diff --git a/test/subtraction/subtraction b/test/subtraction/subtraction
deleted file mode 100644
index 8b13789..0000000
--- a/test/subtraction/subtraction
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/test/subtraction/subtraction.c b/test/subtraction/subtraction.c
new file mode 100644
index 0000000..8894e75
--- /dev/null
+++ b/test/subtraction/subtraction.c
@@ -0,0 +1,8 @@
+#include "unity.h"
+#include "subtraction.h"
+
+void test_subtraction() {
+    TEST_ASSERT_EQUAL_INT(1, subtract(3, 2));
+    TEST_ASSERT_EQUAL_INT(5, subtract(2, -3));
+    TEST_ASSERT_EQUAL_INT(0, subtract(0, 0));
+}