diff --git a/pgpainless-core/src/main/java/org/pgpainless/key/generation/KeySpec.java b/pgpainless-core/src/main/java/org/pgpainless/key/generation/KeySpec.java
deleted file mode 100644
index 6ac08aa7..00000000
--- a/pgpainless-core/src/main/java/org/pgpainless/key/generation/KeySpec.java
+++ /dev/null
@@ -1,62 +0,0 @@
-// SPDX-FileCopyrightText: 2018 Paul Schaub <vanitasvitae@fsfe.org>
-//
-// SPDX-License-Identifier: Apache-2.0
-
-package org.pgpainless.key.generation;
-
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-
-import org.bouncycastle.openpgp.PGPSignatureSubpacketVector;
-import org.pgpainless.algorithm.KeyFlag;
-import org.pgpainless.key.generation.type.KeyType;
-import org.pgpainless.signature.subpackets.SignatureSubpackets;
-import org.pgpainless.signature.subpackets.SignatureSubpacketsHelper;
-
-import java.util.Date;
-
-public class KeySpec {
-
-    private final KeyType keyType;
-    private final SignatureSubpackets subpacketGenerator;
-    private final boolean inheritedSubPackets;
-    private final Date keyCreationDate;
-
-    KeySpec(@Nonnull KeyType type,
-            @Nonnull SignatureSubpackets subpacketGenerator,
-            boolean inheritedSubPackets,
-            @Nullable Date keyCreationDate) {
-        this.keyType = type;
-        this.subpacketGenerator = subpacketGenerator;
-        this.inheritedSubPackets = inheritedSubPackets;
-        this.keyCreationDate = keyCreationDate;
-    }
-
-    @Nonnull
-    public KeyType getKeyType() {
-        return keyType;
-    }
-
-    @Nonnull
-    public PGPSignatureSubpacketVector getSubpackets() {
-        return SignatureSubpacketsHelper.toVector(subpacketGenerator);
-    }
-
-    @Nonnull
-    public SignatureSubpackets getSubpacketGenerator() {
-        return subpacketGenerator;
-    }
-
-    boolean isInheritedSubPackets() {
-        return inheritedSubPackets;
-    }
-
-    @Nullable
-    public Date getKeyCreationDate() {
-        return keyCreationDate;
-    }
-
-    public static KeySpecBuilder getBuilder(KeyType type, KeyFlag... flags) {
-        return new KeySpecBuilder(type, flags);
-    }
-}
diff --git a/pgpainless-core/src/main/kotlin/org/pgpainless/key/generation/KeySpec.kt b/pgpainless-core/src/main/kotlin/org/pgpainless/key/generation/KeySpec.kt
new file mode 100644
index 00000000..fd0b8635
--- /dev/null
+++ b/pgpainless-core/src/main/kotlin/org/pgpainless/key/generation/KeySpec.kt
@@ -0,0 +1,28 @@
+// SPDX-FileCopyrightText: 2023 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package org.pgpainless.key.generation
+
+import org.bouncycastle.openpgp.PGPSignatureSubpacketVector
+import org.pgpainless.algorithm.KeyFlag
+import org.pgpainless.key.generation.type.KeyType
+import org.pgpainless.signature.subpackets.SignatureSubpackets
+import org.pgpainless.signature.subpackets.SignatureSubpacketsHelper
+import java.util.*
+
+data class KeySpec(
+        val keyType: KeyType,
+        val subpacketGenerator: SignatureSubpackets,
+        val isInheritedSubPackets: Boolean,
+        val keyCreationDate: Date
+) {
+
+    val subpackets: PGPSignatureSubpacketVector
+        get() = SignatureSubpacketsHelper.toVector(subpacketGenerator)
+
+    companion object {
+        @JvmStatic
+        fun getBuilder(type: KeyType, vararg flags: KeyFlag) = KeySpecBuilder(type, *flags)
+    }
+}
\ No newline at end of file