Repos and specs we actually build on, not a bookmarks dump. shadcn/ui - not a component library, a component vendor; copy the source, own the code, restyle to your register. DESIGN.md - Google Labs' open spec for machine-readable design systems; the first file format an agent respects that a human can also just read. React Email - design tokens that survive email clients; the missing third render target after web and social. Remotion - video as a React render; the moment motion became code-reviewable. The theme across all four: portable, inspectable, yours. Anything that locks your system inside its editor did not make the list.