diff --git a/pgpainless-core/src/main/java/org/pgpainless/authentication/CertificateAuthenticity.java b/pgpainless-core/src/main/java/org/pgpainless/authentication/CertificateAuthenticity.java
deleted file mode 100644
index ac059646..00000000
--- a/pgpainless-core/src/main/java/org/pgpainless/authentication/CertificateAuthenticity.java
+++ /dev/null
@@ -1,139 +0,0 @@
-// SPDX-FileCopyrightText: 2023 Paul Schaub <vanitasvitae@fsfe.org>
-//
-// SPDX-License-Identifier: Apache-2.0
-
-package org.pgpainless.authentication;
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import javax.annotation.Nonnull;
-
-import org.bouncycastle.openpgp.PGPPublicKeyRing;
-
-public class CertificateAuthenticity {
-
-    private final String userId;
-    private final PGPPublicKeyRing certificate;
-    private final Map<CertificationChain, Integer> certificationChains = new HashMap<>();
-    private final int targetAmount;
-
-    public CertificateAuthenticity(@Nonnull PGPPublicKeyRing certificate,
-                                   @Nonnull String userId,
-                                   @Nonnull Map<CertificationChain, Integer> certificationChains,
-                                   int targetAmount) {
-        this.userId = userId;
-        this.certificate = certificate;
-        this.certificationChains.putAll(certificationChains);
-        this.targetAmount = targetAmount;
-    }
-
-    @Nonnull
-    public String getUserId() {
-        return userId;
-    }
-
-    @Nonnull
-    public PGPPublicKeyRing getCertificate() {
-        return certificate;
-    }
-
-    public int getTotalTrustAmount() {
-        int total = 0;
-        for (int v : certificationChains.values()) {
-            total += v;
-        }
-        return total;
-    }
-
-    /**
-     * Return the degree of authentication of the binding in percent.
-     * 100% means full authentication.
-     * Values smaller than 100% mean partial authentication.
-     *
-     * @return authenticity in percent
-     */
-    public int getAuthenticityPercentage() {
-        return targetAmount * 100 / getTotalTrustAmount();
-    }
-
-    /**
-     * Return true, if the binding is authenticated to a sufficient degree.
-     *
-     * @return true if total gathered evidence outweighs the target trust amount.
-     */
-    public boolean isAuthenticated() {
-        return targetAmount <= getTotalTrustAmount();
-    }
-
-    /**
-     * Return a map of {@link CertificationChain CertificationChains} and their respective effective trust amount.
-     * The effective trust amount of a path might be smaller than its actual trust amount, for example if nodes of a
-     * path are used multiple times.
-     *
-     * @return map of certification chains and their effective trust amounts
-     */
-    @Nonnull
-    public Map<CertificationChain, Integer> getCertificationChains() {
-        return Collections.unmodifiableMap(certificationChains);
-    }
-
-    public static class CertificationChain {
-        private final int trustAmount;
-        private final List<ChainLink> chainLinks = new ArrayList<>();
-
-        /**
-         * A chain of certifications.
-         *
-         * @param trustAmount actual trust amount of the chain
-         * @param chainLinks links of the chain, starting at the trust-root, ending at the target.
-         */
-        public CertificationChain(int trustAmount, @Nonnull List<ChainLink> chainLinks) {
-            this.trustAmount = trustAmount;
-            this.chainLinks.addAll(chainLinks);
-        }
-
-        /**
-         * Actual trust amount of the certification chain.
-         * @return trust amount
-         */
-        public int getTrustAmount() {
-            return trustAmount;
-        }
-
-        /**
-         * Return all links in the chain, starting at the trust-root and ending at the target.
-         * @return chain links
-         */
-        @Nonnull
-        public List<ChainLink> getChainLinks() {
-            return Collections.unmodifiableList(chainLinks);
-        }
-    }
-
-    /**
-     * A chain link contains a node in the trust chain.
-     */
-    public static class ChainLink {
-        private final PGPPublicKeyRing certificate;
-
-        /**
-         * Create a chain link.
-         * @param certificate node in the trust chain
-         */
-        public ChainLink(@Nonnull PGPPublicKeyRing certificate) {
-            this.certificate = certificate;
-        }
-
-        /**
-         * Return the certificate that belongs to the node.
-         * @return certificate
-         */
-        @Nonnull
-        public PGPPublicKeyRing getCertificate() {
-            return certificate;
-        }
-    }
-}
diff --git a/pgpainless-core/src/main/java/org/pgpainless/authentication/CertificateAuthenticity.kt b/pgpainless-core/src/main/java/org/pgpainless/authentication/CertificateAuthenticity.kt
new file mode 100644
index 00000000..2024c710
--- /dev/null
+++ b/pgpainless-core/src/main/java/org/pgpainless/authentication/CertificateAuthenticity.kt
@@ -0,0 +1,57 @@
+// SPDX-FileCopyrightText: 2023 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package org.pgpainless.authentication
+
+import org.bouncycastle.openpgp.PGPPublicKeyRing
+
+class CertificateAuthenticity(val userId: String,
+                              val certificate: PGPPublicKeyRing,
+                              val certificationChains: Map<CertificationChain, Int>,
+                              val targetAmount: Int) {
+
+    val totalTrustAmount: Int
+        get() = certificationChains.values.sum()
+
+
+    /**
+     * Return the degree of authentication of the binding in percent.
+     * 100% means full authentication.
+     * Values smaller than 100% mean partial authentication.
+     *
+     * @return authenticity in percent
+     */
+    val authenticityPercentage: Int
+        get() = targetAmount * 100 / totalTrustAmount
+
+    /**
+     * Return true, if the binding is authenticated to a sufficient degree.
+     *
+     * @return true if total gathered evidence outweighs the target trust amount.
+     */
+    val authenticated: Boolean
+        get() = targetAmount <= totalTrustAmount
+
+    fun isAuthenticated() = authenticated
+}
+
+/**
+ * A chain of certifications.
+ *
+ * @param trustAmount actual trust amount of the chain
+ * @param chainLinks links of the chain, starting at the trust-root, ending at the target.
+ */
+class CertificationChain(
+        val trustAmount: Int,
+        val chainLinks: List<ChainLink>) {
+
+}
+
+/**
+ * A chain link contains a node in the trust chain.
+ */
+class ChainLink(
+        val certificate: PGPPublicKeyRing) {
+
+}
\ No newline at end of file