diff --git a/architecture.py b/architecture.py
index 61f0d84..c8565fe 100644
--- a/architecture.py
+++ b/architecture.py
@@ -1,18 +1,18 @@
 import os
 
 import distribution
+import subsystem
 
 X86 = 'x86_64'
 I86 = 'i686'
 
 
 class Architecture:
-    def __init__(self, name, bits):
+    def __init__(self, name, bits, subsystems):
         self.name = name
         self.bits = bits
         self.distribution = distribution.Distribution(self)
-        # TODO subsystems
-        self.subsystems = {}
+        self.subsystems = {s: subsystem.SubSystem(self, s) for s in subsystems}
 
     def __str__(self):
         lines = [
@@ -21,7 +21,12 @@ class Architecture:
         return os.linesep.join(lines)
 
 
+x86 = Architecture(X86, 64, [subsystem.MAIN,
+                             'clang64', 'mingw64', 'ucrt64'])
+i86 = Architecture(I86, 32, [subsystem.MAIN,
+                             'clang32', 'mingw32'])
+
 ARCHITECTURES = {
-    X86: Architecture(X86, 64),
-    I86: Architecture(I86, 32),
+    X86: x86,
+    I86: i86,
 }
diff --git a/arguments.py b/arguments.py
index 768a5e2..482a885 100644
--- a/arguments.py
+++ b/arguments.py
@@ -86,3 +86,4 @@ compression applying to archive
 D = parse()
 
 architectures = D[ARCHITECTURES]
+subsystems = D[SUBSYSTEMS]
diff --git a/remote.py b/remote.py
index 1886111..68e9f5e 100644
--- a/remote.py
+++ b/remote.py
@@ -11,14 +11,13 @@ import repository
 class Remote(repository.Repository):
     def __init__(self, args):
         super().__init__(args[arguments.REMOTE])
-        self.subsystems = args[arguments.SUBSYSTEMS]
         self.load()
 
     def load(self):
         archives = {}
         c = {}
         for architecture in self.architectures:
-            subsystems = msys.get_subsystems(architecture, self.subsystems)
+            subsystems = architecture.subsystems.keys()
             location = os.path.join(self.location,
                                     msys.get_distribution(architecture))
             archives[architecture] = hypertext.HyperText(location).archive
diff --git a/synchronization.py b/synchronization.py
index 27956e0..3899624 100644
--- a/synchronization.py
+++ b/synchronization.py
@@ -17,8 +17,7 @@ class Synchronization:
 
     def run(self):
         for architecture in self.remote.architectures:
-            for subsystem in msys.get_subsystems(architecture,
-                                                 self.remote.subsystems):
+            for subsystem in architecture.subsystems.keys():
                 catalog = self.remote.catalogs[architecture][subsystem]
                 path = msys.get_subsystem(architecture, subsystem)
                 for _, package in sorted(catalog.packages.items()):