explore” for a really long time until recently during this long weekend (where I also took additional PTOs), I had some free time and decided to look into this. The goal is simple, automate creating the preview images for a list of given / defined urls. ...

May 31, 2022

Rebuilding Personal Site from Scratch

Only HTML + CSS with no frameworks

As time goes on in my journey of experimenting with different technologies on building a web interface, I figured it’s time for my personal site to return to the fundamentals. So I decided to build it with only HTML + CSS with one of the goals being that it should work perfectly fine with JavaScript disabled. Before this, it’s built with Vue. You can still find the source here. Design # Inspiration # Skip this next paragraph if you’re not interested in my old site’s origin story. ...

January 31, 2022