Vladimir Klepov as a Coder

Complaining about tech interviews is the favorite pastime of software engineers.

My name is Vladimir, and I'm an engineering manager of a team building a banking app.

It's been almost 2 years since I moved to a team lead role, then to a full-time engineering management position after the expansion of our team.

It's hard to believe, but, starting mid-october 2023 I conducted 60 technical interviews and hired 10 people into our team.

I've been working with svelte exclusively for a year now, but I still manage to shoot myself in the foot every now and then when using reactive state.

We've already learnt a lot about svelte's reactivity system — the primary way to work with state in svelte components.

I open-sourced banditypes — the smallest runtime validation library for TS / JS.

I love writing, and I also love data.

Say I'm building a TODO app with two tabs: done and pending tasks.

I've been working with TypeScript for a long long time.

I’ve been to plenty of bad interviews.

I’ve taken part in well over a hundred tech interviews now, on both sides.

Many modern front-end libraries and apps obsess over their bundle size.

Every front-end project involves some automation to build it, test it, lint it, run dev servers, measure bundle size, and what not. npm scripts are fine for one-liners, but as the workflows grow more complex — run these things in parallel, then do somethi…

When our React apps get slow, we usually turn to useMemo to avoid useless job on re-render.

I used to teach a class on React.

Conditional rendering is a cornerstone of any templating language.

I love useRef, but it lacks the lazy initializer functionality found in other hooks (useState / useReducer / useMemo). useRef({ x: 0, y: 0 }) creates an object { x: 0, y: 0 } on every render, but only uses it when mounting — it subsequent renders it's thr…

So you've decided to open-source your project.

useEffect should run after paint to prevent blocking the update.

Semantic versioning, is the way to version packages in JS ecosystem.

React context is a cool feature, and I use it a lot for injecting configuration and making container / child component APIs (think <RadioGroup /> + <RadioButton />).

Ah, ref.current.

React state is the bread and butter of a react app — it's what makes your app dynamic.

Like many of you, I've read Dan Abramov's excellent article, making setInterval declarative with React hooks.

Lately I've converted a lot of class components to functional.

IE11 is not dead yet, and our library is supposed to run there and make russian grandmas happy.

useContext hook has made React Context API so pleasant to work with that many people are even suggesting that we drop external state management solutions and rely on the built-in alternative instead.

Doing code reviews for our hook-based project, I often see fellow developers not aware of some awesome features (and nasty pitfalls) useState offers.

We all love keeping bundle size under control.

Suppose you're making a cool library that sums numbers in an array.

Today we'll talk about updating state inside useLayoutEffect in reaction to prop changes.

As a guy who's somewhat responsible for a large chunk of front-end development infrastructure at our company, I've spent the last couple of months woried about the performance of our pre-commit checks.

Building dynamic arrays in JS is often messy.

Normally, JS event are handled while bubbling up the DOM tree, and we've all had the pleasure to catch an event from a child node on its parent.

My current obsession with statically checking JS code got me to appreciate eslint even more.

The other day I was doing my normal thing trying to force import '*.css' to be the last import in a file, which ensures a predicatbale CSS order.

The second quarter is coming to an end.

React refs appear to be a very simple feature.

Edit: the technique initially proposed in this post was not concurrent-mode safe.

It's no secret that react's useCallback is just sugar on top of useMemo that saves the children from having to see an arrow chain.

Timeouts are one of the key building blocks to make your app stable.

The other day I was working on a React-based library of huge, reusable SVG images, and I ran into performance problems.

For some reason, many developers disdain design.

The second most important React optimization technique after shouldComponentUpdate and friends is remount management.

The reckless coding culture of JS favors producing garbage.

Do not extend components.

With all the enthusiasm around functional design in javascript community, we've come to reject the concepts whose names remind us of object-orientation.

Cheer up, today is a quick tip day.

My previous post, a classic rant, how-bad-software-is-these-days kind, attracted unexpected and probably even unreasonable attention.