From 53ddba445703cbb7ba8721e8f3895ae83d0d0e0d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Matej=20Jane=C5=BEi=C4=8D?= <janezic.mj@gmail.com>
Date: Sat, 7 Mar 2026 22:10:25 +0100
Subject: [PATCH] feat: add ephvm host

---
 flake.lock                             | 17 +++++++
 flake.nix                              | 14 ++++--
 hosts/ephvm/configuration.nix          | 69 ++++++++++++++++++++++++++
 hosts/ephvm/hardware-configuration.nix | 20 ++++++++
 4 files changed, 116 insertions(+), 4 deletions(-)
 create mode 100644 hosts/ephvm/configuration.nix
 create mode 100644 hosts/ephvm/hardware-configuration.nix

diff --git a/flake.lock b/flake.lock
index 68e69f0..275a1c5 100644
--- a/flake.lock
+++ b/flake.lock
@@ -468,6 +468,22 @@
         "type": "github"
       }
     },
+    "nvim": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1771940146,
+        "narHash": "sha256-z52fdPOWd3hUKKd9IojZ6rFYAgQrdrw/lNKFVdO2jf8=",
+        "ref": "refs/heads/main",
+        "rev": "058c9c730d8d60f482d97b61702561e1ea978847",
+        "revCount": 91,
+        "type": "git",
+        "url": "https://git.janezic.dev/janezicmatej/nvim.git"
+      },
+      "original": {
+        "type": "git",
+        "url": "https://git.janezic.dev/janezicmatej/nvim.git"
+      }
+    },
     "pre-commit": {
       "inputs": {
         "flake-compat": "flake-compat",
@@ -503,6 +519,7 @@
         "nixpkgs": "nixpkgs_3",
         "nixpkgs-master": "nixpkgs-master",
         "nixpkgs-unstable": "nixpkgs-unstable",
+        "nvim": "nvim",
         "stylix": "stylix"
       }
     },
diff --git a/flake.nix b/flake.nix
index b3358a2..8f8b152 100644
--- a/flake.nix
+++ b/flake.nix
@@ -10,10 +10,10 @@
     #   url = "git+https://git.janezic.dev/janezicmatej/.dotfiles.git";
     #   flake = false;
     # };
-    # nvim = {
-    #   url = "git+https://git.janezic.dev/janezicmatej/nvim.git?ref=rewrite";
-    #   flake = false;
-    # };
+    nvim = {
+      url = "git+https://git.janezic.dev/janezicmatej/nvim.git";
+      flake = false;
+    };
 
     nixos-hardware.url = "github:NixOS/nixos-hardware/master";
 
@@ -82,6 +82,11 @@
         iso = mkHost "iso" {
           system = "x86_64-linux";
         };
+
+        ephvm = mkHost "ephvm" {
+          system = "x86_64-linux";
+          user = "matej";
+        };
       };
 
       nixosModules = import ./modules/nixos {
@@ -123,6 +128,7 @@
           packages = [
             pkgs.pre-commit
             pkgs.statix
+            pkgs.qemu
           ];
         };
       }
diff --git a/hosts/ephvm/configuration.nix b/hosts/ephvm/configuration.nix
new file mode 100644
index 0000000..9b1d450
--- /dev/null
+++ b/hosts/ephvm/configuration.nix
@@ -0,0 +1,69 @@
+{
+  pkgs,
+  lib,
+  inputs,
+  config,
+  ...
+}:
+{
+  networking.hostName = "ephvm";
+
+  profiles.base.enable = true;
+
+  vm-guest = {
+    enable = true;
+    headless = true;
+  };
+
+  vm-9p-automount = {
+    enable = true;
+    user = "matej";
+  };
+
+  localisation = {
+    timeZone = "UTC";
+    defaultLocale = "en_US.UTF-8";
+  };
+
+  virtualisation.docker = {
+    enable = true;
+    logDriver = "json-file";
+  };
+
+  # TODO:(@janezicmatej) move neovim dotfiles wiring to a cleaner place
+  home-manager.users.matej = {
+    neovim.dotfiles = inputs.nvim;
+  };
+
+  # writable claude config via 9p
+  fileSystems."/home/matej/.claude" = {
+    device = "claude";
+    fsType = "9p";
+    options = [
+      "trans=virtio"
+      "version=9p2000.L"
+      "nofail"
+      "x-systemd.automount"
+    ];
+  };
+
+  # .claude.json passed via qemu fw_cfg
+  boot.kernelModules = [ "qemu_fw_cfg" ];
+  systemd.services.claude-json = {
+    after = [ "systemd-modules-load.service" ];
+    wants = [ "systemd-modules-load.service" ];
+    wantedBy = [ "multi-user.target" ];
+    serviceConfig = {
+      Type = "oneshot";
+      RemainAfterExit = true;
+      ExecStart = pkgs.writeShellScript "claude-json" ''
+        src="/sys/firmware/qemu_fw_cfg/by_name/opt/claude.json/raw"
+        [ -f "$src" ] || exit 0
+        cp "$src" /home/matej/.claude.json
+        chown matej:users /home/matej/.claude.json
+      '';
+    };
+  };
+
+  system.stateVersion = "25.11";
+}
diff --git a/hosts/ephvm/hardware-configuration.nix b/hosts/ephvm/hardware-configuration.nix
new file mode 100644
index 0000000..2050d4f
--- /dev/null
+++ b/hosts/ephvm/hardware-configuration.nix
@@ -0,0 +1,20 @@
+{
+  lib,
+  pkgs,
+  modulesPath,
+  ...
+}:
+{
+  imports = [
+    (modulesPath + "/profiles/qemu-guest.nix")
+  ];
+
+  fileSystems."/" = {
+    device = "/dev/disk/by-label/nixos";
+    autoResize = true;
+    fsType = "ext4";
+  };
+
+  # image.modules (disk-image.nix) overrides boot loader per variant
+  boot.loader.grub.device = lib.mkDefault "/dev/vda";
+}