Zhassulan Serikuly: Engineering notes https://zhassulan.netlify.app/blog Short write-ups of engineering work: the problem, what changed and the numbers. en Fri, 16 Oct 2026 00:00:00 +0000 500K map objects, first render cut from 800 to 480 ms https://zhassulan.netlify.app/blog/half-a-million-map-objects https://zhassulan.netlify.app/blog/half-a-million-map-objects Fri, 16 Oct 2026 00:00:00 +0000 A Mapbox GL JS interface with 300K–500K geospatial objects: first render from about 800 ms to about 480 ms. Moving from the Pages Router to the App Router https://zhassulan.netlify.app/blog/pages-router-to-app-router https://zhassulan.netlify.app/blog/pages-router-to-app-router Thu, 15 Oct 2026 00:00:00 +0000 Modernizing legacy React/Next.js codebases at Ciklum: App Router, strict TypeScript, and INP from about 280 ms to about 150 ms.