NixOS packaging and modules for PiKVM's kvmd. Run a PiKVM on a stock NixOS Raspberry Pi.

Not affiliated with the PiKVM project.

Two variants for the Raspberry Pi 4 are supported:

• v2-hdmi-rpi4: CSI capture via the TC358743 HDMI→CSI bridge.
• v2-hdmiusb-rpi4: USB UVC capture dongle (e.g. MS2109), on any USB port.

Both build a flashable SD image and have been tested on real hardware.

• packages.${system}.{default,kvmd}: the kvmd package (default is kvmd).
• nixosModules.{default,kvmd}: the daemon set (kvmd + otg/media/pst/janus/nginx and optional vnc/ipmi/nbd/webterm); default is kvmd.
• nixosModules.<variant> (v2-hdmi-rpi4, v2-hdmiusb-rpi4): the Pi 4 hardware profile (kernel patches, dwc2, capture); sets services.kvmd.variant, so pair it with nixosModules.kvmd.
• nixosConfigurations.<variant>: ready-to-flash SD images.

Build an SD image:

nix build github:aostanin/kvmd.nix#nixosConfigurations.v2-hdmi-rpi4.config.system.build.sdImage

Or compose it into your own host:

{
  inputs.kvmd.url = "github:aostanin/kvmd.nix";

  outputs = { nixpkgs, kvmd, ... }: {
    nixosConfigurations.mykvm = nixpkgs.lib.nixosSystem {
      system = "aarch64-linux";
      modules = [
        kvmd.nixosModules.default
        kvmd.nixosModules.v2-hdmi-rpi4
        {
          services.kvmd = {
            enable = true;

            ocrLanguages = ["eng" "rus"];

            htpasswdFile = "/run/secrets/kvmd-htpasswd";
            vnc = {
              enable = true;
              passwordFile = "/run/secrets/kvmd-vncpasswd";
            };
            ipmi = {
              enable = true;
              passwordFile = "/run/secrets/kvmd-ipmipasswd";
            };

            overrideConfig = {
              kvmd.streamer.resolution.default = "1280x720";
            };
          };
        }
      ];
    };
  };
}

The nixosConfigurations ship insecure defaults for first boot. Before putting a box on a network you must change:

• Root password (pikvm) and root SSH login.
• The kvmd web / VNC / IPMI credentials. These default to the upstream example files (admin/admin). Point them at your own:

services.kvmd.htpasswdFile      = "/run/secrets/kvmd-htpasswd";   # user:{SSHA512}…
services.kvmd.vnc.passwordFile  = "/run/secrets/kvmd-vncpasswd";  # plaintext, one per line
services.kvmd.ipmi.passwordFile = "/run/secrets/kvmd-ipmipasswd"; # login:password

This repository's Nix code is MIT (see LICENSE). It only packages and configures upstream software consumed as flake inputs:

• pikvm/kvmd: GPL-3.0-or-later, © Maxim Devaev; the resulting kvmd package is therefore GPL-3.0-or-later.
• pikvm/packages: kernel and janus.js patches applied to the RPi kernel / Janus assets.