When it comes to career, Charlie has one trick: to focus. But that doesn’t mean that you shouldn’t try different things — currently a senior front-end developer at 
Netlify
, she is also a sought-after speaker, mentor, and a machine learning trailblazer of the JavaScript universe. "Experiment with things, but build expertise in a specific area," she advises.
What led you to software engineering?
My background is in digital marketing, so I started my career as a project manager in advertising agencies. After a couple of years of doing that, I realized that I wasn't learning and growing as much as I wanted to. I was interested in learning more about building websites, so I quit my job and signed up for an intensive coding boot camp called General Assembly. I absolutely loved it and started my career in tech from there.

What is the most impactful thing you ever did to boost your career?
I think it might be
public speaking
. Going on stage to share knowledge about things I learned while building my side projects gave me the opportunity to meet a lot of people in the industry, learn a ton from watching other people's talks and, for lack of better words, build a personal brand.

What would be your three tips for engineers to level up their career?
Practice your communication skills. I can't stress enough how important it is to be able to explain things in a way anyone can understand, but also communicate in a way that's inclusive and creates an environment where team members feel safe and welcome to contribute ideas, ask questions, and give feedback. 
In addition, build some expertise in a specific area. I'm a huge fan of learning and experimenting with lots of technologies but as you grow in your career, there comes a time where you need to pick an area to focus on to build more profound knowledge. This could be in a specific language like JavaScript or Python or in a practice like accessibility or web performance. It doesn't mean you shouldn't keep in touch with anything else that's going on in the industry, but it means that you focus on an area you want to have more expertise in. If you could be the "go-to" person for something, what would you want it to be? 

And lastly, be intentional about how you spend your time and effort. Saying yes to everything isn't always helpful if it doesn't serve your goals. No matter the job, there are always projects and tasks that will help you reach your goals and some that won't. If you can, try to focus on the tasks that will grow the skills you want to grow or help you get the next job you'd like to have.

What are you working on right now?
Recently I've taken a pretty big break from side projects, but the next one I'd like to work on is a prototype of a tool that would allow hands-free coding using gaze detection. 

Do you have some rituals that keep you focused and goal-oriented?
Usually, when I come up with a side project idea I'm really excited about, that excitement is enough to keep me motivated. That's why I tend to avoid spending time on things I'm not genuinely interested in. Otherwise, breaking down projects into smaller chunks allows me to fit them better in my schedule. I make sure to take enough breaks, so I maintain a certain level of energy and motivation to finish what I have in mind.

You wrote a book called
Practical Machine Learning in JavaScript.
 
What got you so excited about the connection between JavaScript and ML?
The release of TensorFlow.js opened up the world of ML to frontend devs, and this is what really got me excited. I had machine learning on my list of things I wanted to learn for a few years, but I didn't start looking into it before because I knew I'd have to learn another language as well, like Python, for example. As soon as I realized it was now available in JS, that removed a big barrier and made it a lot more approachable. Considering that you can use JavaScript to build lots of different applications, including augmented reality, virtual reality, and IoT, and combine them with machine learning as well as some fun web APIs felt super exciting to me.

Where do you see the fields going together in the future, near or far? 
I'd love to see more AI-powered web applications in the future, especially as machine learning models get smaller and more performant. However, it seems like the adoption of ML in JS is still rather low. Considering the amount of content we post online, there could be great opportunities to build tools that assist you in writing blog posts or that can automatically edit podcasts and videos. There are lots of tasks we do that feel cumbersome that could be made a bit easier with the help of machine learning.

You are a frequent conference speaker. You have your own blog and even a newsletter. What made you start with content creation?
I realized that I love learning new things because I love teaching. I think that if I kept what I know to myself, it would be pretty boring. If I'm excited about something, I want to share the knowledge I gained, and I'd like other people to feel the same excitement I feel. That's definitely what motivated me to start creating content.

