diff --git a/hosts/development.nix b/hosts/development.nix
index 7320d9a..98fe267 100644
--- a/hosts/development.nix
+++ b/hosts/development.nix
@@ -53,6 +53,10 @@
         # Glasgow
         SUBSYSTEM=="usb", ATTRS{idVendor}=="20b7", ATTRS{idProduct}=="9db1", MODE="0660", GROUP="plugdev"
 
+        # Cynthion
+        SUBSYSTEM=="usb", ATTRS{idVendor}=="1d50", ATTRS{idProduct}=="615b", MODE="0660", GROUP="plugdev"
+        SUBSYSTEM=="usb", ATTRS{idVendor}=="1d50", ATTRS{idProduct}=="615c", MODE="0660", GROUP="plugdev"
+
         # Shared V-USB VID:PID for use with various homebrew stuff
         ATTRS{idVendor}=="16c0", ATTRS{idProduct}=="05dc", MODE="0660", GROUP="plugdev"
         ATTRS{idVendor}=="16c0", ATTRS{idProduct}=="05df", MODE="0660", GROUP="plugdev"