diff --git a/library/blake2/api/blake2.api b/library/blake2/api/blake2.api
index f1dd422..a667be7 100644
--- a/library/blake2/api/blake2.api
+++ b/library/blake2/api/blake2.api
@@ -1,10 +1,14 @@
 public abstract class org/kotlincrypto/macs/blake2/BLAKE2Mac : org/kotlincrypto/core/mac/Mac {
 	public synthetic fun <init> (Lorg/kotlincrypto/macs/blake2/BLAKE2Mac$Engine;Lkotlin/jvm/internal/DefaultConstructorMarker;)V
 	public synthetic fun <init> (Lorg/kotlincrypto/macs/blake2/BLAKE2Mac;Lkotlin/jvm/internal/DefaultConstructorMarker;)V
-	public synthetic fun <init> ([BI[BLorg/kotlincrypto/hash/blake2/BLAKE2Digest$KeyedHashFactory;Lkotlin/jvm/internal/DefaultConstructorMarker;)V
+	public synthetic fun <init> ([BI[BLorg/kotlincrypto/macs/blake2/BLAKE2Mac$DigestFactory;Lkotlin/jvm/internal/DefaultConstructorMarker;)V
 	public abstract fun copy ()Lorg/kotlincrypto/macs/blake2/BLAKE2Mac;
 }
 
+protected abstract interface class org/kotlincrypto/macs/blake2/BLAKE2Mac$DigestFactory {
+	public abstract fun newInstance (II[B[B)Lorg/kotlincrypto/hash/blake2/BLAKE2Digest;
+}
+
 public final class org/kotlincrypto/macs/blake2/BLAKE2b : org/kotlincrypto/macs/blake2/BLAKE2Mac {
 	public fun <init> ([BI)V
 	public fun <init> ([BI[B)V
diff --git a/library/blake2/api/blake2.klib.api b/library/blake2/api/blake2.klib.api
index d519ecf..b9c0a2f 100644
--- a/library/blake2/api/blake2.klib.api
+++ b/library/blake2/api/blake2.klib.api
@@ -21,8 +21,12 @@ final class org.kotlincrypto.macs.blake2/BLAKE2s : org.kotlincrypto.macs.blake2/
 }
 
 sealed class org.kotlincrypto.macs.blake2/BLAKE2Mac : org.kotlincrypto.core.mac/Mac { // org.kotlincrypto.macs.blake2/BLAKE2Mac|null[0]
-    constructor <init>(kotlin/ByteArray, kotlin/Int, kotlin/ByteArray?, org.kotlincrypto.hash.blake2/BLAKE2Digest.KeyedHashFactory<*>) // org.kotlincrypto.macs.blake2/BLAKE2Mac.<init>|<init>(kotlin.ByteArray;kotlin.Int;kotlin.ByteArray?;org.kotlincrypto.hash.blake2.BLAKE2Digest.KeyedHashFactory<*>){}[0]
+    constructor <init>(kotlin/ByteArray, kotlin/Int, kotlin/ByteArray?, org.kotlincrypto.macs.blake2/BLAKE2Mac.DigestFactory) // org.kotlincrypto.macs.blake2/BLAKE2Mac.<init>|<init>(kotlin.ByteArray;kotlin.Int;kotlin.ByteArray?;org.kotlincrypto.macs.blake2.BLAKE2Mac.DigestFactory){}[0]
     constructor <init>(org.kotlincrypto.macs.blake2/BLAKE2Mac) // org.kotlincrypto.macs.blake2/BLAKE2Mac.<init>|<init>(org.kotlincrypto.macs.blake2.BLAKE2Mac){}[0]
 
     abstract fun copy(): org.kotlincrypto.macs.blake2/BLAKE2Mac // org.kotlincrypto.macs.blake2/BLAKE2Mac.copy|copy(){}[0]
+
+    abstract fun interface DigestFactory { // org.kotlincrypto.macs.blake2/BLAKE2Mac.DigestFactory|null[0]
+        abstract fun newInstance(kotlin/Int, kotlin/Int, kotlin/ByteArray?, kotlin/ByteArray?): org.kotlincrypto.hash.blake2/BLAKE2Digest // org.kotlincrypto.macs.blake2/BLAKE2Mac.DigestFactory.newInstance|newInstance(kotlin.Int;kotlin.Int;kotlin.ByteArray?;kotlin.ByteArray?){}[0]
+    }
 }
diff --git a/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2Mac.kt b/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2Mac.kt
index 6e9568f..ebb56c0 100644
--- a/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2Mac.kt
+++ b/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2Mac.kt
@@ -16,7 +16,6 @@
 package org.kotlincrypto.macs.blake2
 
 import org.kotlincrypto.core.Algorithm
-import org.kotlincrypto.core.InternalKotlinCryptoApi
 import org.kotlincrypto.core.mac.Mac
 import org.kotlincrypto.hash.blake2.BLAKE2Digest
 
