When documenting APIs, developers often link to ISO 8601 as the standard for computer-readable date and date-time format. Dates and times (and time zones!) are complicated. There are so many edge cases and pitfalls. I’m sure every developer has a battle story about them. It’s good to delegate that hard…

When I was working on my small side-project library, I needed to represent a missing value. In the past, I’d used the nullable approach in simple settings and Option (aka Maybe) when I wanted more control. In this case, neither felt correct so I came up with a different approach…

I firmly believe all creative people hate when others tell them what to do. When instead of problems to solve, they are handled solutions to implement or, even worse, isolated tasks to just complete. Yet, the world is full of micromanagers. Over my career, I’ve heard countless complaints about how…

Since the very first moment I learned about TypeScript, I knew there’s gonna be this one thing I’ll always hate: Enums. So un-elegant, so old-school, and so why-do-you-pollute-my-runtime. Well, I was wrong. I use Enums now. At least some of them. Let me show you. What is an Enum in TypeScript? First, let’s quickly talk about…

Recently I was re-reading one of my favorite engineering articles The Trident Model of Career Development by Patrick Kua. The sentence that caught my eye this time was a note about the role of a Tech Lead: They should have good but not necessarily the best [tech] skills in the…

This is a simple tutorial for embedding a YouTube channel into an AMP. With a small modification, this can be used for any website. I recently started a YouTube channel about JavaScript. To promote it I wanted to embed the latest video on my home page. …

This article is a reply to stefan judis's article How the rest operator and default values affect the function length property. Stefan shows how a function length is computed when it includes a rest parameter or parameters with a default value. A quick summary: const fn1 = (a…

Simplify API and middleware tests with lesser-known features — This is a transcript of a presentation given at October Node.js Berlin Meetup. What is Koa and what is Jest Let's briefly describe the libraries we will be working with. Koa (koajs.com) is a JavaScript web server framework. It was developed by the people behind a more famous Express as a lightweight and expressive ‘spiritual successor.’

Recently I got into a discussion about how to decide a function is pure in JavaScript. The whole concept of pureness seems to be blurry in such a dynamic language. …