Sid Patil


Dive into Kotlin/JS with Sebastian Aigner

calendar_today favorite_border 568 views hourglass_empty 3 min read workspaces Community

New Kotlin IR compiler, Kotlin/JS performance, Flutter vs Kotlin/JS for web and much more! Sebastian Aigner from Jetbrains answers the communities questions


Event Details

We’re going fully online into 2021 as a community our last meetup was a global collaboration of communities with Android Worldwide. To kickstart things in the Kotlin Universe Kotlin Mumbai organized a meetup with Sebastian Aigner from Jetbrains to discuss their future plans with Kotlin/JS.

  • Speaker: Sebastian Aigner, DevRel team at Jetbrains
  • Date: 6th March 2021
  • Location: Online

Here’s a few words from Sebastian before you watch the session: Let’s talk about how we can use Kotlin to leverage one of the most exciting platforms of the last decade: the browser. We’ll see what it takes to get started with writing Kotlin/JS applications, and get a feeling for the ecosystem, including libraries specific to Kotlin/JS, but also multiplatform. We’ll also talk about news and plans the team at Jetbrains has to make the JavaScript target for Kotlin even better in the future. Let’s explore together!


Questions from the community

Answers are directly time stamped in the Youtube video

  • Can I start Web Dev directly with Kotlin JS or go with JS+React then return to Kotlin being an Android Developer
  • Are there any plans to support JetBrains Compose UI development toolkit with Kotlin JS for web development?
  • Is it possible to generate source maps for Kotlin JS Code to possibly make it easier to develop?
  • Can we make a cross-platform App with Kotlin which runs on the web and also on ios and Android?
  • How does Kotlin/JS compare to another multi-platform framework like flutter web?
  • Does Kotlin/JS in a multiplatform app(full stack) support raw CSS files or we have to use Kotlin CSS DSL itself?
  • Are there any limitations when targeting JS on the usage of Kotlin’s language features either as a part of the std library or coroutines? For eg like using flows.
  • Any plans for Vue.js with Kotlin JS?
  • Does this custom DSL for HTML use PSI files under the hood to generate the HTML files? or is it done differently?
  • Is RClass specific to React components only?
  • How does it work under the hood? Does it translate code to JS just like TypeScript does?
  • How does Jetbrains ensure that with every release of Kotlin the functionality and compiler support for each platform remains consistent?
  • Is Kotlin/JS stable and confident enough to make a simple frontend website?
  • Are the website made with Kotlin/Js responsive?
  • How will be the performance on different browsers like chrome, safari, etc?
  • Any recommended documentation or quick snippets of code where I can easily learn about the basic components? (no libraries)
  • How can I add an npm module whose only method returns a Promise. I haven’t been able to compile it. And all I find on docs is capitalize or camel case example.
  • Can I host the website made in Kotlin/Js on Firebase, Netlify, etc?
  • Are there any example GitHub projects showcasing a website or any webpage using kotlin JS and a backend?
  • Kotlin over javascript sounds like a good payoff but kotlin over typescript doesn’t sound all that good right?
  • Does Kotlin/js support different levels of style encapsulation like style that applies only to a particular component / some CSS specifically to the whole app?
  • How to use styled-components? can you give any reference for that?
  • Which is better in terms of performance react js or kotlin/js?
  • How easy it is to make use of hardware-acceleration, maybe a GPU I have while using TensorFlow.JS?

Wrapping it up

One of the most interesting meetups we have hosted, our community asked a lot of interesting questions, you can listen to Sebastian answer them in the video directly. Our organizing member Rishit Dagli did a fine job at adding timestamps in the YouTube video to make things easier for you.

About the author

Siddhesh Patil is an Android Engineer at DeliveryHero. Building core ordering experiences at Foodpanda and Foodora. He is the organzier of Kotlin Mumbai, a developer community in Mumbai, India. Find talks, articles and latest developments in Android and Kotlin on this website

Sid Patil is an Android Engineer and Kotlin Advocate based in Berlin, Germany. He works at Delivery Hero, building ordering experiences for food delivery and Q-commerce brands like Foodpanda and Foodora.

Share on


More articles to read