Why every new web app at PayPal starts with TypeScript

January 7, 2019

What happened that made TypeScript viable for me and worth migrating paypal-scripts for. I've been using TypeScript for ~1 week now. Migrating from Flow....

2018 in Review

December 31, 2018

An overview of what I've accomplished in 2018 and a bit about my goals for 2019. Whether you've had a great 2018 or not, I think it's important to look back...

Light the World ✨

December 24, 2018

A special week calls for a special email. I'll be back with regular emails about JavaScript (and TypeScript) next week! As developers, we have unique and...

React Hooks: Array Destructuring Fundamentals

December 17, 2018

React's upcoming useState hook relies on array destructuring, let's dive in and see how that feature works. React Hooks are currently available in the alpha...

React Hooks: What's going to happen to my tests?

December 10, 2018

How can we prepare our tests for React's new hooks feature? One of the most common questions I hear about the upcoming React Hooks feature is regarding...

What's Going to Happen to React Context?

December 3, 2018

With the cool new stuff coming to React (Hooks/Suspense), what's going to happen to the context api? Earlier this year, the React team introduced the first...

React Hooks: What's going to happen to render props?

November 26, 2018

What am I going to do with all these render props components now that react hooks solve the code reuse problem better than render props ever did? About a...

How Gratitude can make you a better developer

November 20, 2018

What does gratitude have to do with software development? This week in the United States we celebrate Thanksgiving Day. In the US, the celebration was...

useEffect vs useLayoutEffect vs useMutationEffect

November 12, 2018

The simple rules for when to use each. Note: If the words "React Hooks" doesn't ring any bells for you, then stop for a moment and go here to read/watch...

What does "Testing Implementation Details" even mean?

November 5, 2018

Testing implementation details is a recipe for disaster. Why is that? And what does it even mean? NOTICE: If you missed the 40% off early bird sale on...

Last call for 40% off TestingJavaScript.com!

October 26, 2018

Hey there, The number one question I get asked about TestingJavaScript.com: I'm seeing an outdated version of the site! I don't see a "buy" button...

There's still time to purchase TestingJavaScript.com at 40% off!

October 25, 2018

Hello! I'm sorry if you've already purchased the course. We're still working on making it so I don't send these to people who have already purchased the...

What's holding you back? (and course updates 😇)

October 24, 2018

Hi friends 👋, I can't believe how positive the response from the corgi email was yesterday 😂 So I'll just stick another cute gif in here for good measure:...

Where will you be 6 months from now?

October 23, 2018

Hi there, In the world of web development, time moves really fast. It’s almost like dog years. It’s so easy to feel like you’re falling behind, or just...

How to avoid slow and brittle end-to-end tests

October 22, 2018

A common mistakes people make when writing E2E tests that lead to slow tests NOTE: TestingJavaScript.com is still in early bird stage, but it wont be 40% off...

React is an implementation detail (and course FAQ)

October 20, 2018

…yep, you read that right. Most of the course actually has nothing to do with React specifically. I’m so excited about the response to my new Testing...

Common Testing Mistakes

October 19, 2018

TODAY IS THE DAY AND I AM REALLY EXCITED CAN YOU TELL!? Tell your boss, tell your co-workers, tell your dog 🐶. Today’s the day you can snag...

UI Testing Myths

October 18, 2018

Some common myths around testing and what the reality is... Today is my birthday!!! I’m celebrating a few ways. First, I invited folks on Twitter to do two...

The Merits of Mocking

October 15, 2018

What are you doing when you mock something, and when is it worth the cost? The more your tests resemble the way your software is used, the more confidence...

The time I messed up

October 11, 2018

That time I went too far with Test Driven Development and forgot a very important step We all have stories where automated tests could’ve saved us from...

Why you've struggled with testing

October 8, 2018

Some common struggles people have with testing, and things you can do to improve. The argument is long ended: You should be testing your mission-critical...

Demystifying Testing

October 4, 2018

How to get from aimlessly testing or not testing at all to really understanding how and what to test. In the next few weeks, you’re going to get bonus emails...

Eliminate an entire category of bugs with a few simple tools

October 1, 2018

How you can use a few simple static code analysis tools to avoid common programming bugs. You’ve probably heard of ESLint, Prettier, and Flow/TypeScript....

