Server components are shaking up the CSS-in-JS ecosystem. Styled-components and Emotion are not compatible with it yet. But even then, CSS-in-JS libraries with a runtime impose a significant performance tax. In this lightning talk we will present the problem in more depth, all the options that the Material UI team explored, and why it eventually settled on Pigment CSS. Olivier Tassinari | MUI Olivier is CEO, co-founder at @mui • co-creator of Material UI • studied @telecomparis • ex @doctolib https://github.com/oliviertassinari https://x.com/olivtassinari This talk was given at React Conf 2024, co-hosted by Meta (https://www.meta.com) and Callstack (https://www.callstack.com/). See more React Conf 2024 talks here: https://conf.react.dev/talks Thank you to React Conf 2024's sponsors: 💎 Diamond Sponsor Shopify: https://remix.run/ 🏆 Platinum Sponsor Amazon: https://developer.amazon.com/apps-and-games?cmp=US_2024_05_3P_React-Conf-2024&ch=prtnr&chlast=prtnr&pub=ref&publast=ref&type=org&typelast=org 🥇 Gold Sponsors Sentry: https://sentry.io/for/react/?utm_source=sponsored-conf&utm_medium=sponsored-event&utm_campaign=frontend-fy25q2-evergreen&utm_content=logo-reactconf2024-learnmore MUI: https://mui.com/?utm_source=conf.react.dev&utm_medium=referral&utm_campaign=sponsor2024&utm_content=sponsorslist Abbott: https://www.jobs.abbott/software 🥈 Silver Sponsors Redwood: https://redwoodjs.com Expo: https://expo.dev/ 🌈 Diversity Sponsor Vercel: https://vercel.com