diff --git a/src/main/java/com/jnape/palatable/ouroboros/Coalgebra.java b/src/main/java/com/jnape/palatable/ouroboros/Coalgebra.java
new file mode 100644
index 0000000..a048e4a
--- /dev/null
+++ b/src/main/java/com/jnape/palatable/ouroboros/Coalgebra.java
@@ -0,0 +1,15 @@
+package com.jnape.palatable.ouroboros;
+
+import com.jnape.palatable.lambda.functions.Fn1;
+import com.jnape.palatable.lambda.functor.Functor;
+
+/**
+ * A <code>{@link Coalgebra}&lt;A, F&gt;</code> for some carrier type <code>A</code> and some {@link Functor}
+ * <code>F</code> is a morphism <code>A -&gt; F&lt;A&gt;</code>.
+ *
+ * @param <A> the carrier type
+ * @param <F> the {@link Functor} witness
+ */
+@FunctionalInterface
+public interface Coalgebra<A, F extends Functor<A, ?>> extends Fn1<A, F> {
+}