A native macOS app for viewing and editing Markdown files. SwiftUI document-based app; rendering in a WKWebView with GitHub-style typography and automatic dark mode.
Rendering stack (bundled locally, works offline):
- markdown-it — CommonMark + tables, strikethrough, autolinks, plus footnote and task-list plugins
- highlight.js — syntax highlighting in fenced code blocks (GitHub light/dark themes)
- Mermaid —
```mermaidfences render as diagrams, theme-matched to system appearance
The preview page loads once per window; keystrokes re-render via a JS call, so scroll position is preserved and there's no flicker. See SAMPLE.md for a feature demo.
Sublime-style folder browsing: File → Open Folder… (⇧⌘O) shows the folder tree in a left sidebar. Markdown files appear as clickable links (accent color, pointing-hand cursor, underline on hover); other files are listed dimmed for context. Click a Markdown file to open it in the right pane. Opening a single file (⌘O or Finder double-click) opens its parent folder in the sidebar automatically. Folders can also be dropped on the Dock icon.
- Preview (⌘1) — rendered, read-friendly view. Default on open. Links open in your browser; pinch to zoom.
- Split (⌘2) — editor and live preview side by side; preview keeps its scroll position while you type.
- Edit (⌘3) — plain-text editor with monospaced font, undo, and smart-quote substitution disabled (so Markdown syntax stays intact).
⌘S saves; unsaved changes are flagged in the status bar and window title, and switching files or quitting with unsaved edits prompts save/discard/cancel. Word/character count in the status bar.
12 document themes via the paintpalette toolbar button or View → Theme: Default, GitHub, Serif, Sepia, Solarized Light/Dark, Dracula, Nord, Tokyo Night, One Dark, One Light, and Terminal. Default/GitHub/Serif follow the system light/dark appearance; the rest are fixed. Code highlighting and Mermaid diagrams re-theme to match. View → Custom Stylesheet applies your own CSS on top of any theme.
Zoom with ⌘= / ⌘- / ⌘0 (scales both preview and editor; current level shown in the status bar).
- Find in document (⌘F) — searches the preview in Preview/Split mode and the raw text in Edit mode; Enter/chevrons cycle matches with wrap-around, Esc closes.
- Outline — the list toolbar button shows the heading hierarchy; click to jump (smooth-scrolls the preview, or moves the cursor in Edit mode).
From the File menu: Print… (⌘P), Export as PDF… (⇧⌘E), Export as HTML… (self-contained, diagrams included), and Export as Word… (.docx via textutil; basic fidelity). Exports render offscreen with your current theme, so they work from any mode.
The workspace folder is watched via FSEvents. If the open file changes on disk (a script regenerates it, a git checkout, another editor saves), the view reloads automatically when you have no unsaved edits; if you do have unsaved edits, a banner offers Reload From Disk or Keep My Version instead of clobbering your work. New and deleted files show up in the sidebar automatically without collapsing your expanded folders.
swift build -c release
./build-app.sh # assembles dist/Markable.appDrag dist/Markable.app into /Applications. To make it the default for .md files: right-click any .md file → Get Info → Open with: Markable → Change All.
Full local setup guide: INSTALL.md · Sharing the app with others: DISTRIBUTION.md