diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 241dc78..e3f6a18 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -1,6 +1,6 @@
 [versions]
-agp = "8.12.0"
-kotlin = "2.2.0"
+agp = "8.12.1"
+kotlin = "2.2.10"
 
 [libraries]
 junit = { module = "junit:junit", version = "4.13.2" }
diff --git a/library/build.gradle.kts b/library/build.gradle.kts
index 23ed558..1597fa6 100644
--- a/library/build.gradle.kts
+++ b/library/build.gradle.kts
@@ -12,7 +12,7 @@ android {
     compileSdk = 35
 
     defaultConfig {
-        minSdk = 24
+        minSdk = 26
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
 
diff --git a/library/src/main/cpp/CMakeLists.txt b/library/src/main/cpp/CMakeLists.txt
index 8256a10..21863b0 100644
--- a/library/src/main/cpp/CMakeLists.txt
+++ b/library/src/main/cpp/CMakeLists.txt
@@ -44,6 +44,7 @@ set(SOURCES
         ed25519.cpp
         curve25519.cpp
         hash.cpp
+        protocol.cpp
 )
 
 add_library( # Sets the name of the library.
diff --git a/library/src/main/cpp/group_keys.cpp b/library/src/main/cpp/group_keys.cpp
index 45f87f7..55f43bc 100644
--- a/library/src/main/cpp/group_keys.cpp
+++ b/library/src/main/cpp/group_keys.cpp
@@ -187,6 +187,13 @@ Java_network_loki_messenger_libsession_1util_GroupKeysConfig_keys(JNIEnv *env, j
     return jni_utils::jlist_from_collection(env, ptr->group_keys(), util::bytes_from_span);
 }
 
+extern "C"
+JNIEXPORT jobject JNICALL
+Java_network_loki_messenger_libsession_1util_GroupKeysConfig_groupEncKey(JNIEnv *env, jobject thiz) {
+    auto ptr = ptrToKeys(env, thiz);
+    return util::bytes_from_span(env, ptr->group_enc_key());
+}
+
 extern "C"
 JNIEXPORT jobject JNICALL
 Java_network_loki_messenger_libsession_1util_GroupKeysConfig_activeHashes(JNIEnv *env,
diff --git a/library/src/main/cpp/jni_utils.h b/library/src/main/cpp/jni_utils.h
index 5aca809..a9cc6f5 100644
--- a/library/src/main/cpp/jni_utils.h
+++ b/library/src/main/cpp/jni_utils.h
@@ -69,12 +69,18 @@ namespace jni_utils {
                 env_->DeleteLocalRef(ref_);
             }
         }
+        JavaLocalRef(JavaLocalRef&& other) : env_(other.env_), ref_(other.ref_) {
+            other.ref_ = nullptr;
+        }
+
+        JavaLocalRef(const JavaLocalRef&) = delete;
 
         inline JNIType get() const {
             return ref_;
         }
     };
 
+
     /**
      * Create a Java List from an iterator.
      *
@@ -162,6 +168,8 @@ namespace jni_utils {
                 data = std::span<char>(const_cast<char *>(c_str), env->GetStringUTFLength(s));
             }
 
+            JavaStringRef(const JavaStringRef &) = delete;
+
             ~JavaStringRef() {
                 env->ReleaseStringUTFChars(s, data.data());
             }
@@ -195,8 +203,18 @@ namespace jni_utils {
                 data = std::span<unsigned char>(reinterpret_cast<unsigned char *>(env->GetByteArrayElements(byte_array, nullptr)), length);
             }
 
+            JavaByteArrayRef(const JavaByteArrayRef &) = delete;
+
+            JavaByteArrayRef(JavaByteArrayRef&& other) : env(other.env), byte_array(other.byte_array), data(other.data) {
+                other.byte_array = nullptr;
+                other.data = {};
+            }
+
             ~JavaByteArrayRef() {
-                env->ReleaseByteArrayElements(byte_array, reinterpret_cast<jbyte *>(data.data()), 0);
+                if (byte_array) {
+                    env->ReleaseByteArrayElements(byte_array,
+                                                  reinterpret_cast<jbyte *>(data.data()), 0);
+                }
             }
 
