diff --git a/prototype/DoubtTests/DiffTests.swift b/prototype/DoubtTests/DiffTests.swift
index 45eb6fb26..455b949ac 100644
--- a/prototype/DoubtTests/DiffTests.swift
+++ b/prototype/DoubtTests/DiffTests.swift
@@ -41,5 +41,5 @@ private let c = Term.In(.Leaf(.Literal("c", [])))
 private let d = Term.In(.Leaf(.Literal("d", [])))
 
 
-import Doubt
+@testable import Doubt
 import XCTest