diff --git a/runtime/syntax/swift.yaml b/runtime/syntax/swift.yaml
index b6e46cf32..4874132f8 100644
--- a/runtime/syntax/swift.yaml
+++ b/runtime/syntax/swift.yaml
@@ -2,6 +2,7 @@ filetype: swift
 
 detect:
     filename: "\\.swift$"
+    header: "^#!.*bin/(env +)?swift( |$)"
 
 rules: