diff --git a/.docker/Dockerfile b/.docker/Dockerfile
index 47cacfaf867e18c7ecfa8629e0d31cc00d5edf9c..a0d975f82b721dd71cc1e4f7e724c47c20e28a55 100644
--- a/.docker/Dockerfile
+++ b/.docker/Dockerfile
@@ -13,6 +13,8 @@ COPY . /caosdb-cppinttest
 WORKDIR /caosdb-cppinttest
 RUN rm -rf .git
 
+COPY .docker/caosdb-client.json /caosdb-client.json
+
 # build and run tests
 CMD mkdir build && \
     cd build && \
diff --git a/.docker/caosdb-client.json b/.docker/caosdb-client.json
new file mode 100644
index 0000000000000000000000000000000000000000..5da162e2561da384892fc62e02f2fdaddad2e6aa
--- /dev/null
+++ b/.docker/caosdb-client.json
@@ -0,0 +1,14 @@
+{
+  "connections": {
+    "default": {
+      "host": "caosdb-server",
+      "port": 8443,
+      "server_certificate_path": "/cert/caosdb.cert.pem",
+      "authentication": {
+        "type": "plain",
+        "username": "admin",
+        "password": "caosdb"
+      }
+    }
+  }
+}
diff --git a/.docker/tester.yml b/.docker/tester.yml
index f801f421f2cfb179da86f69cd5bc58d312f48882..764fcd63475a8baa1b2e8aed533336f1326c161f 100644
--- a/.docker/tester.yml
+++ b/.docker/tester.yml
@@ -5,6 +5,7 @@ services:
     environment:
       CAOSDB_SERVER_HOST: caosdb-server
       CAOSDB_SERVER_CERT: /cert/caosdb.cert.pem
+      CAOSDB_CLIENT_CONFIGURATION: /caosdb-client.json
     networks:
       - docker_caosnet
     volumes:
diff --git a/conanfile.txt b/conanfile.txt
index 6e14d4783d406fd06def9dcd692db8622712f9d3..048f038956408610ddfa02e4d3b780b990f2d657 100644
--- a/conanfile.txt
+++ b/conanfile.txt
@@ -1,5 +1,5 @@
 [requires]
-caosdb/0.0.4
+caosdb/0.0.5
 gtest/1.11.0
 
 [generators]
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 81f1fbe0be5d70c05c6b395ab56f38c922dae004..49dde42cf0d3a578f9bd1f50cd99b1c88ccf3fcb 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -24,6 +24,7 @@
 set(test_cases
     test_connection
     test_transaction
+    test_ccaosdb
     )
 
