diff --git a/04-recursion/02-unwinding/sum-up-to-test.js b/04-recursion/02-unwinding/sum-up-to-test.js
index 0df1a4ec..deb4e136 100644
--- a/04-recursion/02-unwinding/sum-up-to-test.js
+++ b/04-recursion/02-unwinding/sum-up-to-test.js
@@ -1,3 +1,5 @@
+const sumUpTo = require('./sum-up-to');
+
 test('Summing up positive integers', () => {
   expect(sumUpTo(5)).toBe(15);
   expect(sumUpTo(10)).toBe(55);