diff --git a/tests/test_olm_using_malloc.cpp b/tests/test_olm_using_malloc.cpp
new file mode 100644
index 0000000..84fbbd7
--- /dev/null
+++ b/tests/test_olm_using_malloc.cpp
@@ -0,0 +1,210 @@
+#include "olm/olm.hh"
+#include "unittest.hh"
+
+#include <cstddef>
+#include <cstdint>
+#include <cstring>
+
+struct MockRandom {
+    MockRandom(std::uint8_t tag, std::uint8_t offset = 0)
+        : tag(tag), current(offset) {}
+    void operator()(
+        void * buf, std::size_t length
+    ) {
+        std::uint8_t * bytes = (std::uint8_t *) buf;
+        while (length > 32) {
+            bytes[0] = tag;
+            std::memset(bytes + 1, current, 31);
+            length -= 32;
+            bytes += 32;
+            current += 1;
+        }
+        if (length) {
+            bytes[0] = tag;
+            std::memset(bytes + 1, current, length - 1);
+            current += 1;
+        }
+    }
+    std::uint8_t tag;
+    std::uint8_t current;
+};
+
+std::uint8_t * check_malloc(std::size_t size) {
+    if (size == std::size_t(-1)) {
+        assert_not_equals(std::size_t(-1), size);
+    }
+    return (std::uint8_t *)::malloc(size);
+}
+
+int main() {
+
+{ /** More messages test */
+
+TestCase test_case("More messages test");
+MockRandom mock_random_a('A', 0x00);
+MockRandom mock_random_b('B', 0x80);
+
+void * a_account_buffer = check_malloc(::olm_account_size());
+::OlmAccount *a_account = ::olm_account(a_account_buffer);
+
+std::size_t a_random_size = ::olm_create_account_random_length(a_account);
+void * a_random = check_malloc(a_random_size);
+mock_random_a(a_random, a_random_size);
+::olm_create_account(a_account, a_random, a_random_size);
+free(a_random);
+
+void * b_account_buffer = check_malloc(::olm_account_size());
+::OlmAccount *b_account = ::olm_account(b_account_buffer);
+
+std::size_t b_random_size = ::olm_create_account_random_length(b_account);
+void * b_random = check_malloc(b_random_size);
+mock_random_b(b_random, b_random_size);
+::olm_create_account(b_account, b_random, b_random_size);
+free(b_random);
+
+std::size_t o_random_size = ::olm_account_generate_one_time_keys_random_length(
+    b_account, 42
+);
+void * o_random = check_malloc(o_random_size);
+mock_random_b(o_random, o_random_size);
+::olm_account_generate_one_time_keys(b_account, 42, o_random, o_random_size);
+free(o_random);
+
+
+std::size_t b_id_keys_size = ::olm_account_identity_keys_length(b_account);
+std::size_t b_ot_keys_size = ::olm_account_one_time_keys_length(b_account);
+std::uint8_t * b_id_keys = (std::uint8_t *) check_malloc(b_id_keys_size);
+std::uint8_t * b_ot_keys = (std::uint8_t *) check_malloc(b_ot_keys_size);
+::olm_account_identity_keys(b_account, b_id_keys, b_id_keys_size);
+::olm_account_one_time_keys(b_account, b_ot_keys, b_ot_keys_size);
+
+void * a_session_buffer = check_malloc(::olm_session_size());
+::OlmSession *a_session = ::olm_session(a_session_buffer);
+
+std::size_t a_rand_size = ::olm_create_outbound_session_random_length(a_session);
+void * a_rand = check_malloc(a_rand_size);
+mock_random_a(a_rand, a_rand_size);
+assert_not_equals(std::size_t(-1), ::olm_create_outbound_session(
+    a_session, a_account,
+    b_id_keys + 15, 43,
+    b_ot_keys + 25, 43,
+    a_rand, a_rand_size
+));
+free(b_id_keys);
+free(b_ot_keys);
+free(a_rand);
+
+void * plaintext = malloc(12);
+::memcpy(plaintext, "Hello, World", 12);
+
+std::size_t message_1_size = ::olm_encrypt_message_length(a_session, 12);
+void * message_1 = check_malloc(message_1_size);
+std::size_t a_message_random_size = ::olm_encrypt_random_length(a_session);