 #######################################################
diff --git a/test/test_ccaosdb.cpp b/test/test_ccaosdb.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..3b99e8e0c8869230648b5d85359e3ecbeebf07e6
--- /dev/null
+++ b/test/test_ccaosdb.cpp
@@ -0,0 +1,42 @@
+/*
+ * This file is a part of the CaosDB Project.
+ *
+ * Copyright (C) 2021 Timm Fitschen <t.fitschen@indiscale.com>
+ * Copyright (C) 2021 IndiScale GmbH <info@indiscale.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+#include <memory>                  // for allocator, unique_ptr
+#include "ccaosdb.h"               // for caosdb_info_version_info, caosdb_...
+#include "gtest/gtest-message.h"   // for Message
+#include "gtest/gtest-test-part.h" // for TestPartResult
+#include "gtest/gtest_pred_impl.h" // for Test, EXPECT_EQ, SuiteApiResolver
+
+TEST(test_ccaosdb, connection_ssl_authentication_success) {
+
+  caosdb_connection_connection connection;
+  caosdb_connection_connection_manager_get_default_connection(&connection);
+
+  caosdb_info_version_info version_info;
+  caosdb_connection_get_version_info(&version_info, &connection);
+
+  auto major = caosdb_constants_COMPATIBLE_SERVER_VERSION_MAJOR();
+  auto minor = caosdb_constants_COMPATIBLE_SERVER_VERSION_MINOR();
+  const auto *const pre_release =
+    caosdb_constants_COMPATIBLE_SERVER_VERSION_PRE_RELEASE();
+
+  EXPECT_EQ(major, version_info.major);
+  EXPECT_EQ(minor, version_info.minor);
+  EXPECT_STREQ(pre_release, version_info.pre_release);
+}
diff --git a/test/test_connection.cpp b/test/test_connection.cpp
index fddc26b97e23f3fbd1c658ee6a93899c93f1ebe5..08eec662fd93ac3e0b7b05579f0aa4c184017a38 100644
--- a/test/test_connection.cpp
+++ b/test/test_connection.cpp
@@ -23,13 +23,13 @@
 #include <memory>                  // for make_shared, allocator, shared_ptr
 #include <string>                  // for string
 #include "caosdb/authentication.h" // for PlainPasswordAuthenticator
-#include "caosdb/connection.h"     // for InsecureCaosDBConnectionConfig
+#include "caosdb/connection.h"     // for InsecureConnectionConfiguration
 #include "caosdb/exceptions.h"     // for AuthenticationError, ConnectionError
 #include "caosdb/info.h"           // for VersionInfo
-#include "caosdb/utils.h"          // for get_env_var
+#include "caosdb/utility.h"        // for get_env_var
 #include "gtest/gtest_pred_impl.h" // for Test, TEST, EXPECT_EQ, EXPECT_THROW
 #include "caosdb_test_utility.h"
-#include "test_connection.h"
+#include "caosdb/constants.h"
 
 namespace caosdb::connection {
 using caosdb::authentication::PlainPasswordAuthenticator;
@@ -38,82 +38,81 @@ using caosdb::exceptions::ConnectionError;
 
 TEST(test_connection, config_somehost_25323) {
   auto port = 25323;
-  const auto *pHost = "somehost";
-  auto config = std::make_unique<InsecureCaosDBConnectionConfig>(pHost, port);
+  const auto *host = "somehost";
+  auto config = InsecureConnectionConfiguration(host, port);
 
-  EXPECT_EQ(pHost, config->getHost());
-  EXPECT_EQ(port, config->getPort());
+  EXPECT_EQ(host, config.GetHost());
+  EXPECT_EQ(port, config.GetPort());
 }
 
 TEST(test_connection, connect_somehost_42347_fails) {
   auto port = 42347;
-  const auto *pHost = "somehost";
-  auto config = std::make_shared<InsecureCaosDBConnectionConfig>(pHost, port);
-  CaosDBConnection connection(config);
+  const auto *host = "somehost";
+  auto config = InsecureConnectionConfiguration(host, port);
+  Connection connection(config);
 
   EXPECT_THROW(connection.GetVersionInfo(), ConnectionError);
 }
 
 TEST(test_connection, connection_insecure_authentication_error_anonymous) {
-  auto port_str =
-    caosdb::utils::get_env_var("CAOSDB_SERVER_GRPC_PORT_HTTP", "8080");
+  const auto *port_str =
+    caosdb::utility::get_env_var("CAOSDB_SERVER_GRPC_PORT_HTTP", "8080");
   auto port = std::stoi(port_str);
-  const auto host =
-    caosdb::utils::get_env_var("CAOSDB_SERVER_HOST", "localhost");
+  const auto *const host =
+    caosdb::utility::get_env_var("CAOSDB_SERVER_HOST", "localhost");
 
-  auto config = std::make_shared<InsecureCaosDBConnectionConfig>(host, port);
-  auto connection = CaosDBConnection(config);
+  auto config = InsecureConnectionConfiguration(host, port);
+  auto connection = Connection(config);
 
