Developer tool website

A dedicated Markdown workspace for developers who live in specs.

Viewer-first. Fast. Technical. Focused.

KatanA helps engineers read, navigate, and share technical documentation without dragging in the complexity of a general-purpose knowledge app.

macOS native

English + Japanese

Homebrew and direct download

fit

Built for technical documentation workflows

KatanA is not positioned as a general knowledge system or IDE. It is a focused reader and workspace for documentation-heavy development.

Viewer-first

The first public goal is a stable viewer that makes specs and architecture docs easier to inspect and trust.

AI-assisted

KatanA is aligned with workflows where Markdown is the contract between humans and AI agents.

Native

Rust and egui keep the app lightweight and responsive even when documentation grows.

background

The app comes from the gap between lightweight Markdown tools and documentation-heavy engineering work.

Spec-driven development needs Markdown to be readable before it is editable.
AI-agent workflows make specifications and ADRs more central, not less.
General note apps and heavy editors add too much ceremony around simple review work.

intent

The website is designed for problem-led discovery instead of brand-only traffic.