diff --git a/clyx_manual.md b/clyx_manual.md
index 0f4d42d..cb0caef 100644
--- a/clyx_manual.md
+++ b/clyx_manual.md
@@ -8,6 +8,8 @@ The Clyx runtime itself allows the programmer to redefine any already defined wo
 
 The conventional source file suffix for Clyx code is `.clx`.
 
+With the reference implementation installed in a POSIX-compatible environment, Clyx program sources may be made executable if they start with a `#!/usr/bin/env clyx` shebang.
+
 ---
 
 ## Conventions