How has content affected your career?
I don't track any metrics on my blog or likes and follows on Twitter, so I don't know what created different opportunities. Creating content to share something you built improves the chances of people stumbling upon it and learning more about you and what you like to do, but this is not something that's guaranteed. I think over time, I accumulated enough projects, blog posts, and conference talks that some conferences now invite me, so I don't always apply anymore. I sometimes get invited on podcasts and asked if I want to create video content and things like that. 
Having a backlog of content helps people better understand who you are and quickly decide if you're the right person for an opportunity.
What pieces of your work are you most proud of?
It is probably that I've managed to develop a mindset where I set myself hard challenges on my side project, and I'm not scared to fail and push the boundaries of what I think is possible. I don't prefer a particular project, it's more around the creative thinking I've developed over the years that I believe has become a big strength of mine.
***
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Developer, writer, creator, says the headline of Lee’s site, a front-end developer with 
10k YouTube subscribers
 and 5k newsletter followers. Today an internationally recognized speaker and author of extensive courses on React and Next.js, he says he owes his success to sharing what he was learning online. "The best time to start with content creation was yesterday!" he exclaims. 
What led you to software engineering?
I've always enjoyed creative work, especially building things from scratch. I have roots in design and photography, which ultimately led to a perfect match for front-end development. And how did I go from a designer to a developer? I wrote an extensive post about my journey on my blog. 
What is the most impactful thing you ever did to boost your career?
Hands down, writing online. Sharing what I was learning online led to new connections and opportunities I couldn't have imagined. It's helped me generate passive income, land new jobs, and make some great friends. The best time to start was yesterday! And if you need a tip or two on how to kickstart your content creation, I wrote a short article that will help you make heads and tails of the whole process.
What would be your three tips for engineers to level up their career?
First, leave the code in a better place than you found it. 
Second, work on improving your written and verbal communication. 
And third, write documentation. You'll be the developer everyone loves. 
What are you working on right now?
I'm entirely focused on leading developer relations at Vercel and Next.js but have been entertaining making another programming course as a side project. I'm also considering rebuilding my personal site — for the 10th time!
Do you have some rituals that keep you focused and goal-oriented?
I try to stay active, get plenty of sleep, and focus on long-term goals. It's easy to get caught up in the day-to-day, so I frequently try to think about what I want to achieve in the long run. If I'm not making progress towards a better future, then it's time to change something. As for staying focused, it's incredibly important I'm working on something I truly believe in. Otherwise, I would likely get bored very quickly. I'm bullish on Next.js, Vercel, and our mission of building a better web.
Apart from your job, you also maintain a very successful content platform. Why did you start, and how did you grow it to 80k blog post views, 10k YouTube subscribers, and 5k newsletter followers?
My golden rule is being helpful online. At the end of the day, if I'm consistently helping people in a positive way, all the metrics will go up and to the right over time. I started writing online about seven years ago and haven't looked back since.

You also launched two learning projects: 
React 2025
 and 
Mastering Next.js
. Can you tell us more about them and why you decided to provide them for free?
I didn't set out to create programming courses but ultimately ended up creating the resources I wished I had earlier in my career. Most of my content creation was solving problems that "past Lee" faced. For Next.js specifically, when I started creating content, it was still relatively new and hadn't reached critical adoption. I believe that helped with the growth of my courses and audience. After some time, I ended up making both free for everyone. Money wasn't the main incentive for me, but rather helping other people — and past Lee.
Are you working on a new personal project at the moment?
Not now. But I'm leading a team of content creators at Vercel, so there's a lot in the works here now! My team is made up of some wonderful people, and this has been an exciting transition in my career.
What open-source projects would you recommend keeping an eye on or contributing to?
I've been very interested in Rust lately, with Next.js investing more into using Rust (through SWC) to optimize compiling and bundling. Check out SWC and expect more educational material on Rust in the future from our team.

What pieces of your work are you most proud of?
I'm most proud of the students who have taken my courses and ultimately landed jobs or created their own products. It's very fulfilling for me and the reason I love being a content creator.
***
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Speakers are not made — they are born out of circumstances. And Tomasz is a perfect example of a self-starter who rose to the occasion. “I started at local meetups and climbed my way up to bigger and bigger events,” he says, nodding at the fact that he's now also a seasoned instructor revolutionizing modern commerce. How did he get there?
What led you to software engineering?
It's been quite a journey. Ever since I was a kid, I was interested in technology, but I was definitely not one of those five-year-old prodigies that installed Arch Linux on their fridge. I wrote my first program on a Commodore 64 copying an entire page of arcane characters from a book to a computer and hitting Enter. And then I watched the screen flash in different colors.
I built — okay, copied and pasted random code till it worked, which I kind of do till this day — my first website when I was around 12, but I never thought that web development would turn out to be my career. In fact, I explicitly did not decide to pursue a Computer Science degree for various reasons. I felt I wasn't good enough and thought that programming was not for me.
Instead, I decided to pursue a master's degree in Electronics and Telecommunications, which, to my surprise, was most likely harder than the CS curriculum. Along the way, I got an opportunity to learn C++, which wasn't exactly a cakewalk, but it led me to my first internship, which led to another one where I was a part of an eight-week-long paid bootcamp. There I learned web development from scratch, an opportunity I'm forever grateful for. And I've been programming for a living ever since.
What is the most impactful thing you ever did to boost your career? 
It was back in 2017 when I decided to give public speaking a shot. Like all tech speakers, I started at local meetups and slowly but surely climbed my way up to bigger and bigger events.
Contrary to a popular notion, speaking at tech conferences is not exactly something you do for money. The connections, networking, and genuine friendships that happened because of all those events are priceless, though. The doors you get to open, the places you get to see, the people you get to meet — if you're able to, I cannot recommend speaking at tech events enough.
Tomasz's workstation
 