   EXPECT_THROW(connection.GetVersionInfo(), AuthenticationError);
 }
 
 TEST(test_connection, connection_ssl_authentication_error_anonymous) {
-  auto port_str =
-    caosdb::utils::get_env_var("CAOSDB_SERVER_GRPC_PORT_HTTPS", "8443");
+  const auto *port_str =
+    caosdb::utility::get_env_var("CAOSDB_SERVER_GRPC_PORT_HTTPS", "8443");
   auto port = std::stoi(port_str);
-  const auto host =
-    caosdb::utils::get_env_var("CAOSDB_SERVER_HOST", "localhost");
+  const auto *const host =
+    caosdb::utility::get_env_var("CAOSDB_SERVER_HOST", "localhost");
   const auto path =
-    caosdb::utils::get_env_var("CAOSDB_SERVER_CERT", std::string());
+    caosdb::utility::get_env_var("CAOSDB_SERVER_CERT", std::string());
 
-  auto ssloptions = std::make_shared<PemFileCACertProvider>(path);
-  auto config =
-    std::make_shared<SslCaosDBConnectionConfig>(host, port, ssloptions);
-  auto connection = CaosDBConnection(config);
+  auto cert = PemFileCertificateProvider(path);
+  auto config = TlsConnectionConfiguration(host, port, cert);
+  auto connection = Connection(config);
 
   EXPECT_THROW_MESSAGE(connection.GetVersionInfo(), AuthenticationError,
                        "Please login.");
 }
 
 TEST(test_connection, connection_ssl_authentication_error_wrong_credentials) {
-  auto port_str =
-    caosdb::utils::get_env_var("CAOSDB_SERVER_GRPC_PORT_HTTPS", "8443");
+  const auto *port_str =
+    caosdb::utility::get_env_var("CAOSDB_SERVER_GRPC_PORT_HTTPS", "8443");
   auto port = std::stoi(port_str);
-  const auto host =
-    caosdb::utils::get_env_var("CAOSDB_SERVER_HOST", "localhost");
+  const auto *const host =
+    caosdb::utility::get_env_var("CAOSDB_SERVER_HOST", "localhost");
   const auto path =
-    caosdb::utils::get_env_var("CAOSDB_SERVER_CERT", std::string());
+    caosdb::utility::get_env_var("CAOSDB_SERVER_CERT", std::string());
   const auto *const user = "not-a-user-23461237";
   const auto *const password = "very-c-cred";
 
-  auto auth = std::make_shared<PlainPasswordAuthenticator>(user, password);
-  auto ssloptions = std::make_shared<PemFileCACertProvider>(path);
-  auto config =
-    std::make_shared<SslCaosDBConnectionConfig>(host, port, ssloptions, auth);
-  auto connection = CaosDBConnection(config);
+  auto auth = PlainPasswordAuthenticator(user, password);
+  auto cert = PemFileCertificateProvider(path);
+  auto config = TlsConnectionConfiguration(host, port, cert, auth);
+  auto connection = Connection(config);
 
   EXPECT_THROW_MESSAGE(connection.GetVersionInfo(), AuthenticationError,
                        "Authentication failed. Username or password wrong.");
 }
 
 TEST(test_connection, connection_ssl_authentication_success) {
-  const auto &pConnection = get_test_connection();
+  const auto &connection = ConnectionManager::GetDefaultConnection();
 
-  auto major = 0;
-  auto minor = 5;
-  const auto *const pre_release = "GRPC004";
+  auto major = caosdb::COMPATIBLE_SERVER_VERSION_MAJOR;
+  auto minor = caosdb::COMPATIBLE_SERVER_VERSION_MINOR;
+  const auto pre_release =
+    std::string(caosdb::COMPATIBLE_SERVER_VERSION_PRE_RELEASE);
 
