From 693e433fbe626c5e8c444b860f3046e720c51e6d Mon Sep 17 00:00:00 2001
From: alexander <github@systemstart.net>
Date: Thu, 4 Jun 2026 11:54:12 +0200
Subject: [PATCH] feat: mem and vcpu configurable

---
 flake.nix        | 19 ++++++++++++++++---
 modules/base.nix | 14 ++++++++++++--
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/flake.nix b/flake.nix
index 9747c73..40e4b77 100644
--- a/flake.nix
+++ b/flake.nix
@@ -22,7 +22,7 @@
         pi     = { suffix = "-pi";    agentModule = ./modules/agents/pi.nix;    dataDirName = "pi-microvm";    apiKeyVars = [ "ANTHROPIC_API_KEY" "OPENAI_API_KEY" "GEMINI_API_KEY" ]; };
       };
 
-      mkRunnerScript = { pkgs, runner, dataDirName, apiKeyVars, agentName }:
+      mkRunnerScript = { pkgs, runner, dataDirName, apiKeyVars, agentName, defaultMem, defaultVcpu }:
         let
           virtiofsd = pkgs.virtiofsd;
           hostname = "${agentName}-vm";
@@ -32,6 +32,8 @@
         in pkgs.writeShellScriptBin "microvm-run" ''
         set -euo pipefail
         WORK="$(realpath "''${WORK_DIR:-$(pwd)}")"
+        VM_MEM="''${VM_MEM:-${toString defaultMem}}"
+        VM_VCPU="''${VM_VCPU:-${toString defaultVcpu}}"
         RUNTIME="''${XDG_RUNTIME_DIR:-/run/user/$(id -u)}"
         ID="$(cat /proc/sys/kernel/random/uuid)"
 
@@ -256,6 +258,10 @@
           -e "s|${hostname}-virtiofs-agent-home.sock|$AGENT_SOCK|g"
           -e "s|/tmp/${hostname}-cri-storage|$CRI_DIR|g"
           -e "s|${hostname}-virtiofs-cri-storage.sock|$CRI_SOCK|g"
+          # Runtime mem/vcpu override (VM_MEM / VM_VCPU env vars)
+          -e "s| -m ${toString defaultMem} | -m $VM_MEM |g"
+          -e "s| -smp ${toString defaultVcpu} | -smp $VM_VCPU |g"
+          -e "s|size=${toString defaultMem}M|size=''${VM_MEM}M|g"
         )
 
         # Run QEMU with corrected paths
@@ -321,8 +327,15 @@
       packages = forSystems (system: let pkgs = nixpkgs.legacyPackages.${system}; in
         { default = self.packages.${system}.claude; } //
         builtins.mapAttrs (name: flavor: let
-          runner = self.nixosConfigurations."${name}${flavor.suffix}-${system}".config.microvm.runner.qemu;
-        in mkRunnerScript { inherit pkgs runner; inherit (flavor) dataDirName apiKeyVars; agentName = name; }) vmFlavors
+          nixosCfg = self.nixosConfigurations."${name}${flavor.suffix}-${system}".config;
+          runner = nixosCfg.microvm.runner.qemu;
+        in mkRunnerScript {
+          inherit pkgs runner;
+          inherit (flavor) dataDirName apiKeyVars;
+          agentName = name;
+          defaultMem = nixosCfg.claude-vm.agent.mem;
+          defaultVcpu = nixosCfg.claude-vm.agent.vcpu;
+        }) vmFlavors
       );
     };
 }
diff --git a/modules/base.nix b/modules/base.nix
index 9ff075f..8f283ba 100644
--- a/modules/base.nix
+++ b/modules/base.nix
@@ -22,6 +22,16 @@ in
       default = "";
       description = "Agent-specific shell init (runs before launch)";
     };
+    mem = lib.mkOption {
+      type = lib.types.int;
+      default = 8192;
+      description = "VM memory in MB. Overridable at runtime via VM_MEM env var.";
+    };
+    vcpu = lib.mkOption {
+      type = lib.types.int;
+      default = 4;
+      description = "VM vCPU count. Overridable at runtime via VM_VCPU env var.";
+    };
   };
 
   config = {
@@ -31,8 +41,8 @@ in
 
     microvm = {
       hypervisor = "qemu";
-      mem = 4096;
-      vcpu = 4;
+      mem = cfg.mem;
+      vcpu = cfg.vcpu;
 
       writableStoreOverlay = "/nix/.rw-store";