What would be your three tips for engineers to level up their career?
 
I wrote everything I wished I knew earlier in this blog post. In short: talk to humans rather than machines, have a deep understanding of what you are building and why, and don't be afraid to say, "I don't know." Also, learn in public, as some of my colleagues mentioned in their interviews.
What are you working on right now? 
I'm currently a front-end engineer at
Stedi
, where we're building a fully serverless platform for companies to integrate and exchange business transactions with each other. Stedi is a fully remote startup with employees from all around the globe, and I'm a part of a ridiculously talented team of engineers who happen to be from the same city I'm from!
The business domain we're in hasn't seen much innovation in decades, and it's such an exciting space to contribute to. We're working on challenging and complex problems. After all, revolutionizing modern commerce can't be easy. 
Do you have some rituals that keep you focused and goal-oriented? 
I'm not sure if this is a ritual, but I strive to challenge myself as often as I can and pursue new personal and professional growth areas. My favorite answer to the famous "Where do you see yourself in five years?" question is, "I don't know." I feel like if you do know where you'll end up in five years, you may not be thinking broadly enough about your potential and possibilities. In this line of work, it's crucial to be focused on growth and becoming a lifelong learner.
You're an egghead.io instructor, where you've contributed with two courses and more than 170 lessons. What do you find rewarding about the experience?
Joining egghead was life-changing for me. Apart from the financial incentive, having the ability to record a lesson or a course in my bedroom and teach something useful to hundreds, if not thousands of developers, is remarkable. I'm forever grateful to Joel and the entire egghead crew for having me. If you're interested, you can read a bit more about my journey with them in the post.
What would you say are essential qualities and skills for teaching — and learning?
Keep your eyes open as there's always more to learn. Try to learn something new every week, if not every day. 
When teaching, optimize for boredom. It's better to explain something again to an expert rather than to a beginner who may feel excluded.
Also, when one teaches, two learn, so use teaching as a tool of solidifying your own knowledge.
And don't forget to be kind. Whenever you teach someone a concept that may seem totally obvious to you because you mastered it years ago, make sure to remember that you were a beginner not so long ago too.
What open-source projects would you recommend keeping an eye on or contributing to?
I'm a huge fan of everything Tanner Linsley is working on, especially React Query. In my humble opinion, it's the best library since jQuery, so make sure to check it out. It's just excellent.
What pieces of your work are you most proud of? 
Whenever someone reaches out to me saying that a video, article, podcast, or talk I created helped them, it always means the world to me. It's an incredible feeling to have something you wrote a couple of months ago reach out to someone else from across the globe and help them grow as a developer.
***
Follow Tomasz on Twitter

As it is with many developers, his path to coding was not straightforward. And looking at Shawn's bio, it's apparent he applied that experience to his whole career: he's the head of developer experience at Temporal.io, author of a bestselling book on progressing career in IT, and a sought-after mentor and speaker. His number one advice? “Marketing is not beneath you.”
What led you to software engineering?
My first career was in finance, and I did a lot of trading of currency derivatives and stock portfolios. We had to do a lot of number crunching in Excel, Python, and then Haskell. I was the guy putting together all that data. I didn't call myself an engineer, but I was writing software. I saw that there are many good ideas in software engineering that I should learn and that once I do that, my life will be significantly better. So I left finance and went through a boot camp to learn all the software engineering practices. My first job was at two Sigma as a front-end engineer. Then I joined Netlify as a developer engineer and then AWS. 
What is the most impactful thing you ever did to boost your career?
This will sound very similar to Ken's thing, and it's called learning in public. I did it when I was at Sigma because I wasn't learning much at work. I was in New York City, there were many meetups, and I decided to give myself my own mentors speaking there, writing blog posts, sharing them, and just finding more ways to grow apart from inside of my company. And I realized that it was way more effective than just waiting for the right boss or co-worker to teach me.
Also, the dev community has been so welcoming and supportive. You learn, share what you've learned, and people will correct you if you're wrong. And once you're wrong, you will never forget what you have been learning. So if you have a pretty thick skin and a low ego, you can learn a lot. In fact, with my most recent job, I wrote a blog post about what I thought was missing in the serverless ecosystem based on what I had seen at AWS and Netlify. Someone commented on my blog, a VC read the comments and hired that guy to head the products at Temporal. And then that guy turned around and hired me based on that blog post. 
For me, learning in public has opened up jobs and speaking opportunities on multiple continents. And I've made a lot of friends who are genuinely interested in technology.
What would be your three tips for engineers to level up their career? 
Understand that some marketing is unavoidable and that knowing how to market yourself authentically is not scammy. It's not beneath you. It's what you need to do to get people to know you, your skills, and the quality of your work. A lot of developers have a build-it-and-they-will-come mentality, and it does not serve them very well. Invest some time into developing your marketing and understanding how to market yourself. 
I have a blog called How to market yourself without being a celebrity. When people look at marketing, they see the celebrity path, the influencer path. But many people don't want to be an influencer, so they'll say: "No marketing for me!" Let's disconnect those two things. Also, there's a difference between marketing yourself internally within your company — which you should always do — and marketing yourself externally with other developers.
My second tip is to clone open-source apps. Clone something that already exists so that you stop making all these little product decisions. Maybe your implementation will be better, which is great; that's how the industry improves. And if it's worse, you start to understand the underlying trade-offs of your project. 
And a third one?
Many people have the cold start problem when it comes to networking and content creation. Yes, you will not get much response when you start. So the way to guarantee response is what I call a "pick up what they put down" approach. If you want feedback, start giving feedback, mainly whenever people put out something new.
When somebody you respect publishes a new demo, a new library, a new blog post, or a new workshop, summarize it, respond to it, react to it. Not with a YouTube reaction video, but actually respond to the meat of the content. Ask questions: Do you agree? Do you disagree? What else can you do with this implementation? Pick up on the things. Find bugs in the demos and the libraries, and you're guaranteed to get a response from that.
I think that's an excellent starting point because these people are already influential. Almost definition, they have more ideas, and they know what they do. You work with them, become a collaborator. Eventually, you start to disagree with them, and you feel forced off into your own path. That's, I think, a great way to get started.
You are now working on developer experience at 
Temporal.io
. What does it entail?
Temporal is an open-source microservices orchestration system, which you could compare to Apache Airflow or AWS Step Functions. But we're better. There's a core server that is open source, and then there's all this stuff around it that needs to reach developers: documentation, developer relations, web UI, and SDKs. And I'm the head of developer experience helping each team in those areas. They are not essential to the server itself but important to how developers experience the product. 
I have overarching excitement in my career about helping technologies cross the chasm. I'm not sure who came up with the term, but the idea is that when you switch over from early adopters to a broad audience, there is a big gap in the middle where you have to fill in a lot of gaps with developer experience. That's what I focus on. 
Do you have some rituals or tools that keep you focused and goal-oriented?
I try to do time blocking. For example, interview calls are on Fridays, which gives me focus on work from Mondays to Thursdays. Within the day, you have different time blocks as well. And if you can block off time for yourself too, I think you can get a lot more done.
Apart from your daily job, you are a writer and speaker, and you recently published The Coding Career Handbook. What inspired you to write it?
Mostly the feedback from my essay on learning in public. It was the most impactful piece of writing I've ever done; it reached over a million people. I can write about technical stuff, and I think it would be easier to sell, but React will be over someday. The thing that will not be over is career stuff, the evergreen things. 
When I decided to write the book, I had some time between my Netlify job and my Amazon job. So I wrote a poll, and the one with the more enthusiastic response was the career stuff. For whatever reason, this is the most valuable topic to my readers. Also, I think there's a gap in the market for leveling juniors and seniors. You can find many materials on how to learn to code and crack the coding interview. And then there's a big gap. But many people are coming into tech as juniors, and there's a lot of companies wanting to hire seniors — and nobody focuses on developing juniors into seniors.
So I'm trying to contribute my thoughts as well as the thoughts of others. I collected 1,500 references to other people's ideas on becoming a senior engineer in the book. And I think if I keep at this — this is version one — I will build it up into the ultimate resource on how to become a senior engineer.
And if you were to highlight one idea from your book, which one would it be?
I'd say the most underappreciated part of my book is the strategy section — the importance of picking the right thing to work on rather than just being a clean coder or choosing the right tech stack. Understanding how money is made from your software is key to selecting the right company and positioning yourself correctly within the company. 
You are also very active in the community: you've contributed to several other books, have a 
34k+ following on Twitter
, helped to run the React subreddit... How has it impacted your career?
It helps you to know everybody. It allows you to understand what's going on. I'm typically the source of news to my team, and they appreciate that. Also, if you're friends with everybody, you don't have to know everything — it's all coming from that community. 
What open-source projects would you recommend keeping an eye on or contributing to?
I left the React community because I was getting more and more interested in Svelte. I do think it is an underrated framework for front-end developers. It's not for everybody, but I think it solves a good set of problems, including state management, styling, and animation. At React, we still don't have good answers for these things after all these years.
What pieces of your work are you most proud of?
Mostly the community behind the coding career handbook. I set up a semi-private Discord channel for people who opt into the community, and seeing people get jobs, double their pay when they go from junior to senior — that's really exciting. It's a great place for discussion where you can be totally honest. Realizing that that's something that I can do for ten years and not get bored of it, that's something I'm proud of.