             // Get the data as a span. Only valid during the lifetime of this object.
@@ -208,6 +226,24 @@ namespace jni_utils {
                 return std::vector(data.begin(), data.end());
             }
     };
+
+    template <size_t N>
+    static std::optional<std::array<unsigned char, N>> java_to_cpp_array(JNIEnv *env, jbyteArray array) {
+        if (!array) {
+            return std::nullopt;
+        }
+
+        JavaByteArrayRef bytes(env, array);
+        auto span = bytes.get();
+        if (span.size() != N) {
+            throw std::runtime_error("Invalid byte array length from java, expecting " + std::to_string(N) + " got " + std::to_string(span.size()));
+        }
+
+        std::array<unsigned char, N> out;
+        std::copy(span.begin(), span.end(), out.begin());
+        return out;
+    }
+
 }
 
 #endif //SESSION_ANDROID_JNI_UTILS_H
diff --git a/library/src/main/cpp/protocol.cpp b/library/src/main/cpp/protocol.cpp
new file mode 100644
index 0000000..68fb27c
--- /dev/null
+++ b/library/src/main/cpp/protocol.cpp
@@ -0,0 +1,189 @@
+#include <jni.h>
+#include <session/session_protocol.hpp>
+#include <session/sodium_array.hpp>
+
+#include "jni_utils.h"
+
+using namespace jni_utils;
+
+
+
+static JavaLocalRef<jobject> serializeProStatus(JNIEnv *env, const session::DecryptedEnvelope & envelope) {
+    if (!envelope.pro.has_value()) {
+        JavaLocalRef noneClass(env, env->FindClass("network/loki/messenger/libsession_util/protocol/ProStatus$None"));
+        auto fieldId = env->GetStaticFieldID(
+                noneClass.get(),
+                "INSTANCE", "Lnetwork/loki/messenger/libsession_util/protocol/ProStatus$None;");
+        return {env, env->GetStaticObjectField(noneClass.get(), fieldId)};
+    }
+
+    if (envelope.pro->status == session::config::ProStatus::Valid) {
+        JavaLocalRef validClass(env, env->FindClass("network/loki/messenger/libsession_util/protocol/ProStatus$Valid"));
+        auto init = env->GetMethodID(validClass.get(), "<init>", "(JJ)V");
+        return {env, env->NewObject(validClass.get(), init,
+                       static_cast<jlong>(envelope.pro->proof.expiry_unix_ts.time_since_epoch().count()),
+                       static_cast<jlong>(envelope.pro->features))};
+    }
+
+    JavaLocalRef invalidClass(env, env->FindClass("network/loki/messenger/libsession_util/protocol/ProStatus$Invalid"));
+    auto fieldId = env->GetStaticFieldID(
+            invalidClass.get(),
+            "INSTANCE", "Lnetwork/loki/messenger/libsession_util/protocol/ProStatus$Invalid;");
+    return {env, env->GetStaticObjectField(invalidClass.get(), fieldId)};
+}
+
+extern "C"
+JNIEXPORT jobject JNICALL
+Java_network_loki_messenger_libsession_1util_protocol_SessionProtocol_decryptEnvelope(JNIEnv *env,
+                                                                                      jobject thiz,
+                                                                                      jobject java_key,
+                                                                                      jbyteArray java_payload,
+                                                                                      jlong now_epoch_seconds,
+                                                                                      jbyteArray java_pro_backend_pub_key) {
+
+    session::DecryptEnvelopeKey key;
+
+    std::vector<std::span<const unsigned char>> privateKeysStorage;
+
+    struct RegularStorage {
+        JavaLocalRef<jbyteArray> ed25519PrivKeyRef;
+        JavaByteArrayRef ed25519PrivKeyBytesRef;
+    };
+
+    struct GroupData {
+        JavaLocalRef<jbyteArray> groupPubKeyRef;
+        JavaByteArrayRef groupPubKeyBytesRef;
+
+        std::vector<std::pair<JavaLocalRef<jbyteArray>, JavaByteArrayRef>> groupKeysRef;
+    };
+
+    std::optional<RegularStorage> regularStorage;
+    std::optional<GroupData> groupStorage;
+