@@ -34,22 +33,32 @@ public sealed class BLAKE2Mac: Mac {
         key: ByteArray,
         bitStrength: Int,
         personalization: ByteArray?,
-        factory: BLAKE2Digest.KeyedHashFactory<*>,
+        factory: DigestFactory,
     ): this(Engine(key, bitStrength, personalization, factory))
 
     protected constructor(other: BLAKE2Mac): super(other)
 
+    protected fun interface DigestFactory {
+
+        @Throws(IllegalArgumentException::class)
+        public fun newInstance(
+            bitStrength: Int,
+            keyLength: Int,
+            salt: ByteArray?,
+            personalization: ByteArray?,
+        ): BLAKE2Digest
+    }
+
     private constructor(engine: Engine): super(engine.algorithm(), engine)
 
     public abstract override fun copy(): BLAKE2Mac
 
-    @OptIn(InternalKotlinCryptoApi::class)
     private class Engine: Mac.Engine, Algorithm {
 
         private val bitStrength: Int
         private val keyBlock: ByteArray
         private val personalization: ByteArray?
-        private val factory: BLAKE2Digest.KeyedHashFactory<*>
+        private val factory: DigestFactory
         private var digest: BLAKE2Digest
 
         @Throws(IllegalArgumentException::class)
@@ -57,11 +66,11 @@ public sealed class BLAKE2Mac: Mac {
             key: ByteArray,
             bitStrength: Int,
             personalization: ByteArray?,
-            factory: BLAKE2Digest.KeyedHashFactory<*>,
+            factory: DigestFactory,
         ): super(key) {
             this.bitStrength = bitStrength
             this.personalization = personalization?.copyOf()
-            this.digest = factory.keyedHashInstance(
+            this.digest = factory.newInstance(
                 bitStrength = bitStrength,
                 keyLength = key.size,
                 salt = null,
@@ -95,7 +104,7 @@ public sealed class BLAKE2Mac: Mac {
 
         override fun reset(newKey: ByteArray) {
             val oldDigest = digest
-            this.digest = factory.keyedHashInstance(
+            this.digest = factory.newInstance(
                 bitStrength = bitStrength,
                 keyLength = newKey.size,
                 salt = null,
diff --git a/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2b.kt b/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2b.kt
index 4b0fe43..74424aa 100644
--- a/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2b.kt
+++ b/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2b.kt
@@ -15,6 +15,8 @@
  **/
 package org.kotlincrypto.macs.blake2
 
+import org.kotlincrypto.core.InternalKotlinCryptoApi
+
 /**
  * BLAKE2b Keyed Hashing implementation
  *
@@ -65,10 +67,26 @@ public class BLAKE2b: BLAKE2Mac {
         key = key,
         bitStrength = bitStrength,
         personalization = personalization,
-        factory = org.kotlincrypto.hash.blake2.BLAKE2b,
+        factory = Companion,
     )
 
     private constructor(other: BLAKE2b): super(other)
 
     public override fun copy(): BLAKE2b = BLAKE2b(this)
+
+    private companion object: DigestFactory {
+
+        @OptIn(InternalKotlinCryptoApi::class)
+        override fun newInstance(
+            bitStrength: Int,
+            keyLength: Int,
+            salt: ByteArray?,
+            personalization: ByteArray?,
+        ): org.kotlincrypto.hash.blake2.BLAKE2b = org.kotlincrypto.hash.blake2.BLAKE2b(
+            bitStrength = bitStrength,
+            keyLength = keyLength,
+            salt = salt,
+            personalization = personalization,
+        )
+    }
 }
diff --git a/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2s.kt b/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2s.kt
index f93de19..fe5459d 100644
--- a/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2s.kt
+++ b/library/blake2/src/commonMain/kotlin/org/kotlincrypto/macs/blake2/BLAKE2s.kt
@@ -15,6 +15,8 @@
  **/
 package org.kotlincrypto.macs.blake2
 
+import org.kotlincrypto.core.InternalKotlinCryptoApi
+
 /**
  * BLAKE2s Keyed Hashing implementation
  *
@@ -65,10 +67,26 @@ public class BLAKE2s: BLAKE2Mac {
         key = key,
         bitStrength = bitStrength,
         personalization = personalization,
-        factory = org.kotlincrypto.hash.blake2.BLAKE2s,
+        factory = Companion,
     )
 
     private constructor(other: BLAKE2s): super(other)
 
     public override fun copy(): BLAKE2s = BLAKE2s(this)
+
+    private companion object: DigestFactory {
+
+        @OptIn(InternalKotlinCryptoApi::class)
+        override fun newInstance(
+            bitStrength: Int,
+            keyLength: Int,
+            salt: ByteArray?,
+            personalization: ByteArray?,
+        ): org.kotlincrypto.hash.blake2.BLAKE2s = org.kotlincrypto.hash.blake2.BLAKE2s(
+            bitStrength = bitStrength,
+            keyLength = keyLength,
+            salt = salt,
+            personalization = personalization,
+        )
+    }
 }