Improving site performance by shipping more CSS

GitHub’s move from CSS-in-JS to CSS Modules shows that front-end performance can be materially improved by reducing runtime styling overhead and migrating through a design system with feature flags and gradual rollout. For CIOs and technology leaders, the key takeaway is strategic: platform and UI architecture decisions can have direct impact on page speed, server efficiency, and developer velocity, and large-scale modernization is safest when treated as an incremental, test-driven transformation rather than a big-bang rewrite.