+    JavaLocalRef regularClazz(env, env->FindClass("network/loki/messenger/libsession_util/protocol/DecryptEnvelopeKey$Regular"));
+    if (env->IsInstanceOf(java_key, regularClazz.get())) {
+        auto bytes = reinterpret_cast<jbyteArray>(env->CallObjectMethod(java_key, env->GetMethodID(regularClazz.get(), "getEd25519PrivKey", "()[B")));
+        regularStorage.emplace(RegularStorage {
+                .ed25519PrivKeyRef = JavaLocalRef(env, bytes),
+                .ed25519PrivKeyBytesRef = JavaByteArrayRef(env, bytes)
+        });
+
+        privateKeysStorage.push_back(regularStorage->ed25519PrivKeyBytesRef.get());
+    }
+
+    JavaLocalRef groupClazz(env, env->FindClass("network/loki/messenger/libsession_util/protocol/DecryptEnvelopeKey$Group"));
+    if (env->IsInstanceOf(java_key, groupClazz.get())) {
+        auto pubKeyBytes = reinterpret_cast<jbyteArray>(env->CallObjectMethod(java_key, env->GetMethodID(groupClazz.get(), "getGroupEd25519PubKey", "()[B")));
+        groupStorage.emplace(GroupData {
+                .groupPubKeyRef = JavaLocalRef(env, pubKeyBytes),
+                .groupPubKeyBytesRef = JavaByteArrayRef(env, pubKeyBytes)
+        });
+
+        key.group_ed25519_pubkey.emplace(groupStorage->groupPubKeyBytesRef.get());
+
+        JavaLocalRef privKeyArrays(env, reinterpret_cast<jobjectArray>(env->CallObjectMethod(java_key, env->GetMethodID(groupClazz.get(), "getGroupKeys", "()[[B"))));
+        for (int i = 0, size = env->GetArrayLength(privKeyArrays.get()); i < size; i++) {
+            auto bytes = reinterpret_cast<jbyteArray>(env->GetObjectArrayElement(privKeyArrays.get(), i));
+            const auto &last = groupStorage->groupKeysRef.emplace_back(JavaLocalRef(env, bytes), JavaByteArrayRef(env, bytes));
+            privateKeysStorage.emplace_back(last.second.get());
+        }
+    }
+
+    key.ed25519_privkeys = { privateKeysStorage.data(), privateKeysStorage.size() };
+
+    return run_catching_cxx_exception_or_throws<jobject>(env, [&] {
+        auto envelop = session::decrypt_envelope(key, JavaByteArrayRef(env, java_payload).get(),
+                                                 std::chrono::sys_seconds { std::chrono::seconds { now_epoch_seconds } },
+                                                 *java_to_cpp_array<32>(env, java_pro_backend_pub_key));
+
+        JavaLocalRef sender_ed25519(env, util::bytes_from_span(env, envelop.sender_ed25519_pubkey));
+        JavaLocalRef sender_x25519(env, util::bytes_from_span(env, envelop.sender_x25519_pubkey));
+        JavaLocalRef content(env, util::bytes_from_vector(env, envelop.content_plaintext));
+
+        JavaLocalRef envelopClass(env, env->FindClass("network/loki/messenger/libsession_util/protocol/DecryptedEnvelope"));
+        jmethodID init = env->GetMethodID(
+                envelopClass.get(),
+                "<init>",
+                "(Lnetwork/loki/messenger/libsession_util/protocol/ProStatus;[B[B[BJ)V"
+        );
+
+        return env->NewObject(envelopClass.get(), init,
+                              serializeProStatus(env, envelop).get(),
+                              content.get(),
+                              sender_ed25519.get(),
+                              sender_x25519.get(),
+                              static_cast<jlong>(envelop.envelope.timestamp.count()));
+    });
+}
+
+
+extern "C"
+JNIEXPORT jbyteArray JNICALL
+Java_network_loki_messenger_libsession_1util_protocol_SessionProtocol_encryptFor1o1(JNIEnv *env,
+                                                                                    jobject thiz,
+                                                                                    jbyteArray plaintext,
+                                                                                    jbyteArray my_ed25519_priv_key,
+                                                                                    jlong timestamp_ms,
+                                                                                    jbyteArray recipient_pub_key,
