diff --git a/pgpainless-core/src/main/java/org/pgpainless/signature/builder/DirectKeySignatureBuilder.java b/pgpainless-core/src/main/java/org/pgpainless/signature/builder/DirectKeySignatureBuilder.java
index f65c7bb8..6871bea6 100644
--- a/pgpainless-core/src/main/java/org/pgpainless/signature/builder/DirectKeySignatureBuilder.java
+++ b/pgpainless-core/src/main/java/org/pgpainless/signature/builder/DirectKeySignatureBuilder.java
@@ -21,8 +21,8 @@ public class DirectKeySignatureBuilder extends AbstractSignatureBuilder<DirectKe
         super(certificationKey, protector, archetypeSignature);
     }
 
-    public DirectKeySignatureBuilder(SignatureType signatureType, PGPSecretKey signingKey, SecretKeyRingProtector protector) throws WrongPassphraseException {
-        super(signatureType, signingKey, protector);
+    public DirectKeySignatureBuilder(PGPSecretKey signingKey, SecretKeyRingProtector protector) throws WrongPassphraseException {
+        super(SignatureType.DIRECT_KEY, signingKey, protector);
     }
 
     public SelfSignatureSubpackets getHashedSubpackets() {
diff --git a/pgpainless-core/src/test/java/org/pgpainless/signature/builder/DirectKeySignatureBuilderTest.java b/pgpainless-core/src/test/java/org/pgpainless/signature/builder/DirectKeySignatureBuilderTest.java
new file mode 100644
index 00000000..0ab09eb0
--- /dev/null
+++ b/pgpainless-core/src/test/java/org/pgpainless/signature/builder/DirectKeySignatureBuilderTest.java
@@ -0,0 +1,74 @@
+// SPDX-FileCopyrightText: 2021 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package org.pgpainless.signature.builder;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+import java.security.InvalidAlgorithmParameterException;
+import java.security.NoSuchAlgorithmException;
+import java.util.Collections;
+
+import org.bouncycastle.openpgp.PGPException;
+import org.bouncycastle.openpgp.PGPSecretKeyRing;
+import org.bouncycastle.openpgp.PGPSignature;
+import org.junit.jupiter.api.Test;
+import org.pgpainless.PGPainless;
+import org.pgpainless.algorithm.CompressionAlgorithm;
+import org.pgpainless.algorithm.Feature;
+import org.pgpainless.algorithm.HashAlgorithm;
+import org.pgpainless.algorithm.KeyFlag;
+import org.pgpainless.algorithm.SignatureType;
+import org.pgpainless.algorithm.SymmetricKeyAlgorithm;
+import org.pgpainless.key.info.KeyRingInfo;
+import org.pgpainless.key.protection.SecretKeyRingProtector;
+import org.pgpainless.key.util.KeyRingUtils;
+import org.pgpainless.signature.subpackets.SelfSignatureSubpackets;
+import org.pgpainless.signature.subpackets.SignatureSubpacketsUtil;
+
+public class DirectKeySignatureBuilderTest {
+
+    @Test
+    public void testDirectKeySignatureBuilding() throws PGPException, InvalidAlgorithmParameterException, NoSuchAlgorithmException, InterruptedException {
+        PGPSecretKeyRing secretKeys = PGPainless.generateKeyRing()
+                .modernKeyRing("Alice", null);
+
+        DirectKeySignatureBuilder dsb = new DirectKeySignatureBuilder(
+                secretKeys.getSecretKey(),
+                SecretKeyRingProtector.unprotectedKeys());
+
+        dsb.applyCallback(new SelfSignatureSubpackets.Callback() {
+            @Override
+            public void modifyHashedSubpackets(SelfSignatureSubpackets hashedSubpackets) {
+                hashedSubpackets.setKeyFlags(KeyFlag.CERTIFY_OTHER);
+                hashedSubpackets.setPreferredHashAlgorithms(HashAlgorithm.SHA512);
+                hashedSubpackets.setPreferredCompressionAlgorithms(CompressionAlgorithm.ZIP);
+                hashedSubpackets.setPreferredSymmetricKeyAlgorithms(SymmetricKeyAlgorithm.AES_256);
+                hashedSubpackets.setFeatures(Feature.MODIFICATION_DETECTION);
+            }
+        });
+
+        Thread.sleep(1000);
+
+        PGPSignature directKeySig = dsb.build(secretKeys.getPublicKey());
+        assertNotNull(directKeySig);
+        secretKeys = KeyRingUtils.injectCertification(secretKeys, secretKeys.getPublicKey(), directKeySig);
+
+        KeyRingInfo info = PGPainless.inspectKeyRing(secretKeys);
+        PGPSignature signature = info.getLatestDirectKeySelfSignature();
+
+        assertNotNull(signature);
+        assertEquals(directKeySig, signature);
+
+        assertEquals(SignatureType.DIRECT_KEY, SignatureType.valueOf(signature.getSignatureType()));
+        assertEquals(Collections.singletonList(KeyFlag.CERTIFY_OTHER), SignatureSubpacketsUtil.parseKeyFlags(signature));
+        assertEquals(Collections.singleton(HashAlgorithm.SHA512), SignatureSubpacketsUtil.parsePreferredHashAlgorithms(signature));
+        assertEquals(Collections.singleton(CompressionAlgorithm.ZIP), SignatureSubpacketsUtil.parsePreferredCompressionAlgorithms(signature));
+        assertEquals(Collections.singleton(SymmetricKeyAlgorithm.AES_256), SignatureSubpacketsUtil.parsePreferredSymmetricKeyAlgorithms(signature));
+        assertEquals(secretKeys.getPublicKey().getKeyID(), signature.getKeyID());
+        assertArrayEquals(secretKeys.getPublicKey().getFingerprint(), signature.getHashedSubPackets().getIssuerFingerprint().getFingerprint());
+    }
+}