diff --git a/Sources/Prototypes/PEG/PEGInterpreter.swift b/Sources/Prototypes/PEG/PEGInterpreter.swift
index ef849c3c9..fb736ee3d 100644
--- a/Sources/Prototypes/PEG/PEGInterpreter.swift
+++ b/Sources/Prototypes/PEG/PEGInterpreter.swift
@@ -9,7 +9,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-import XCTest
 extension PEG {
   struct Grammar {
     var environment: Dictionary<String, Pattern>