diff --git a/Sources/_StringProcessing/RegexDSL/DSL.swift b/Sources/_StringProcessing/RegexDSL/DSL.swift
index 33869b56a..05ee62cff 100644
--- a/Sources/_StringProcessing/RegexDSL/DSL.swift
+++ b/Sources/_StringProcessing/RegexDSL/DSL.swift
@@ -22,6 +22,15 @@ extension String: RegexProtocol {
   }
 }
 
+extension Substring: RegexProtocol {
+  public typealias Match = Substring
+
+  public var regex: Regex<Match> {
+    let atoms = self.map { atom(.char($0)) }
+    return .init(ast: concat(atoms))
+  }
+}
+
 extension Character: RegexProtocol {
   public typealias Match = Substring