Often overlooked, sometimes under-appreciated, testing is a crucial but difficult part of software delivery. Watch these great talks to ensure your JavaScript code is always spotless and runs smoothly.
Bugs are an essential part of the global ecosystem, but finding them pollinating flowers is much better than finding them crawling through your apps. Errors and glitches can make or break your product, which is why testing is such an important step before shipping. However, JavaScript testing is not a straightforward process, from picking the right approach and tools to identifying the bugs themselves. 
Thankfully, every problem has a solution, and every JS testing approach has a champion willing to share their knowledge. So tune in to the videos below and make your next app as flawless as possible.
Iris Schaffer: Fantastic bugs and where to find them
Every bug is different: some lurk around for months, others appear suddenly after the upgrade of a dependency. Some are introduced us while others other teams or systems. Some are painfully obvious and affect all users, and others only occur in some instances. And the ways of finding and, eventually, preventing them are just as diverse: be it a snapshot, unit, integration, end-to-end or automated visual tests, every kind comes with its challenges and opportunities. 
Testing UIs is hard, but in the end, only test automation can give us the confidence we need to move fast and refactor our code relentlessly. In this talk, Iris Schaffer looks at what kinds of bugs there are, which tests are most effective for catching them, and how we can implement various methods using modern front-end technologies.
Christian Bromann: The evolution of browser automation
In this session, Christian Bromann looks at what's happened behind the scenes in browser automation throughout the years and what the future has in stock for us. You will see how web testing will develop and what challenges this will bring for conventional frameworks like Selenium or WebdriverIO and new frameworks such as Cypress, Puppeteer, and Playwright. Lastly, you will experiment with some new automation capabilities these frameworks provide to test some of the latest web features.
Jessica Sachs: Component testing with Vite, Vue, and Cypress
In this talk Jessica Sachs, you will explore what a developer workflow with Vite, Vue, and Cypress looks like and how fun testing can be. Jessica is a core team member of vue-test-utils, develops at Cypress, and is considered a testing guru the community.
Applitools 🤝 Cypress: State of the union
This is the opening keynote for Front-End Test Fest delivered Angie Jones, Head of Developer Relations at Applitools, and Amir Rustamzadeh, Director of Developer Experience at Cypress. In the video, they look at the upcoming capabilities of Cypress to tame flaky tests and test components along with their guests and discuss the innovative features of Cypress and Applitools. 
You'll learn how they can be used to not only meet but exceed your quality objectives and how component testing, flake detection, and visual testing can significantly enhance your functional, cross-platform, accessibility, and localization quality initiatives.
Tomasz Łakomy: Shipping high-quality JS apps with confidence
Shipping bug-less code to production is — obviously — impossible. But still, users deserve the best experience we can give them, stipulates Tomasz Łakomy in this talk. And he argues that if you gain confidence in the way you build your software, you can sleep better knowing that it won't explode in the middle of the night. 
In this talk, Tomasz covers something he calls The Testing Spectrum, which is a set of tools, practices, and mindset of shipping high-quality code to production.
Bushra Alam: The allure of adding tests to Azure DevOps
Continuous testing is the process of executing automated tests as part of the software delivery pipeline. Teams that use Continuous Testing can catch bugs early and often, resulting in code that is always production-ready. Join Bushra Alam to learn how to integrate your end-to-end tests with Azure DevOps.
Patrick Kunka: Simulating network conditions with JavaScript
When working with video streaming, accurately simulating customer network conditions for development and testing is crucial. In this talk, Patrick Kunka sheds light on using containers and server-side JavaScript to programmatically shape network conditions. 
You'll also learn how to gain valuable insights about the behavior and performance of client-side JavaScript from Adaptive Bitrate video players to entire single-page applications.