+                                                                                    jbyteArray pro_signature) {
+    return run_catching_cxx_exception_or_throws<jbyteArray>(env, [=] {
+        return util::bytes_from_vector(
+                env,
+                session::encrypt_for_1o1(
+                        JavaByteArrayRef(env, plaintext).get(),
+                        JavaByteArrayRef(env, my_ed25519_priv_key).get(),
+                        std::chrono::milliseconds { timestamp_ms },
+                        *java_to_cpp_array<33>(env, recipient_pub_key),
+                        java_to_cpp_array<64>(env, pro_signature)
+        ));
+    });
+}
+
+extern "C"
+JNIEXPORT jbyteArray JNICALL
+Java_network_loki_messenger_libsession_1util_protocol_SessionProtocol_encryptForCommunityInbox(
+        JNIEnv *env, jobject thiz, jbyteArray plaintext, jbyteArray my_ed25519_priv_key,
+        jlong timestamp_ms, jbyteArray recipient_pub_key, jbyteArray community_server_pub_key,
+        jbyteArray pro_signature) {
+    return run_catching_cxx_exception_or_throws<jbyteArray>(env, [=] {
+        return util::bytes_from_vector(
+                env,
+                session::encrypt_for_community_inbox(
+                        JavaByteArrayRef(env, plaintext).get(),
+                        JavaByteArrayRef(env, my_ed25519_priv_key).get(),
+                        std::chrono::milliseconds { timestamp_ms },
+                        *java_to_cpp_array<33>(env, recipient_pub_key),
+                        *java_to_cpp_array<32>(env, community_server_pub_key),
+                        java_to_cpp_array<64>(env, pro_signature)
+                ));
+    });
+}
+
+extern "C"
+JNIEXPORT jbyteArray JNICALL
+Java_network_loki_messenger_libsession_1util_protocol_SessionProtocol_encryptForGroup(JNIEnv *env,
+                                                                                      jobject thiz,
+                                                                                      jbyteArray plaintext,
+                                                                                      jbyteArray my_ed25519_priv_key,
+                                                                                      jlong timestamp_ms,
+                                                                                      jbyteArray group_ed25519_public_key,
+                                                                                      jbyteArray group_ed25519_private_key,
+                                                                                      jbyteArray pro_signature) {
+    return run_catching_cxx_exception_or_throws<jbyteArray>(env, [=] {
+        session::cleared_uc32 group_private_key;
+
+        auto array = *java_to_cpp_array<32>(env, group_ed25519_private_key);
+        std::copy(array.begin(), array.end(), group_private_key.begin());
+
+        return util::bytes_from_vector(
+                env,
+                session::encrypt_for_group(
+                        JavaByteArrayRef(env, plaintext).get(),
+                        JavaByteArrayRef(env, my_ed25519_priv_key).get(),
+                        std::chrono::milliseconds { timestamp_ms },
+                        *java_to_cpp_array<33>(env, group_ed25519_public_key),
+                        group_private_key,
+                        java_to_cpp_array<64>(env, pro_signature)
+                ));
+    });
+}
\ No newline at end of file
diff --git a/library/src/main/java/network/loki/messenger/libsession_util/Config.kt b/library/src/main/java/network/loki/messenger/libsession_util/Config.kt
index d177bf5..053ae71 100644
--- a/library/src/main/java/network/loki/messenger/libsession_util/Config.kt
+++ b/library/src/main/java/network/loki/messenger/libsession_util/Config.kt
@@ -221,6 +221,7 @@ sealed class ConfigSig(pointer: Long) : Config(pointer)
 
