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Facebook is extremely over-engineered for a birthday reminder app

Interviewer: Invert this binary tree Junior dev: Here's the algorithm I memorized Experienced dev: Let me find a library for that Senior dev: Does inverting the tree align with our core business objectives?

I have no idea what to name my baby At this point I'll just name him "utils"

Why hire a $150k/year dev when you can just pay $200/month for an AI coding agent and $200k/year for a dev to fix its code?

⚛️ React tip: when conditionally rendering component based on some string enum (like a role), use an object to map enum values to components. This can be cleaner than using conditional operators, and it keeps the logic organized & clear.

If you're using Tailwind, don't sleep on child selectors. They clean up your styles and eliminate repetition. Vibe coding agents aren't smart enough to do this. (if you're using CSS, keep scrolling)

When a developer finally learns about state machines

Developers: "I guess accessibility is important to some people, we'll get around to it" Developers at conferences: 🗣️ "CAN YOU INCREASE THE FONT SIZE I CAN'T READ THE CODE"

Fun fact: "auth" is short for "it's either authentication or authorization but I don't remember the difference right now"

It's Monday, survey the damage, cry a little, and start cleaning up

⚛️ React tip: for most forms, you don't need useState()... or any hooks at all! You can read form data directly from the form by element name: Object.fromEntries(new FormData(formEl)); You don't even need a form library most of the time.

Vibe coding is incredible. I built a working MVP of a complex browser extension in just 2 days. Here's how: Day 1: Prompted the coding agent and watched it struggle through two different extension frameworks Day 2: Read the docs and coded it myself, with light LLM assistance

⚛️ Here's a fun React tip: `useReducer` is a better `useState`, and it's easier to adopt than you may think. Group related values together and spread them in the reducer. Then, updating is just: updateThing({ prop: newValue }) And there's even more benefits to `useReducer`...

I wonder how much code out there is unnecessarily slow because it looks like this: const a = await taskA() const b = await taskB() instead of: const [a, b] = await Promise.all([taskA, taskB]) Async/await is a really convenient footgun

🔢 Quick tip: if you're sorting an array in JS and keep forgetting how to write the compare functions (like I do), here's a mnemonic device: (a, z) => a - z // ascending, like "a to z" (a, z) => z - a // descending, like "z to a" Hope this helps someone!

I have no idea what to name my baby At this point I'll just name him "utils"

For code examples, which one is more readable? 🅰️ Destructured or 🅱️ Dot notation?

If you're using Tailwind, don't sleep on child selectors. They clean up your styles and eliminate repetition. Vibe coding agents aren't smart enough to do this. (if you're using CSS, keep scrolling)

90% of software complexity comes from developers having opinions

Why do so many React developers dislike useReducer()?

Interviewer: Invert this binary tree Junior dev: Here's the algorithm I memorized Experienced dev: Let me find a library for that Senior dev: Does inverting the tree align with our core business objectives?

I wonder how much code out there is unnecessarily slow because it looks like this: const a = await taskA() const b = await taskB() instead of: const [a, b] = await Promise.all([taskA, taskB]) Async/await is a really convenient footgun

There is a "pattern" I've seen in a lot of React codebases where a setState() triggers a useEffect() which may call another setState() which triggers another useEffect() etc. What do you call this pattern, besides "Rube Goldberg machine"?

We donut know how to espresso how excited we are to be deploying this baby to prod next year 😊 Any boy name suggestions? Naming is hard

useEffect doesn't cause bugs Developers who misuse useEffect cause bugs

Fun fact: there's not a single piece of tech advice that you can give on here that everyone will agree with. Prove me wrong

Things I wish were table-stakes in every web app: - Typing auto-focuses main input - Enter submits forms - Esc closes modals - Validation on blur, not while I'm typing - Let me decide whether a link opens in a new tab or not What else?

Why hire a $150k/year dev when you can just pay $200/month for an AI coding agent and $200k/year for a dev to fix its code?

⚛️ React tip: when conditionally rendering component based on some string enum (like a role), use an object to map enum values to components. This can be cleaner than using conditional operators, and it keeps the logic organized & clear.

Tip: instead of checking the array length to see if it's non-empty, you can check the first item when all the items are expected to be truthy. ❌ if (arr.length > 0) ✅ if (arr[0]) It's shorter, cleaner, and plays nicer with TypeScript's `noUncheckedIndexedAccess` setting.