It doesn't matter if you're only learning ReactJS fundamentals or you're ready to boost your skills with advanced courses, the remote conferences brought a number of great presentations for everyone
over the past 12+ months
. We've selected the top ones available online.
React, the favorite library of web and mobile developers alike, doesn't need a long introduction. The framework has become essential for creating modern applications, and while other JS tools have expanded or revised it, React is still the one to beat. 
That's why we've compiled the following list of great conference talks from 2020/2021 – the season of COVID but also the season of awesome remote events – that will guide you through all things React, from state management to improving performance. We highly recommend that you watch these if you want to improve your next JavaScript project!
Shawn Swyx Wang: Lessons to outlive React
There was a time before React, and there will be time after it. If you tie yourself too closely to any technology, you might trap yourself and miss the next wave. So let's zoom out from the state management library 'du jour' — what timeless lessons can we learn from React? 
In the talk, Shawn Swyx Wang discusses the lessons he's learned from studying React, especially the ones that are going to stick with him for the rest of his career.
Sara Vieira: React is hard but not why you may think
React is hard. There are many resources for getting started, but things can get complex and confusing when writing full-blown applications. Navigating the React ecosystem is a lot to take in and sometimes highly overwhelming. With this talk, Sara hopes to help you understand some of its 'gotchas' more clearly while giving you some confidence when building bigger React apps.
Brandon Bayer: The dawning of a new age for fullstack React
New frameworks like Blitz.js and Redwood.js are ushering us into a new era for full-stack development. They are mixing old concepts and ideas with cutting edge technologies to make full-stack developers more productive than ever. Brandon Bayer's talk will take you on a journey through time and show you the exciting things that lie ahead.
Kent C. Dodds: Managing React application state management
Application state management is one of the hardest parts of building and maintaining React applications. One thing that makes it complicated is when you aren't thoughtful about how that state is organized and categorized in your app. There are different kinds of state, and they require different approaches for management. And when you try to treat all app state the same, that's when problems come into play. 
Kent C. Dodds' talk deals with what some of those categories are and how you can drastically simplify your application code and improve your app's performance thinking about and organizing your state differently.
David Khourshid: XState – The visual future of state management
With this talk David Khourshid, you'll learn how state modeling with state machines and statecharts can improve the way you develop your React applications. You'll also get a sneak peek of never-before-seen visual tools that will take state management to the next level.
Paul Henschel: Making games in React
Paul Henschel's talk focuses on react-three-fiber — and with his guidance, you'll be making a mini-game. You'll see how you can make it through all the heavy boilerplate and math without losing your mind, even when you're a beginner. You'll also see how to translate the process to anything, be it a game or a website with some exciting visuals and effects.
Omri Bruchim (Wix): Making your React Native app fast
In the past five years, the Wix mobile app has gone through quite a bit: a brand new look was launched, a large number of features were added in a short time, and the number of users tripled. Unfortunately, one implication of product growth is slower performance, especially when it comes to seamless transitions, fluent animations, and the general slickness of the app. 
Wix made a tremendous effort to improve these regressions, and the ongoing efforts have so far resulted in almost 60% cumulative improvement in all performance metrics. In his talk, Omri Bruchim from Wix dives deep into all of the secret ingredients for better performance in React Native applications and gives practical examples on improving startup time, responsive gestures, and preload prioritization. 
Nader Dabit: Next.js on AWS
In this video, you'll learn how to implement authentication in a Next.js app using AWS Amplify and Amazon Cognito. Nader Dabit's talk covers everything from SSR authentication, SSR redirects, protected routes, client-side redirects, and authenticating a request in an API route.

