Sextant

A native macOS app for the ZSA Voyager.
Edit your layout on your Mac, build and flash the firmware locally, and watch the keyboard live.

Install · Guide · Releases · Safety · Privacy

Note

Sextant is an independent project, not affiliated with or endorsed by ZSA Technology Labs. ZSA, Voyager, Navigator, Oryx and Keymapp are trademarks of their owners, used here only to describe compatibility.

Features

Edit

• Every key, with undo: tap, hold, double tap and tap-then-hold actions, chords, labels, per-key colors and tapping terms.
• Search every keycode from the key, or find any command, key or setting with ⌘K.
• Layers, macros, combos, firmware settings and the Navigator, with each layer showing what it inherits.
• Import from Oryx by pasting a layout link. It's read-only: no login, and nothing changes in your Oryx account.
• History and export: revisions you can compare and restore; export JSON, QMK source, firmware, PNG or PDF.

Build and flash

• On your Mac, with a pinned, sandboxed QMK toolchain that's downloaded once.
• A careful flasher that writes only the application region and checks every image first (see Safety).
• One keyboard, two Macs: optionally store the layout in the firmware, so Sextant on your other Mac reads it back.

Live

• The board follows the keyboard: the active layer and the keys you press.
• An overlay of the layer you hold, over any app, placed where you like.
• Layer switching from the menu bar or global shortcuts, and App Layers that follow the app you're in.
• Lighting and heatmap: paint a layer's LEDs and preview them on the keyboard, and see which keys you actually use.

The layer overlay, over any app	The menu bar

The guide walks through each feature.

Install

brew install --cask afrase/tap/sextant

Or download the zip from Releases. Sextant tells you when a newer version is out.

• Requirements: macOS 26 on Apple silicon. Editing works without a keyboard.
• Tested on a Voyager with the STM32 bootloader. Images for the GD32 bootloader are refused, and the Navigator trackball is untested.
• Signing: releases are signed ad hoc, not notarized. The Homebrew cask clears the quarantine flag for you; a zip you download yourself needs System Settings › Privacy & Security › Open Anyway on first launch.

Safety

• The flasher writes only the application region, [0x08002000, 0x08042000), and can't mass erase, so the bootloader is never touched.
• Every image is checked before the first write: its DFU suffix must match the connected bootloader and its md5 the build. Sextant asks first before replacing a different layout.
• Generated firmware keeps the Navigator working, and builds run in a sandbox with no network and no access to your files.
• Nothing is sent to the keyboard unless you ask: the live view, layer moves and lighting previews start only when you turn them on.
• If a flash goes wrong, the Voyager's reset button puts it back in its bootloader, and you can flash again.

Privacy

• No accounts, analytics or telemetry.
• Sextant goes online only to import from Oryx, to download the build tools on the first build, and once a day to ask GitHub whether a newer Sextant is out. Settings › General turns that check off; GitHub sees your IP address and Sextant's version.
• The live view sees key positions, never characters, and pauses in password fields.
• The heatmap is off until you turn it on. It keeps only hourly counts per key, saved in batches of at least 100 presses, in files only your account can read, and it stays on your Mac.

Build from source

Needs Xcode 26 (Swift 6.2 or later).

git clone https://github.com/afrase/Sextant.git
cd Sextant
scripts/bundle            # release build at .build/Sextant.app
open .build/Sextant.app

scripts/check is the quality gate: formatting, lint, layer rules, a warnings-as-errors build and the tests. See CONTRIBUTING.md. The README's stills are rendered offscreen by scripts/readme-images.

Documentation

• docs/guide.md: using Sextant.
• docs/architecture.md: the code design. It's a clean (hexagonal) architecture with one SwiftPM target per layer, so a wrong import fails to compile.
• docs/decisions.md and docs/adr/: every significant decision and why.
• docs/design/ui-spec.md: the UI specification.
• docs/research/00-overview.md: how Oryx, the firmware, the flasher and the live protocol work.
• docs/progress.md: what's done and what's next. Sextant is built with Claude Code, and this is its working log.

To report a vulnerability, follow SECURITY.md rather than opening an issue.

License

MIT.

Third-party software

• QMK firmware (GPL-2.0-or-later) is downloaded at build time, pinned by checksum, and compiled on your Mac. It is not bundled with Sextant. The Arm GNU toolchain, Python and GNU make are downloaded the same way.

• Swift packages, pinned to exact versions:

  Package	License	Used for
  swift-async-algorithms	Apache-2.0	The app
  swift-subprocess	Apache-2.0	The app
  swift-system	Apache-2.0	The app (via swift-subprocess)
  swift-collections	Apache-2.0	The app (via swift-async-algorithms)
  KeyboardShortcuts	MIT	The app (global layer shortcuts)
  MenuBarExtraAccess	MIT	The app (closing the menu bar panel)
  swift-argument-parser	Apache-2.0	The snapshot tool
  swift-clocks	MIT	Tests
  swift-snapshot-testing	MIT	Tests
  swift-issue-reporting, swift-concurrency-extras	MIT	Tests (via swift-clocks)
  swift-custom-dump	MIT	Resolved for swift-snapshot-testing, not built
  swift-syntax	Apache-2.0	Resolved for swift-snapshot-testing, not built
  SwiftLintPlugins	MIT	Linting
  Periphery	MIT	Unused-code report (Tools/)

• docs/research/oryx-examples/ holds the author's own Oryx layout and Oryx's generated source for it, used as golden test data. The zip includes a QMK-built firmware binary, which is GPL-2.0-or-later.

• The screenshots and the tour are rendered offscreen from the author's own layout and contain no ZSA artwork.