feat(ollama): add ollama service

users/modules/ollama.nix

@@ -0,0 +1,25 @@
+{
+  config,
+  lib,
+  ...
+}:
+with lib; let
+  cfg = config.modules.ollama;
+in {
+  options.modules.ollama = {
+    enable = mkEnableOption "Enables Ollama";
+    gpu = mkOption {
+      type = types.nullOr types.enum ["none" "amd" "nvidia"];
+      example = "amd";
+      default = "none";
+      description = "Which type of GPU should be used for hardware acceleration";
+    };
+  };
+
+  config.services.ollama = mkIf cfg.enable {
+    inherit (cfg) enable;
+    environmentVariables = {
+      OLLAMA_CONTEXT_LENGTH = "8192";
+    };
+  };
+}