+void * a_message_random = check_malloc(a_message_random_size);
+mock_random_a(a_message_random, a_message_random_size);
+assert_equals(std::size_t(0), ::olm_encrypt_message_type(a_session));
+assert_not_equals(std::size_t(-1), ::olm_encrypt(
+    a_session,
+    plaintext, 12,
+    a_message_random, a_message_random_size,
+    message_1, message_1_size
+));
+free(a_message_random);
+
+void * tmp_message_1 = check_malloc(message_1_size);
+std::memcpy(tmp_message_1, message_1, message_1_size);
+
+void * b_session_buffer = check_malloc(olm_account_size());
+::OlmSession *b_session = ::olm_session(b_session_buffer);
+::olm_create_inbound_session(
+    b_session, b_account, tmp_message_1, message_1_size
+);
+
+std::memcpy(tmp_message_1, message_1, message_1_size);
+
+std::size_t plaintext_1_size = ::olm_decrypt_max_plaintext_length(
+    b_session, 0, tmp_message_1, message_1_size
+);
+void * plaintext_1 = check_malloc(plaintext_1_size);
+std::memcpy(tmp_message_1, message_1, message_1_size);
+assert_equals(std::size_t(12), ::olm_decrypt(
+    b_session, 0,
+    tmp_message_1, message_1_size,
+    plaintext_1, plaintext_1_size
+));
+free(tmp_message_1);
+free(plaintext_1);
+free(message_1);
+
+assert_not_equals(
+    std::size_t(-1), ::olm_remove_one_time_keys(b_account, b_session)
+);
+
+for (unsigned i = 0; i < 8; ++i) {
+    {
+    std::size_t msg_a_size = ::olm_encrypt_message_length(a_session, 12);
+    std::size_t rnd_a_size = ::olm_encrypt_random_length(a_session);
+    void * msg_a = check_malloc(msg_a_size);
+    void * rnd_a = check_malloc(rnd_a_size);
+    mock_random_a(rnd_a, rnd_a_size);
+    std::size_t type_a = ::olm_encrypt_message_type(a_session);
+    assert_not_equals(std::size_t(-1), ::olm_encrypt(
+        a_session, plaintext, 12, rnd_a, rnd_a_size, msg_a, msg_a_size
+    ));
+    free(rnd_a);
+
+    void * tmp_a = check_malloc(msg_a_size);
+    std::memcpy(tmp_a, msg_a, msg_a_size);
+    std::size_t out_a_size = ::olm_decrypt_max_plaintext_length(
+        b_session, type_a, tmp_a, msg_a_size
+    );
+    void * out_a = check_malloc(out_a_size);
+    std::memcpy(tmp_a, msg_a, msg_a_size);
+    assert_equals(std::size_t(12), ::olm_decrypt(
+        b_session, type_a, tmp_a, msg_a_size, out_a, out_a_size
+    ));
+    free(tmp_a);
+    free(msg_a);
+    free(out_a);
+    }
+    {
+    std::size_t msg_b_size = ::olm_encrypt_message_length(b_session, 12);
+    std::size_t rnd_b_size = ::olm_encrypt_random_length(b_session);
+    void * msg_b = check_malloc(msg_b_size);
+    void * rnd_b = check_malloc(rnd_b_size);
+    mock_random_b(rnd_b, rnd_b_size);
+    std::size_t type_b = ::olm_encrypt_message_type(b_session);
+    assert_not_equals(std::size_t(-1), ::olm_encrypt(
+            b_session, plaintext, 12, rnd_b, rnd_b_size, msg_b, msg_b_size
+    ));
+    free(rnd_b);
+
+    void * tmp_b = check_malloc(msg_b_size);
+    std::memcpy(tmp_b, msg_b, msg_b_size);
+    std::size_t out_b_size = ::olm_decrypt_max_plaintext_length(
+            a_session, type_b, tmp_b, msg_b_size
+    );
+    void * out_b = check_malloc(out_b_size);
+    std::memcpy(tmp_b, msg_b, msg_b_size);
+    assert_equals(std::size_t(12), ::olm_decrypt(
+            a_session, type_b, msg_b, msg_b_size, out_b, out_b_size
+    ));
+    free(tmp_b);
+    free(msg_b);
+    free(out_b);
+    }
+}
+::olm_clear_account(a_account);
+::olm_clear_account(b_account);
+::olm_clear_session(a_session);
+::olm_clear_session(b_session);
+
+free(a_account_buffer);
+free(b_account_buffer);
+free(a_session_buffer);
+free(b_session_buffer);
+free(plaintext);
+
+}
+
+}