diff --git a/HostProp.hs b/HostProp.hs
index 1db3dcf..7a98c5a 100644
--- a/HostProp.hs
+++ b/HostProp.hs
@@ -25,7 +25,6 @@ getProperties "clam" =
 	, Apt.stdSourcesList Apt.Unstable `onChange` Apt.upgrade
 	, Apt.installed ["etckeeper"]
 	, Apt.installed ["ssh"]
-	, Apt.installed ["git", "myrepos"]
 	, GitHome.installedFor "root"
 	-- Harden the system, but only once root's authorized_keys
 	-- is safely in place.
@@ -38,7 +37,6 @@ getProperties "clam" =
 	, lineInFile "/etc/sudoers" "joey ALL=(ALL:ALL) ALL"
 	, GitHome.installedFor "joey"
 	-- Clam is a tor bridge.
-	, Apt.installed ["tor"]
 	, Tor.isBridge
 	-- Should come last as it reboots.
 	, Apt.installed ["systemd-sysv"] `onChange` Reboot.scheduled "+10"
diff --git a/Property.hs b/Property.hs
index 3243d27..c4db8bc 100644
--- a/Property.hs
+++ b/Property.hs
@@ -147,6 +147,9 @@ property `onChange` hook = IOProperty (propertyDesc property) $ do
 			return $ combineResult r r'
 		_ -> return r
 
+requires :: Property -> Property -> Property
+x `requires` y = combineProperties (propertyDesc x) [y, x]
+
 {- Makes a Property only be performed when a test succeeds. -}
 check :: IO Bool -> Property -> Property
 check c property = IOProperty (propertyDesc property) $ ifM c
diff --git a/Property/GitHome.hs b/Property/GitHome.hs
index 217e129..09d2132 100644
--- a/Property/GitHome.hs
+++ b/Property/GitHome.hs
@@ -11,11 +11,13 @@ import Utility.SafeCommand
 import Utility.Directory
 import Utility.Monad
 import Utility.Exception
+import qualified Property.Apt as Apt
 
 {- Clones Joey Hess's git home directory, and runs its fixups script. -}
 installedFor :: UserName -> Property
 installedFor user = check (not <$> hasGitDir user) $ 
 	IOProperty ("githome " ++ user) (go =<< homedir user)
+		`requires` Apt.installed ["git", "myrepos"]
   where
  	go Nothing = noChange
 	go (Just home) = do
diff --git a/Property/Tor.hs b/Property/Tor.hs
index bebf076..b26ba68 100644
--- a/Property/Tor.hs
+++ b/Property/Tor.hs
@@ -1,21 +1,18 @@
 module Property.Tor where
 
-import Control.Applicative
-import Control.Monad
-import System.FilePath
-
 import Property
-import Property.User
 import Utility.SafeCommand
-import Utility.Exception
+import qualified Property.Apt as Apt
 
 isBridge :: Property
-isBridge = fileHasContent "/etc/tor/torrc"
-	[ "SocksPort 0"
-	, "ORPort 443"
-	, "BridgeRelay 1"
-	, "Exitpolicy reject *:*"
-	] `onChange` restartTor
+isBridge = setup `requires` Apt.installed ["tor"]
+  where
+	setup = fileHasContent "/etc/tor/torrc"
+		[ "SocksPort 0"
+		, "ORPort 443"
+		, "BridgeRelay 1"
+		, "Exitpolicy reject *:*"
+		] `onChange` restartTor
 
 restartTor :: Property
 restartTor = cmdProperty "service" [Param "tor", Param "restart"]