diff --git a/src/modules/sym.txt b/src/modules/sym.txt
index 8d98041..bc7372a 100644
--- a/src/modules/sym.txt
+++ b/src/modules/sym.txt
@@ -497,6 +497,8 @@ because ∵
 qed ∎
 
 // Function and category theory.
+mapsto ↦
+  .long ⟼
 compose ∘
 convolve ∗
 multimap ⊸