diff --git a/quartz/src/androidTest/java/com/vitorpamplona/quartz/crypto/nip01/Nip01Test.kt b/quartz/src/androidTest/java/com/vitorpamplona/quartz/crypto/nip01/Nip01Test.kt
new file mode 100644
index 000000000..5c93f1cbb
--- /dev/null
+++ b/quartz/src/androidTest/java/com/vitorpamplona/quartz/crypto/nip01/Nip01Test.kt
@@ -0,0 +1,93 @@
+/**
+ * Copyright (c) 2024 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.crypto.nip01
+
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.vitorpamplona.quartz.encoders.hexToByteArray
+import com.vitorpamplona.quartz.encoders.toHexKey
+import fr.acinq.secp256k1.Secp256k1
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNotEquals
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import org.junit.runner.RunWith
+import java.security.SecureRandom
+
+@RunWith(AndroidJUnit4::class)
+class Nip01Test {
+    private val nip01 = Nip01(Secp256k1.get(), SecureRandom())
+    private val privateKey = "f410f88bcec6cbfda04d6a273c7b1dd8bba144cd45b71e87109cfa11dd7ed561".hexToByteArray()
+
+    @Test
+    fun testGetPublicFromPrivateKey() {
+        assertEquals(
+            "7d4b8806f1fd713c287235411bf95aa81b7242ead892733ec84b3f2719845be6",
+            nip01.pubkeyCreate(privateKey).toHexKey(),
+        )
+    }
+
+    @Test
+    fun testDeterministicSign() {
+        assertEquals(
+            "1484d0e0bd62165e822e31f1f4cc8e1ce8e20c30a060e24fb0ecd7baf7c624f661fb7a3e4f0ddb43018e5f0b4892c929af64d8b7a86021aa081ec8231e3dfa37",
+            nip01.signDeterministic(nip01.sha256("Test".toByteArray()), privateKey).toHexKey(),
+        )
+    }
+
+    @Test
+    fun testSha256() {
+        assertEquals(
+            "532eaabd9574880dbf76b9b8cc00832c20a6ec113d682299550d7a6e0f345e25",
+            nip01.sha256("Test".toByteArray()).toHexKey(),
+        )
+    }
+
+    @Test
+    fun testDeterministicVerify() {
+        assertTrue(
+            nip01.verify(
+                "1484d0e0bd62165e822e31f1f4cc8e1ce8e20c30a060e24fb0ecd7baf7c624f661fb7a3e4f0ddb43018e5f0b4892c929af64d8b7a86021aa081ec8231e3dfa37".hexToByteArray(),
+                nip01.sha256("Test".toByteArray()),
+                nip01.pubkeyCreate(privateKey),
+            ),
+        )
+    }
+
+    @Test
+    fun testNonDeterministicSign() {
+        assertNotEquals(
+            "1484d0e0bd62165e822e31f1f4cc8e1ce8e20c30a060e24fb0ecd7baf7c624f661fb7a3e4f0ddb43018e5f0b4892c929af64d8b7a86021aa081ec8231e3dfa37",
+            nip01.sign(nip01.sha256("Test".toByteArray()), privateKey).toHexKey(),
+        )
+    }
+
+    @Test
+    fun testNonDeterministicSignVerify() {
+        val signature = nip01.sign(nip01.sha256("Test".toByteArray()), privateKey)
+        assertTrue(
+            nip01.verify(
+                signature,
+                nip01.sha256("Test".toByteArray()),
+                nip01.pubkeyCreate(privateKey),
+            ),
+        )
+    }
+}
diff --git a/quartz/src/main/java/com/vitorpamplona/quartz/crypto/nip01/Nip01.kt b/quartz/src/main/java/com/vitorpamplona/quartz/crypto/nip01/Nip01.kt
index 3bbf58ea3..eb5159735 100644
--- a/quartz/src/main/java/com/vitorpamplona/quartz/crypto/nip01/Nip01.kt
+++ b/quartz/src/main/java/com/vitorpamplona/quartz/crypto/nip01/Nip01.kt
@@ -38,9 +38,14 @@ class Nip01(
     fun sign(
         data: ByteArray,
         privKey: ByteArray,
-        auxrand32: ByteArray? = null,
+        auxrand32: ByteArray? = random(32),
     ): ByteArray = secp256k1.signSchnorr(data, privKey, auxrand32)
 
+    fun signDeterministic(
+        data: ByteArray,
+        privKey: ByteArray,
+    ): ByteArray = secp256k1.signSchnorr(data, privKey, null)
+
     fun verify(
         signature: ByteArray,
         hash: ByteArray,