diff --git a/src/registries/sensors.rs b/src/registries/sensors.rs
new file mode 100644
index 0000000..3508b2e
--- /dev/null
+++ b/src/registries/sensors.rs
@@ -0,0 +1,16 @@
+use futures::{Future, Stream};
+
+pub struct Sensors {
+    
+}
+
+
+// Implementing Sensors.
+//
+// Given the coroutine/task split stays as it is - Sensor input to machine update being one,
+// machine update signal to actor doing thing being another, a Sensor implementation would send a
+// Stream of futures - each future being an atomic Machine update.
+#[async_trait]
+pub trait Sensor: Stream<Item = Box<dyn Future<Output = ()>>> {
+    async fn setup() -> Self;
+}