-
SurveyJS
Open-Source JSON Form Builder to Create Dynamic Forms Right in Your App. With SurveyJS form UI libraries, you can build and style forms in a fully-integrated drag & drop form builder, render them in your JS app, and store form submission data in any backend, inc. PHP, ASP.NET Core, and Node.js.
I've added optional cache compression using SnappyJS, which is tiny and much faster that gzip/deflate. But even then decompression adds hundreds of ms to every page view, so it is disabled by default. I have also offloaded rendering of background image to Web Worker using OffscreenCanvas.
If I understand it correctly, they are using the Sqoosh Wasm build. And the latest commit to the jxl decoder is this which is using v0.3.1 from feb 2021. Maybe the decoder would be faster if it was compiled from a recent build.