Founder of Scirra, developing game creation tools for ~10 years. Construct 2 was one of the first HTML5 game engines on the market, and Construct 3 is one of the first commercial game creation tools to run in the browser.
Porting a large Windows app to the web
We ported Construct 2 - a game development IDE with around a quarter of a million lines of C++ code - to the browser. We launched Construct 3 in beta this year and it's now live at construct.net. We have some pretty unique experience of developing complex web apps and there were some interesting challenges and successes along the way. I might touch on some of the topics I've blogged about recently (time permitting!), such as HTML imports - and layout performance