Tiny Go binary that turns any folder of markdown into a navigable wiki. Point it at a repo, get a sidebar of every .md file and rendered HTML at localhost:8090. Zero config.

go install github.com/avolent/cortex@latest

Or build from source:

git clone https://github.com/avolent/cortex
cd cortex
go build

cortex                              # serve current directory on 127.0.0.1:8090
cortex -dir ~/path/to/repo          # serve another folder
cortex -dir ~/repo -addr 127.0.0.1:9000  # custom port
cortex -dir ~/repo -addr :8090      # bind all interfaces (LAN-accessible)
cortex -dir ~/repo -index index,home  # fall back to index.md/home.md when a folder has no README

cortex -dir ~/notes -export ./out   # render to static HTML, exit

Open http://localhost:8090. Or upload the -export output to any static host (GitHub Pages, Netlify, S3). The default bind is loopback only; pass -addr :8090 to expose on the LAN.

• Walks the directory recursively, collecting every .md file. Skips .git, node_modules, vendor, tmp, dist, build, .next, .cache, .claude, and any dotfile/dotdir.
• / serves the root README.md.
• /path/to/foo serves path/to/foo.md.
• /path/to/foo.md also works, so relative [link](other.md) references in your markdown resolve naturally.
• /path/to/dir falls back to path/to/dir/README.md if present, else the first -index name that matches (see -index flag).
• Embedded images (.png .jpg .jpeg .gif .svg .webp .ico) are served as static assets.
• Sidebar shows folders as collapsible <details> blocks. README is pinned to the top of each folder; everything else is alphabetical.
• Light + dark theme via prefers-color-scheme.
• Live reload: edits to any .md or image trigger an automatic browser reload via Server-Sent Events. New folders are picked up automatically.
• Static export (-export <dir>): same renderer writes the whole wiki to disk as HTML for hosting on GitHub Pages, Netlify, S3, etc.

• Search (use Ctrl-F).
• Syntax highlighting in code blocks.
• Frontmatter, custom themes, config files.

If you need any of that, use Hugo or MkDocs.

• github.com/gomarkdown/markdown for rendering.
• github.com/fsnotify/fsnotify for live reload.