Lume

A fast, native macOS workspace for your Markdown, notes, code, and config files.

Point Lume at any folder and get a responsive, Finder-like sidebar plus a native editor — built entirely in Swift 6 + SwiftUI + AppKit as a real .app. No Electron, no web wrapper, no JavaScript editor. It opens files in milliseconds and takes your clicks the instant the window appears.

Platform: macOS 14 (Sonoma) or later · Apple Silicon & Intel Status: early rebuild — the responsive core is in place (see Roadmap).

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What works today

• 📂 Open any folder as a workspace — choose a directory (⌘O) and browse it in a native sidebar. Directories expand lazily, so opening a large tree never stalls.
• ✍️ Native TextKit 2 editor — open, edit, and save text files. Markdown gets lightweight live highlighting (headings, bold, emphasis, code, links). A selected file opens focused and ready to type.
• 💾 Save & find — ⌘S saves (atomically, off the main thread); the editor provides native Find (⌘F) and Undo (⌘Z).
• 🧭 Stays out of your way — non-text files offer "Open in Default App"; your last folder and window position are restored on relaunch.
• ⚡ Snappy by construction — file reads happen off the main thread and the editor is fully native, so the UI never blocks on disk or rendering.

Architecture

Module	Responsibility
LumeKit	UI-free, unit-tested domain logic: folder scanning, file classification, document load/save, markdown tokenizing.
Lume	Thin SwiftUI/AppKit shell: window, sidebar, TextKit 2 editor, view-model.

The project is generated from project.yml via XcodeGen into a standard Xcode app target — which is what gives Lume normal macOS window activation and event handling out of the box.

Build & run

brew install xcodegen          # one-time
xcodegen generate              # project.yml -> Lume.xcodeproj
xcodebuild -project Lume.xcodeproj -scheme Lume -configuration Debug -derivedDataPath build build
open build/Build/Products/Debug/Lume.app

Run the tests:

xcodebuild test -project Lume.xcodeproj -scheme Lume -destination 'platform=macOS' -derivedDataPath build

Roadmap

Lume is being rebuilt from a clean native foundation. Planned increments, each returning a feature set the earlier prototype had:

• Tags + GROUPS (tags as virtual folders), pinning, display names, colorful tags
• Dedicated viewers: PDF, image, source code, .env, YAML/TOML/JSON config, HTML
• File management (create / rename / move / delete) with Undo, drag-to-tag / drag-to-pin
• SSH remote editing (shipped) — connect to a host from the sidebar source switcher, browse, and atomically edit remote text/config files
• GitHub repo editing (shipped) — see below

GitHub repos

Open any GitHub repository from the source switcher (owner/repo, a pasted URL, or the Browse Your Repos picker — requires the gh CLI signed in via gh auth login). Browse the repo tree, pick a branch, and edit text/config files with Lume's editors; ⌘S commits directly to the active branch ("Update "). If the file changed on GitHub since you opened it, the save is rejected and Lume offers to reload — your edits are never silently lost, and neither are anyone else's.

One Favorites list for every source

Pin local files, SSH paths, and GitHub repo files into a single Favorites list. Remote favorites carry a small source badge (⚡ host for SSH, branch icon

• repo for GitHub); clicking one connects to its source if needed and opens the file — or reroots the tree, for a pinned folder. Right-click any remote tree row to Add/Remove from Favorites. Favorites persist locally (no server sync).

Favorites follow you across Macs

Your remote favorites (SSH + GitHub) and manually-added SSH connections sync across the Macs signed into your iCloud account — pin a remote file on one, find it on the other; remove it anywhere, it's gone everywhere. Local-file favorites and your private keys stay on each machine. Requires iCloud Drive and a signed build with the iCloud capability; without iCloud, favorites work normally and just don't sync.

• App Sandbox + signed distribution

License

MIT — see LICENSE.