 interface ReadableGroupKeysConfig {
     fun groupKeys(): List<ByteArray>
+    fun groupEncKey(): ByteArray
     fun needsDump(): Boolean
     fun dump(): ByteArray
     fun needsRekey(): Boolean
diff --git a/library/src/main/java/network/loki/messenger/libsession_util/GroupKeysConfig.kt b/library/src/main/java/network/loki/messenger/libsession_util/GroupKeysConfig.kt
index 4f7fff9..2970257 100644
--- a/library/src/main/java/network/loki/messenger/libsession_util/GroupKeysConfig.kt
+++ b/library/src/main/java/network/loki/messenger/libsession_util/GroupKeysConfig.kt
@@ -39,6 +39,7 @@ class GroupKeysConfig private constructor(
     override fun namespace() = Namespace.GROUP_KEYS()
 
     external override fun groupKeys(): List<ByteArray>
+    external override fun groupEncKey(): ByteArray
     external override fun needsDump(): Boolean
     external override fun dump(): ByteArray
     external fun loadKey(message: ByteArray,
diff --git a/library/src/main/java/network/loki/messenger/libsession_util/protocol/DecryptEnvelopeKey.kt b/library/src/main/java/network/loki/messenger/libsession_util/protocol/DecryptEnvelopeKey.kt
new file mode 100644
index 0000000..58de8fd
--- /dev/null
+++ b/library/src/main/java/network/loki/messenger/libsession_util/protocol/DecryptEnvelopeKey.kt
@@ -0,0 +1,22 @@
+package network.loki.messenger.libsession_util.protocol
+
+
+sealed interface DecryptEnvelopeKey {
+
+    class Group(
+        val groupEd25519PubKey: ByteArray,
+        val groupKeys: Array<ByteArray>
+    ) : DecryptEnvelopeKey {
+        constructor(
+            groupEd25519PubKey: ByteArray,
+            groupKeys: Collection<ByteArray>
+        ) : this(
+            groupEd25519PubKey,
+            groupKeys.toTypedArray()
+        )
+    }
+
+    class Regular(
+        val ed25519PrivKey: ByteArray
+    ) : DecryptEnvelopeKey
+}
\ No newline at end of file
diff --git a/library/src/main/java/network/loki/messenger/libsession_util/protocol/DecryptedEnvelope.kt b/library/src/main/java/network/loki/messenger/libsession_util/protocol/DecryptedEnvelope.kt
new file mode 100644
index 0000000..637af9a
--- /dev/null
+++ b/library/src/main/java/network/loki/messenger/libsession_util/protocol/DecryptedEnvelope.kt
@@ -0,0 +1,26 @@
+package network.loki.messenger.libsession_util.protocol
+
+import network.loki.messenger.libsession_util.util.Bytes
+import java.time.Instant
+
+data class DecryptedEnvelope(
+    val proStatus: ProStatus,
+    val contentPlainText: Bytes,
+    val senderEd25519PubKey: Bytes,
+    val senderX25519PubKey: Bytes,
+    val timestamp: Instant
+) {
+    constructor(
+        proStatus: ProStatus,
+        contentPlainText: ByteArray,
+        senderEd25519PubKey: ByteArray,
+        senderX25519PubKey: ByteArray,
+        timestampEpochMills: Long
+    ): this(
+        proStatus = proStatus,
+        contentPlainText = Bytes(contentPlainText),
+        senderEd25519PubKey = Bytes(senderEd25519PubKey),
+        senderX25519PubKey = Bytes(senderX25519PubKey),
+        timestamp = Instant.ofEpochMilli(timestampEpochMills)
+    )
+}
diff --git a/library/src/main/java/network/loki/messenger/libsession_util/protocol/ProFeatures.kt b/library/src/main/java/network/loki/messenger/libsession_util/protocol/ProFeatures.kt
new file mode 100644
index 0000000..843be42
--- /dev/null
+++ b/library/src/main/java/network/loki/messenger/libsession_util/protocol/ProFeatures.kt
@@ -0,0 +1,24 @@
+package network.loki.messenger.libsession_util.protocol