Confidently Shipping Code

September 24, 2018

Why I care about testing Have you read the book "Start With Why"? If you haven't, I recommend it. At least watch the TED talk. The premise of the idea is...

React/JSX as a server-side templating language

September 17, 2018

Using React function components to render your website's skeleton index.html NOTE: I've been teasing about something big that I have coming. I'm totally not...

How I am so productive

September 10, 2018

People regularly ask me how I get so much done. Here's my secret... I get asked about this at least twice a week, so I thought I'd save myself some time by...

Getting Noticed and Widening Your Reach

September 4, 2018

Some things you can do to gain a wider audience and get your stuff noticed This last week I had three people complaining to me (in individual interactions)...

Make Impossible States Impossible

August 28, 2018

A simple trick to simplify your application and component state This is a phrase I first heard from David Khourshid in his talk at React Rally 2017...

How to make the most out of conferences

August 20, 2018

Some specific things you can do as a conference attendee I spent the last week at React Rally in Salt Lake City. It was an awesome experience. It's easily my...

Why and How I started public speaking

August 13, 2018

Some stories and some advice from an international speaker and trainer When I was still in school in the Information Systems program at BYU, I discovered and...

mdx-deck: slide decks powered by markdown and react

August 6, 2018

Why it's awesome, what it is, how it works, and how to use mdx-deck. Before we get started today, I want you to know that if you're going to React Rally or...

unpkg: An open source CDN for npm

July 30, 2018

Let's learn how unpkg the service and the open source project can improve performance for your company's apps. FYI: Before I get into the newsletter today I...

Polyfill as needed with polyfill-service

July 23, 2018

How to maximize the performance of loading polyfills for your application users. In last week's newsletter "What is a polyfill", I talked about a situation I...

What is a polyfill

July 16, 2018

A few weeks back I found a bug with IE where all the user saw was a blank white page. If you've been around for a while in the wonderful world of the client-...

Why I Never Use Shallow Rendering

July 9, 2018

Tests should help me be confident that my application is working and there are better ways to do that than shallow rendering. Before we get into today's...

When to break up a component into multiple components

July 2, 2018

At what point does it make sense to break a single component into multiple components? Advanced React Component Patterns Course in Portland next week! Hey...

What is JSX?

June 25, 2018

You may use it every day, but have you seen what happens after Babel transpiles it? I think a critical part of understanding how to use React effectively is...

Test Isolation with React

June 18, 2018

Why your tests should be completely isolated from one another and how to do that. Read to the end, I've got some cool things in the "things not to miss"...

JavaScript default parameters

June 11, 2018

Today I thought I'd take you through one of the examples from my es6 workshop. Consider the following code: function getCandy(kind, size, upperKind,...

Dealing with FOMO

June 4, 2018

What is "Fear Of Missing Out" and how to deal with this natural unhealthy tendency. 🚨 Announcements 🚨 Advanced React Online and Live! Join me in my online...

💯 UPDATED: Advanced React Component Patterns ⚛️

June 1, 2018

Now featuring the latest React APIs (like context) and entirely new patterns (like state reducer props). TL;DR My highly popular course has been updated...

When to use Control Props or State Reducers

May 28, 2018

You've probably used components or elements that implement the control props pattern. For example: <input value={this.state.inputValue}...

Write your own code transform for fun and profit

May 21, 2018

With babel-plugin-macros 🚨 DON'T MISS THE OPPORTUNITY TO WATCH 2 OF MY FRONTEND MASTERS COURSES ABSOLUTELY FREE FOR THE NEXT 3 DAYS 🚨 Learn more. ✨ Also, I'm...

✨ Free Frontend Masters Courses ⚛️ for a Week 🎉

May 18, 2018

Hey friends! I thought you all might be interested in knowing that Frontend Masters has made two of my recent courses absolutely free for a limited time (one...

React DevTools

May 14, 2018

This last week I had someone criticize using React component state because: there are no browser dev tools for inspecting [component state] Maybe this person...

Prop Drilling

May 8, 2018

[POLL]: Do you know what I'm talking about when I refer to "the prop drilling problem" in #ReactJS? Yep Maybe Nope 🐓 This twitter poll I started is still...

How I learn an Open Source Codebase

April 30, 2018

Does this look different? Whelp, I've graduated from the free tier of TinyLetter.com (limited to 5,000 subscribers) and moved to ButtonDown.email! A big...