List of videos

Component libraries are the building blocks of modern front-end apps. Developers can create a component once and reuse it in many places to create consistent user experience. But what happens if a change accidentally breaks any of those components? That could affect many pages! Changes to size, color, layout, and phrases may unintentionally go undetected. How can we easily catch these bugs? Visual component testing! In this talk, we will: 1. Learn how visual testing differs from traditional automated testing 2. Demo visual tests for a live React app with Storybook components 3. Evaluate pros and cons of different visual testing techniques We will use [Applitools Eyes](https://applitools.com/products-eyes/) as our visual testing tool. After this talk, you will be better equipped to test your apps. All example code will be provided in a GitHub repository for you to clone and extend as well! Other sessions at this event 🚀🪐 https://www.conf42.com/js2022 — 0:00 Intro 0:46 Talk

Promises are the standard approach to handling asynchronous operations in JavaScript and TypeScript. While they are flexible and fun to program in, important downsides make our codebase less maintainable. For instance, errors in a promise are typed as any, they use eager evaluation, and you can completely omit a catch operation for error handling. So there should be something else we can use, shouldn’t it? In this talk, we will be learning how to use functional programming and some alternative asynchronous computations like TaskEither, ReaderTaskEither, and Futures to show how we can handle side effects and create more robust applications. Other sessions at this event 🚀🪐 https://www.conf42.com/js2022 — 0:00 Intro 0:46 Talk

Did you know that more than 250 000 websites are published every day? The majority uses too heavy fonts, too large/unnecessary images or utilises redundant libraries. These and other factors generate the carbon footprint. Actually, one view of an average website emits 4.6 g CO2 which sums up to 553 kg CO2 annually. Unfortunately, current solutions optimise only already existing websites. ec0lint is a tool for frontend developers that mitigates the carbon footprint of websites. It shows tips advising how to create a more climate-friendly code. Thanks to code optimization ec0lint can help in reducing CO2 emissions per one view from 4.6 g to ~0.2 g saving 529 kg CO2 (-96%!) annually. In the keynote, we want to share our knowledge about digital ecology with the audience, tips and tricks on how to mitigate digital footprint and information about the tool we created. Our website (active from the official release day 07.06.22): ec0lint.com An article with tips written by me: https://www.linkedin.com/pulse/change-your-online-habits-mitigate-climate-crisis-katarzyna-wojdalska/ An article about digital ecology written by me: https://www.linkedin.com/pulse/have-you-ever-wondered-how-much-carbon-emissions-your-wojdalska/ Our GitHub: https://github.com/ec0lint/ec0lint Other sessions at this event 🚀🪐 https://www.conf42.com/js2022 — 0:00 Intro 0:46 Talk

https://slack.com is a messaging app for business that connects people to the information they need. In this talk we’ll see how to extend Slack functionality by developing a custom app. We’ll use Slack’s SDK for Node.js, Bolt.js (https://api.slack.com/tools/bolt) and Salesforce as backend. The app will let us create and manage work travel requests on Slack, avoiding context switching and maximizing productivity. Are you ready to fly?? Other sessions at this event 🚀🪐 https://www.conf42.com/js2022 — 0:00 Intro 0:46 Talk

This is the story of my experience about application from scratch till fully workable service using React and Node JS. You will find how to setup the project, how to handle the session, how to build the interface, where to start and what to take into account in the development process for your first startup. You will see the whole infrastructure of the project with diagrams. You will get some code of communication between server and client using GraphQL and Apollo. You will see the appliance of algorithm training words, creating collections on MongoDB. Security part of protecting routes. All tools in one for simple startups just in one speech. Other sessions at this event 🚀🪐 https://www.conf42.com/js2022 — 0:00 Intro 0:46 Talk

I discovered MeteorJS when I was a co-founder/CTO of an early-stage startup and we desperately needed to develop quickly and be very flexible (180 degrees pivot over the weekend) upon the needs of clients. MeteorJS is a full-stack JS framework that helps build quickly. I will explain how MeteorJS works and how to utilize it in the best way. Also, will talk about the tradeoffs of using MeteorJS (vs traditional stacks) and the strategy for future migration to different more popular stacks. Other sessions at this event 🚀🪐 https://www.conf42.com/js2022 — 0:00 Intro 0:46 Talk

Join me for a talk on developing scalable event-driven applications with NestJS. If you’ve never tried NestJS - I’ll talk briefly about its advantages and use cases it can solve for you. We’ll explore a hands-on example of scalability issues that can happen and the common approaches to solving them. Thanks and see you. Other sessions at this event 🚀🪐 https://www.conf42.com/js2022 — 0:00 Intro 0:46 Talk

Jamstack, SSR, SSG, static rendering, Next.js, Gatsby, ISR, prerendering, edge handlers... JavaScript developers sure like making up new words! But what do they mean, *actually*? In this talk, I'll demystify those fancy concepts and propose a better definition of ""server-side rendering"" a web app. You thought ""server-side rendering"" and ""static rendering"" were different things? That you cannot render authenticated, paid or personalized content at build-time? That per-request SSR costs an arm and a leg? Then this talk will blow your mind! Based on this corrected definition of SSR, I'll show you how you can solve the ""rich guest/poor customer"" issue that arises when you don't use static rendering to its full potential. The result: ultra-personalized static websites, that cost nothing to host and deliver the best possible user experience. Segment your renders and make your customers rich again! Other sessions at this event 🚀🪐 https://www.conf42.com/js2022 — 0:00 Intro 0:46 Talk

Imagine you are hosting a private event and you want to create a website to invite all your guests. Of course, you'd like to have an easy way to just share a URL with every guest and they should be able to access all the details of the event. Everyone else should not be allowed to see the page. Even nicer if the website is customized for every guest and if you could use the same website to collect information from the guests (who is coming and who is not). Ok, how do we build all of this? But, most importantly, how do we build it quickly? How do we keep it simple and possibly host it 100% for FREE? I had to do something like this recently so, in this talk, I am going to share my solution, which involves a React SPA (built with Next.js & Vercel) and AirTable as a backend! In the process, we are going to learn some tricks, like how to build a custom React Hook and how to protect our app from AirTable query injection (yes, it's a thing)! Other sessions at this event 🚀🪐 https://www.conf42.com/js2022 — 0:00 Intro 0:46 Talk