+
+
+enum class ProFeature(internal val bitIndex: Int) {
+    HIGHER_CHARACTER_LIMIT(0),
+    PRO_BADGE(1),
+    ANIMATED_AVATAR(2),
+}
+
+internal fun Long.toFeatures(): Set<ProFeature> {
+    return buildSet(ProFeature.entries.size) {
+        for (entry in ProFeature.entries) {
+            if (this@toFeatures and (1L shl entry.bitIndex) != 0L) {
+                add(entry)
+            }
+        }
+    }
+}
+
+internal fun Collection<ProFeature>.toLong(): Long {
+    return fold(0L) { acc, entry ->
+        acc or (1L shl entry.bitIndex)
+    }
+}
\ No newline at end of file
diff --git a/library/src/main/java/network/loki/messenger/libsession_util/protocol/ProStatus.kt b/library/src/main/java/network/loki/messenger/libsession_util/protocol/ProStatus.kt
new file mode 100644
index 0000000..bf53bb8
--- /dev/null
+++ b/library/src/main/java/network/loki/messenger/libsession_util/protocol/ProStatus.kt
@@ -0,0 +1,22 @@
+package network.loki.messenger.libsession_util.protocol
+
+import java.time.Instant
+
+
+sealed interface ProStatus {
+    data object None : ProStatus
+    data object Invalid : ProStatus
+
+    data class Valid(
+        val expiresAt: Instant,
+        val proFeatures: Set<ProFeature>
+    ) {
+        constructor(
+            expiresAtEpochSeconds: Long,
+            proFeatures: Long
+        ): this(
+            expiresAt = Instant.ofEpochSecond(expiresAtEpochSeconds),
+            proFeatures = proFeatures.toFeatures()
+        )
+    }
+}
\ No newline at end of file
diff --git a/library/src/main/java/network/loki/messenger/libsession_util/protocol/SessionProtocol.kt b/library/src/main/java/network/loki/messenger/libsession_util/protocol/SessionProtocol.kt
new file mode 100644
index 0000000..8de9a48
--- /dev/null
+++ b/library/src/main/java/network/loki/messenger/libsession_util/protocol/SessionProtocol.kt
@@ -0,0 +1,38 @@
+package network.loki.messenger.libsession_util.protocol
+
+import network.loki.messenger.libsession_util.LibSessionUtilCApi
+
+object SessionProtocol : LibSessionUtilCApi() {
+    external fun encryptFor1o1(
+        plaintext: ByteArray,
+        myEd25519PrivKey: ByteArray,
+        timestampMs: Long,
+        recipientPubKey: ByteArray, // 33 bytes prefixed key
+        proSignature: ByteArray?, // 64 bytes
+    ): ByteArray
+
+    external fun encryptForCommunityInbox(
+        plaintext: ByteArray,
+        myEd25519PrivKey: ByteArray,
+        timestampMs: Long,
+        recipientPubKey: ByteArray, // 33 bytes prefixed key
+        communityServerPubKey: ByteArray, // 32 bytes key
+        proSignature: ByteArray?, // 64 bytes
+    ): ByteArray
+
+    external fun encryptForGroup(
+        plaintext: ByteArray,
+        myEd25519PrivKey: ByteArray,
+        timestampMs: Long,
+        groupEd25519PublicKey: ByteArray, // 33 bytes 03 prefixed key
+        groupEd25519PrivateKey: ByteArray, // 32 bytes group "encryption" key
+        proSignature: ByteArray?, // 64 bytes
+    ): ByteArray
+
+    external fun decryptEnvelope(
+        key: DecryptEnvelopeKey,
+        payload: ByteArray,
+        nowEpochSeconds: Long,
+        proBackendPubKey: ByteArray, // 32 bytes backend key
+    ): DecryptedEnvelope
+}
\ No newline at end of file
diff --git a/libsession-util b/libsession-util
index 3ee705f..e0ec4c1 160000
--- a/libsession-util
+++ b/libsession-util
@@ -1 +1 @@
-Subproject commit 3ee705f3248337c71c159a88f6baafe85c02f1c3
+Subproject commit e0ec4c198ba003acf95f96e29e2e855b8ae3fad5