diff --git a/src/main.rs b/src/main.rs
index 19ae35c..25bc642 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -17,6 +17,7 @@ mod error;
 mod machine;
 mod connection;
 mod registries;
+mod network;
 
 use signal_hook::iterator::Signals;
 
diff --git a/src/network.rs b/src/network.rs
index c6340f3..e9d0e6b 100644
--- a/src/network.rs
+++ b/src/network.rs
@@ -19,7 +19,15 @@ impl Network {
     ///
     /// Idea being that bffh builds an event network that filters an incoming event into an
     /// the appropiate (sub)set of signal handlers based on pretty dynamic configuration.
-    pub fn filter<S: Signal, F: Fn() -> bool>(&mut self) {
+    pub fn filter<B, S: Signal<Item=B>, F: Fn(&B) -> bool>(&mut self, ) {
         unimplemented!()
     }
 }
+
+enum Event {
+
+}
+
+trait Filter<S> {
+    fn filter(&self, f: Fn(&S) -> bool);
+}