JavaScript rules the world, and staying up-to-date with the latest JS developments is a must. So sit down and relax while watching amazing talks from 2020 and 2021 online conferences.
What's your library of choice: React, Angular, Vue? Whichever that may be, JavaScript powers the web. That's why we made the following list of the best JS talks to help you stay in the loop. It doesn't matter if you're a beginner or a pro looking for advanced JavaScript courses — we've got you covered. 
The list features hands-on tutorials on data visualization or neurotechnology but also talks regarding the philosophy and
the future 
of the language. So dive in and enjoy!
Shawn Swyx Wang: The third age of JavaScript
The way we write JavaScript in 2030 will be completely different than in 2020, predicts Shawn Swyx Wang. And he says why: the slow death of IE11 and rollout of ES Modules will converge toward a new generation of JavaScript tooling. These tools are faster, typesafer, and polyglot, leading to better developer and user experience, and you can get familiar with them in this talk.
Charlie Gerard: Building brain-controlled interfaces in JavaScript
Neurotechnology uses technological tools to understand more about the brain and enable a direct connection with the nervous system. Research in this space is not new; however, its accessibility to JavaScript developers is. 
Over the past few years, brain sensors have become available to the public, with tooling that makes it possible for web developers to experiment with building brain-controlled interfaces. As this technology is evolving and unlocking new opportunities, Charlie Gerard looks into one of the latest devices available, how it works, the possibilities it opens up, and explains how to start building your first mind-controlled app using JavaScript.
Stuart Langridge: You really don't need all that JavaScript, I promise
JavaScript is the way to add interactivity to your sites, provide a slick and delightful user experience, and make everything fast, easy, and clean. But at some point, everything changed: the tail started to wag the dog instead, and development became Javascript-first. 
In this video, Stuart Langridge talks about how you maybe shouldn't rely on JS as much as you're told to and gives some practical strategies for building sites without reaching for a JS framework as the first, last, and only tool for making the web happen.
Lin Clark: Making JavaScript on WebAssembly fast
JavaScript runs many times faster in the browser than it did two decades ago. And that happened because the browser vendors spent that time working on intensive performance optimizations in their JavaScript engines. Because of this, JS is now running in many places besides the browser. But there are still some environments where the JS engines can't apply those optimizations in the right way to make things fast. 
As Lin Clark explains, her team at Fastly and she are working to solve this, beginning a whole new wave of JavaScript optimization work. In this talk, she'll show you how to improve JavaScript performance for entirely different environments using WebAssembly.
Alexander Esselink: Future of Svelte
"I've been looking for a good reactive application platform for a long time. At some point, a friend of mine introduced me to Svelte, and I immediately fell in love with it," says Alexander Esselink, aka Dexter, a full-stack developer at Passionate People. In this talk, he'll give you a comprehensive introduction to the future of Svelte, which is one of his favorite tools for building web applications.
Gil Fink: Using data visualization to fight Covid-19
The year 2020 will be remembered as the year of the Covid-19 pandemic. During the lockdowns, Gil Fink was involved in building a web app for the government health department. The app visualized the chain of infection and helped decision-makers understand the characteristics of the virus spreading and other aspects. In this talk, Gil speaks about how he used D3 and React to build the app.
Chloe Noh: DIY data visualization in JavaScript
As long as you have an idea about what you want to show, you can use JavaScript to collect and visualize data, says Chloe Noh. In this video, she'll show you her process of data visualization, from selecting the main subjects and key indices for storytelling to choosing the right type of visualization charts. 
Jason Mayes: TensorFlow.JS 101 – ML in the browser and beyond
Discover how to embrace machine learning in JavaScript using TensorFlow.js in the browser and beyond in this speedy talk Jason Mayes. Get inspired through a whole bunch of creative prototypes that push the boundaries of what is possible in the modern web browser and take your first steps with machine learning in minutes. 
By the end of the talk, you will understand how to recognize an object of your choice, which could then be used in any creative way. Familiarity with JavaScript is assumed, but no background in machine learning is required.