One job: open and render Markdown faster than the eye can perceive, using the absolute minimum of computer resources.
Documents map straight into virtual address space (src/core/mmap.zig) — text demand-pages from the OS cache, no read() copy.
Wide vector compares find line breaks; a branch-light pass classifies headings, fences, quotes, lists, tables, and rules into a packed 8-byte Line index (src/core/simd.zig).
Off-screen elements are culled — only intersecting tokens are parsed and laid out, with zero heap allocations on the hot path (src/layout/viewport.zig, src/core/parser.zig).
Borderless window, CoreGraphics clipping, CoreText rasterization — no Electron, no WebKit, no toolkit (src/platform/). A headless screenshot engine renders to PNG for visual regression in CI.
The read binary contains only what reading needs (< 200 KiB). All test and debug tooling lives in a separate read-test binary behind compile-time gates — never runtime flags. Full mechanism: architecture.md.