Evolving a Live Game Engine: Introducing ECS Without a Full Rewrite | Alex Zhorau | GameDev Day 2026

This talk explores how the Entity Component System (ECS) paradigm can be introduced into an already shipped mass-market game without rewriting the entire engine or disrupting a live product. Drawing on experience with proprietary engines and Unreal Engine, it covers the practical challenges of connecting ECS to legacy scene representation, components, and scripting layers, as well as the compromises required around memory layout and performance. The session presents a staged migration approach and explains why a hybrid ECS and legacy architecture is often the most sustainable outcome for a live game. Speaker: Alex Zhorau, Software Engineer, Meta Medium: https://medium.com/@AZhorau Recorded at JetBrains GameDev Day Online 2026, a free online event for the game development community. Watch all GameDev Day 2026 talks: https://www.youtube.com/playlist?list=PLRyISO8WW3lQ Explore JetBrains tools for game development: https://www.jetbrains.com/gamedev/ #JBGameDevDay #GameDev #ECS #GameEngines