diff --git a/src/lib/Hydra/Controller/Root.pm b/src/lib/Hydra/Controller/Root.pm
index 9dd56964..a5ecb312 100644
--- a/src/lib/Hydra/Controller/Root.pm
+++ b/src/lib/Hydra/Controller/Root.pm
@@ -246,18 +246,35 @@ sub get_builds : Chained('/') PathPart('') CaptureArgs(0) {
 sub robots_txt : Path('robots.txt') {
     my ($self, $c) = @_;
 
+    sub uri_for {
+        my ($controller, $action, @args) = @_;
+        return $c->uri_for($c->controller($controller)->action_for($action), @args)->path;
+    }
+
+    sub channelUris {
+        my ($controller, $bindings) = @_;
+        return
+            ( "Disallow: " . uri_for($controller, 'closure', $bindings, "*")
+            , "Disallow: " . uri_for($controller, 'manifest', $bindings)
+            , "Disallow: " . uri_for($controller, 'nar', $bindings, "*")
+            , "Disallow: " . uri_for($controller, 'pkg', $bindings, "*")
+            , "Disallow: " . uri_for($controller, 'nixexprs', $bindings)
+            );
+    }
+
     # Put actions that are expensive or not useful for indexing in
     # robots.txt.  Note: wildcards are not universally supported in
     # robots.txt, but apparently Google supports them.
     my @rules =
         ( "User-agent: *"
-        , "Disallow: /*/nix/closure/*" 
-        , "Disallow: /*/channel/*/MANIFEST.bz2" 
-        , "Disallow: /*/nar/*" 
-        , "Disallow: /*.nixpkg" 
-        , "Disallow: /build/*/buildtime-deps" 
-        , "Disallow: /build/*/runtime-deps" 
-        , "Disallow: /build/*/nixlog/*/tail" 
+        , "Disallow: " . uri_for('Build', 'buildtimedeps', ["*"])
+        , "Disallow: " . uri_for('Build', 'runtimedeps', ["*"])
+        , "Disallow: " . uri_for('Build', 'view_nixlog', ["*"], "*/tail")
+        , channelUris('Root', ["*"])
+        , channelUris('Project', ["*", "*"])
+        , channelUris('Jobset', ["*", "*", "*"])
+        , channelUris('Job', ["*", "*", "*", "*"])
+        , channelUris('Build', ["*"])
         );
     
     $c->stash->{'plain'} = { data => join("\n", @rules) };