Overall I spent about 2 years on the development. The more interesting part is tracking the cursor movements when user starts recording and transforming it into smooth cursor movements and click-driven zoom effects. I use Swift scripts for low-level cursor tracking, then run a post-processing pipeline: resampling to timeline FPS, outlier-jump clamping, stillness detection/snap-to-median, cursor-type flicker smoothing, and coordinate normalization for area vs full-screen recording. Clicks are converted into timed zoom segments with easing so playback feels intentional, not jumpy
For the video preview and export I use PixiJS. Before I used Remotion, which had the needed functionality, but the rendering was slower because it relied on a Chromium + FFmpeg pipeline. PixiJS uses WebGL so the 4k video rending is much faster. It took me about 3 weeks on switching from Remotion to PixiJS. The rendering speed improved by about 3-4x on the same projects and hardware. I was honestly relieved when it finally worked
I would never have built this product without AI assistants, since I had never built an Electron app before. Many things were not obvious to me, and my first users ran into lots of issues and edge cases I didn’t even know existed. I spent the last year fixing them.
I'm happy to answer on your questions