Assisted-by: Claude Opus 5.5 via Claude Code

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+# keyboards
+
+Keyboard designs and firmware keymaps:
+
+| Directory | What it is |
+|---|---|
+| `alpheus/` | A portable unibody keyboard designed in [Ergogen][ergogen]; see its [README](alpheus/README.md) |
+| `Model100/` | A [Kaleidoscope][kaleidoscope] sketch for the Keyboardio Model 100 |
+| `qmk/` | A [QMK userspace][qmk-userspace] with a keymap for the splitkb Kyria |
+
+The Nix flake's dev shell provides `ergogen`.
+
+To build the Model 100 firmware, copy `Model100/Model100.ino` over
+`examples/Devices/Keyboardio/Model100/Model100.ino` in a Kaleidoscope
+checkout.
+
+To build the Kyria firmware, point QMK at the userspace and compile it:
+
+```sh
+qmk config user.overlay_dir="$PWD/qmk"
+qmk userspace-compile
+```
+
+[ergogen]: https://ergogen.xyz
+[kaleidoscope]: https://github.com/keyboardio/Kaleidoscope
+[qmk-userspace]: https://docs.qmk.fm/newbs_external_userspace