neofsn

Status: beta. neofsn is under active development. Expect rough edges, changing behavior, and the occasional bug.

Requires macOS 15 (Sequoia) or later.

A spatial filesystem navigator for macOS — a modern homage to SGI's FSN (the "File System Navigator" famously shown as the 3D UNIX interface in Jurassic Park). Folders become blue platforms, files become flat slabs you fly through, and a warm pulsing halo marks whatever you've selected. Built with SwiftUI for the shell and SceneKit for the 3D scene.

"It's a UNIX system. I know this."

Features

• 3D folder visualization. Each folder is a plate; its files are flat slabs and its subfolders are raised macOS-blue platforms carrying their own contents.
• Fly camera. WASD / arrow keys to move, Q/E to change altitude, drag to look, scroll to dolly. Hold Shift to move faster.
• Configurable coloring — toggle between age heat-map (FSN-style: red this week → through orange, yellow, green, teal, blue → purple for >1 year) and file-type palette (categorical: code, images, audio, video, docs, archives, config, …). Switch live from the top bar; the scene recolors in place without a rescan.
• File-type icons stamped on each slab using a shared FileKind taxonomy that drives both the icon and the type-mode color.
• Layered descent. Stepping into a subfolder drops a new plate beside-and-below the current one and pans the camera to it — the parent stays on screen, so you keep your bearings instead of losing context to a full redraw.
• Hierarchical sidebar mirroring the tree, with two-way sync: pick something in 3D and the sidebar scrolls to it; click in the sidebar and the camera flies to it.
• Interactive breadcrumb bar — jump to any ancestor folder with a click.
• Selection halo. The selected item gets a soft warm-gold ring of light around its base, gently pulsing — the app's signature visual.
• Remembers your last folder. The opened folder is persisted as a security-scoped bookmark and reopened automatically on the next launch.
• Expanded metadata HUD with kind chip, name, full path, size (or file/subdir count for folders), modified/created dates, permissions (rwx), and age — plus an inline action strip: Quick Look, Open, Copy Path (⇧⌘C), Reveal in Finder, and Descend (for folders).
• Finder integration & Quick Look — open in the default app (⇧⌘O), reveal in Finder (⌘R), copy path (⇧⌘C), or press Space to Quick Look the selection.
• Reset view (⌘0, the scope button, or click empty space) re-frames the current folder.

Requirements

• macOS 15.0 (Sequoia) or later — this is the app's minimum deployment target
• Xcode 26 or later to build. The .xcodeproj is committed, so you can open it directly. XcodeGen is only needed if you change project.yml.

Building

Open neofsn.xcodeproj in Xcode and build, or from the command line:

xcodebuild -project neofsn.xcodeproj -scheme neofsn -configuration Debug build

project.yml is the source of truth for the project structure. The generated neofsn.xcodeproj is committed so a fresh checkout opens without extra setup. If you edit project.yml, run xcodegen generate (brew install xcodegen first) and commit the regenerated project alongside it.

Testing

Unit tests for the model layer live in neofsnTests/ (Swift Testing). Run them with:

xcodebuild -project neofsn.xcodeproj -scheme neofsn -destination 'platform=macOS' test

Running

The easiest way is to open neofsn.xcodeproj in Xcode and press Run (⌘R).

To launch a command-line build directly, open the product Xcode just built:

open "$(xcodebuild -project neofsn.xcodeproj -scheme neofsn -configuration Debug \
  -showBuildSettings 2>/dev/null | awk '/ BUILT_PRODUCTS_DIR /{d=$3} END{print d}')/neofsn.app"

On first launch the 3D view is empty. Click Open… (or press ⌘O) and choose a folder to visualize. The app is sandboxed and uses security-scoped bookmarks, so it only ever reads the folders you explicitly pick — and it remembers the last one, reopening it automatically on the next launch. Once a folder is open, fly around with the keyboard and mouse (see below), click items to inspect them, and step into subfolders to descend.

Keyboard & mouse

Action	Binding
Move / strafe	W A S D or arrow keys
Altitude	E (up) / Q (down)
Speed boost	hold Shift
Look around	left- or right-drag
Dolly	scroll
Select / enter	single-click
Open file / re-root folder	double-click
Quick Look	Space
Open in default app	⇧⌘O
Reveal in Finder	⌘R
Copy path	⇧⌘C
Open folder…	⌘O
Back	⌘[
Reset view	⌘0

Project layout

neofsn/
├── neofsnApp.swift              # App entry point, window configuration
├── Model/
│   ├── BrowserViewModel.swift   # Navigation state, scanning, selection, focus requests
│   ├── FileKind.swift           # File-type taxonomy (icon symbols + type-mode palette)
│   ├── FileSystemNode.swift     # Tree node model
│   ├── FileSystemScanner.swift  # Async (cancellable) directory scanner
│   └── LastFolderBookmark.swift # Security-scoped bookmark for the last opened folder
├── Scene/
│   ├── SceneBuilder.swift       # Builds level plates, slabs, icons, labels
│   ├── SceneHostView.swift      # SCNView host, level stack, picking, framing, Quick Look
│   └── FlyCameraController.swift# WASD/look/scroll fly camera
└── UI/
    ├── ContentView.swift        # NavigationSplitView shell, top bar, breadcrumbs, empty state
    ├── SidebarView.swift        # Hierarchical tree sidebar
    ├── MetadataHUD.swift        # Selected-item metadata panel
    └── Theme.swift              # Color, type, and panel design tokens

neofsnTests/                     # Swift Testing unit tests for the model & scene math

scripts/
├── generate-icon.swift          # Renders the app icon set
└── gen-compile-commands.sh      # Generates compile_commands.json for sourcekit-lsp

Tooling notes

The project structure is defined in project.yml and generated via XcodeGen; the resulting .xcodeproj is committed. For editors that use sourcekit-lsp, run scripts/gen-compile-commands.sh to generate a compile_commands.json so cross-file symbols resolve. The build itself always goes through xcodebuild / Xcode.

Acknowledgements

Inspired by Silicon Graphics' fsn (1992) and its cameo in Jurassic Park. This is an independent reimplementation and is not affiliated with SGI.

License

BSD 2-Clause. See LICENSE.