diff --git a/src/test/kotlin/recursion/TailCallTest.java b/src/test/kotlin/recursion/TailCallTest.java
deleted file mode 100644
index f8dd401..0000000
--- a/src/test/kotlin/recursion/TailCallTest.java
+++ /dev/null
@@ -1,31 +0,0 @@
-package recursion;
-
-import org.junit.Test;
-
-import static recursion.TailCalls.done;
-
-public class TailCallTest {
-
-    @Test(expected = UnsupportedOperationException.class)
-    public void tailCallDoesNotSupportResult() {
-        TailCall<Object> tailCall = new TailCall<Object>() {
-
-            @Override
-            public TailCall<Object> apply() {
-                return null;
-            }
-        };
-
-        tailCall.result();
-    }
-
-    @Test(expected = UnsupportedOperationException.class)
-    public void doneDoesNotSupportApply() {
-        done(null).apply();
-    }
-
-    @Test
-    public void TailCallsCoverage() {
-        new TailCalls();
-    }
-}
diff --git a/src/test/kotlin/recursion/TailCallTest.kt b/src/test/kotlin/recursion/TailCallTest.kt
new file mode 100644
index 0000000..9e0ef74
--- /dev/null
+++ b/src/test/kotlin/recursion/TailCallTest.kt
@@ -0,0 +1,20 @@
+package recursion
+
+import org.junit.jupiter.api.Assertions.assertThrows
+import org.junit.jupiter.api.Test
+import recursion.TailCalls.done
+
+class TailCallTest {
+
+    @Test
+    fun `tailCall does not support result`() {
+        val tailCall = TailCall<Any> { null }
+
+        assertThrows(UnsupportedOperationException::class.java) { tailCall.result() }
+    }
+
+    @Test
+    fun `done does not support apply`() {
+        assertThrows(UnsupportedOperationException::class.java) { done<Any>(null).apply() }
+    }
+}