diff --git a/test/signature.test.ts b/test/signature.test.ts
index 5cfb1fe..89c316e 100644
--- a/test/signature.test.ts
+++ b/test/signature.test.ts
@@ -1,4 +1,4 @@
-import {test, expect} from 'bun:test'
+import {test, expect, describe} from 'bun:test'
 
 import {signature} from '../index'
 import {derive_keypair, gen_keypair, sign, verify} from "../src/signature";
@@ -53,3 +53,43 @@ test('tampered signature', async () => {
 
     expect(verification).toBe(false)
 })
+
+describe('Derive array', () => {
+    test('Case derive key and use it', async () => {
+        const data = new Uint8Array([1])
+        const kp = await derive_keypair(data)
+
+        const message = new Uint8Array(12)
+        const sig = await sign(message, kp[0])
+        const verif = await verify(message, kp[1], sig)
+
+        expect(verif).toBeTrue()
+    })
+
+    test('Same derive, same key', async () => {
+        const data = new Uint8Array([1,2,3])
+
+        const k1 = await derive_keypair(data)
+        const k2 = await derive_keypair(data)
+
+        const message = new Uint8Array(12)
+        const sig = await sign(message, k1[0])
+        const verif = await verify(message, k2[1], sig)
+
+        expect(verif).toBeTrue()
+    })
+
+    test('Different input, different key', async () => {
+        const d1 = new Uint8Array([1,2,3])
+        const d2 = new Uint8Array([3,2,1])
+
+        const k1 = await derive_keypair(d1)
+        const k2 = await derive_keypair(d2)
+
+        const message = new Uint8Array(12)
+        const sig = await sign(message, k1[0])
+        const verif = await verify(message, k2[1], sig)
+
+        expect(verif).toBeFalse()
+    })
+})