diff --git a/conmorfeusz/conmorfeusz/cli/__init__.py b/conmorfeusz/conmorfeusz/cli/__init__.py
index a71d904..ad5f77b 100644
--- a/conmorfeusz/conmorfeusz/cli/__init__.py
+++ b/conmorfeusz/conmorfeusz/cli/__init__.py
@@ -14,9 +14,8 @@ from conmorfeusz.server import StandaloneApplication
 @click.option('--ccpl-port', default=3000, help='Port which internal concraft-pl server will be listening on.')
 @click.option('--ccpl-model', default=None, help='Model used by concraft-pl. It will fallback to CONCRAFT_PL_MODEL envvar if not specified.')
 @click.option('--ccpl-bin', default=None, help='Concraft-pl binary file. It will fallback to CONCRAFT_PL_BIN envvar if not specified.')
-@click.option('--ccpl-core-num', default=1, help='Number of cores used to run Concraft-pl logic.')
-@click.option('--ccpl-alloc-size', default=64, help='Allocation size for Concraft-pl.')
-def run(host, port, workers, ccpl_port, ccpl_model, ccpl_bin, ccpl_core_num, ccpl_alloc_size):
+@click.option("--ccpl-rts", default="-A4M -N4", help='Runtime system configuration for Concraft-pl VM.')
+def run(host, port, workers, ccpl_port, ccpl_model, ccpl_bin, ccpl_rts):
   """
   Glues all services together and starts the holistic app.
   """
@@ -30,7 +29,7 @@ def run(host, port, workers, ccpl_port, ccpl_model, ccpl_bin, ccpl_core_num, ccp
   if ccpl_bin is None:
     raise Exception("Concraft-pl binary file must be specified either by --ccpl-bin option or by CONCRAFT_PL_BIN environment variable")
 
-  concraft_cfg = (ccpl_model, ccpl_bin, ccpl_port, ccpl_core_num, ccpl_alloc_size)
+  concraft_cfg = (ccpl_model, ccpl_bin, ccpl_port, ccpl_rts.split())
 
   with ccpl.start_server(*concraft_cfg):    
     options = {
diff --git a/conmorfeusz/conmorfeusz/concraft/__init__.py b/conmorfeusz/conmorfeusz/concraft/__init__.py
index c834814..2431a94 100644
--- a/conmorfeusz/conmorfeusz/concraft/__init__.py
+++ b/conmorfeusz/conmorfeusz/concraft/__init__.py
@@ -86,7 +86,7 @@ class Concraft(object):
 
 class Server(object):
     def __init__(self, model_path, concraft_path="concraft-pl", port=3000,
-            core_num=1, allocation_size=64):
+            runtimeArgs=[]):
         """
         Start a Concraft-pl server instance in the background.
 
@@ -105,8 +105,7 @@ class Server(object):
         """
         self.port = port
         self.concraft_server = Popen([concraft_path, 'server',
-            '--port={}'.format(port), '-i', model_path, '+RTS',
-            '-N{}'.format(core_num), '-A{}M'.format(allocation_size),],
+            '--port={}'.format(port), '-i', model_path, '+RTS', *runtimeArgs],
             stdin=PIPE, stdout=PIPE, stderr=PIPE)
         # print(u"Concraft model " + model_path + u" loading...")
         loaded = False
diff --git a/module.nix b/module.nix
index 615be5e..85c3089 100644
--- a/module.nix
+++ b/module.nix
@@ -6,20 +6,6 @@ self: {
   ...
 }: let
   cfg = config.services.conmorfeusz;
-
-  # Helper function to convert attrset to CLI arguments
-  # { host = "0.0.0.0"; port = 8888; } -> "--host '0.0.0.0' --port '8888'"
-  attrsToArgs = attrs:
-    lib.concatStringsSep " " (
-      lib.mapAttrsToList (name: value: "--${name} ${lib.escapeShellArg (toString value)}") attrs
-    );
-
-  # Helper function to convert attrset to CLI arguments with prefix
-  # { port = 3000; bin = "..."; } -> "--ccpl-port '3000' --ccpl-bin '...'"
-  attrsToArgsWithPrefix = prefix: attrs:
-    lib.concatStringsSep " " (
-      lib.mapAttrsToList (name: value: "--${prefix}-${name} ${lib.escapeShellArg (toString value)}") attrs
-    );
 in {
   options.services.conmorfeusz = {
     enableMorfeusz = lib.mkEnableOption "Morfeusz in environment.systemPackages";
@@ -91,8 +77,14 @@ in {
         serviceConfig = {
           Type = "simple";
           ExecStart = let
-            mainArgs = attrsToArgs cfg.conmorfeusz.config;
-            ccplArgs = attrsToArgsWithPrefix "ccpl" cfg.conmorfeusz.concraft-pl;
+            mainArgs = lib.cli.toGNUCommandLineShell {} cfg.conmorfeusz.config;
+
+            ccplArgs =
+              lib.cli.toGNUCommandLineShell {
+                mkOptionName = k: "--ccpl-${k}";
+              }
+              cfg.conmorfeusz.concraft-pl;
+
             allArgs = lib.concatStringsSep " " (lib.filter (s: s != "") [mainArgs ccplArgs]);
           in "${self.packages.${pkgs.system}.conmorfeusz}/bin/conmorfeusz ${allArgs}";