-  auto v_info = pConnection->GetVersionInfo();
+  auto v_info = connection->GetVersionInfo();
   EXPECT_EQ(major, v_info->GetMajor());
   EXPECT_EQ(minor, v_info->GetMinor());
   EXPECT_EQ(pre_release, v_info->GetPreRelease());
diff --git a/test/test_connection.h b/test/test_connection.h
deleted file mode 100644
index 9c60f4526761b726896e44e125973e853918faf8..0000000000000000000000000000000000000000
--- a/test/test_connection.h
+++ /dev/null
@@ -1,79 +0,0 @@
-/*
- * This file is a part of the CaosDB Project.
- *
- * Copyright (C) 2021 Timm Fitschen <t.fitschen@indiscale.com>
- * Copyright (C) 2021 IndiScale GmbH <info@indiscale.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as
- * published by the Free Software Foundation, either version 3 of the
- * License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see <https://www.gnu.org/licenses/>.
- *
- */
-#include <memory>                  // for allocator, make_shared, shared_ptr
-#include <string>                  // for stoi, string
-#include "caosdb/authentication.h" // for PlainPasswordAuthenticator
-#include "caosdb/connection.h"     // for PemFileCACertProvider, SslCaosDBC...
-#include "caosdb/utils.h"          // for get_env_var
-
-namespace caosdb::connection {
-using caosdb::authentication::PlainPasswordAuthenticator;
-
-/**
- * Return a fresh CaosDBConnection pointer. The caller has the ownership.
- */
-inline auto create_test_connection() -> CaosDBConnection * {
-  auto port_str =
-    caosdb::utils::get_env_var("CAOSDB_SERVER_GRPC_PORT_HTTPS", "8443");
-  auto port = std::stoi(port_str);
-  const auto host =
-    caosdb::utils::get_env_var("CAOSDB_SERVER_HOST", "localhost");
-  const auto path =
-    caosdb::utils::get_env_var("CAOSDB_SERVER_CERT", std::string());
-  const auto user = caosdb::utils::get_env_var("CAOSDB_USER", "admin");
-  const auto password = caosdb::utils::get_env_var("CAOSDB_PASSWORD", "caosdb");
-
-  auto auth = std::make_shared<PlainPasswordAuthenticator>(user, password);
-  auto ssloptions = std::make_shared<PemFileCACertProvider>(path);
-  auto config =
-    std::make_shared<SslCaosDBConnectionConfig>(host, port, ssloptions, auth);
-  return new CaosDBConnection(config);
-};
-
-/**
- * Singleton which holds a single global CaosDBConnection
- */
-class ConnectionProvider {
-private:
-  std::shared_ptr<CaosDBConnection> connection;
-  ConnectionProvider() : connection(create_test_connection()){};
-
-public:
-  static ConnectionProvider &GetInstance() {
-    static ConnectionProvider instance;
-    return instance;
-  };
-  inline auto GetConnection() -> std::shared_ptr<CaosDBConnection> & {
-    return this->connection;
-  }
-
-  ConnectionProvider(ConnectionProvider const &) = delete;
-  void operator=(ConnectionProvider const &) = delete;
-};
-
-/**
- * Return a connection for testing purposes.
- */
-inline auto get_test_connection() -> const std::shared_ptr<CaosDBConnection> & {
-  return ConnectionProvider::GetInstance().GetConnection();
-};
-
-} // namespace caosdb::connection
diff --git a/test/test_transaction.cpp b/test/test_transaction.cpp
index 15901dfdac7dbec8e0e1bc5952693ce994649fba..ec59df9e692416d727529f3c320583be99f6b8f8 100644
--- a/test/test_transaction.cpp
+++ b/test/test_transaction.cpp
@@ -25,12 +25,12 @@
 #include "caosdb/entity.h"         // for Entity, EntityID
 #include "caosdb/transaction.h"    // for Transaction, UniqueResult, Entity
 #include "gtest/gtest_pred_impl.h" // for Test, TestInfo, EXPECT_EQ, TEST
-#include "test_connection.h"       // for get_test_connection
 
 namespace caosdb::transaction {
 
 TEST(test_transaction, DISABLED_retrieve_manufacturer_by_id) {
-  const auto &connection = caosdb::connection::get_test_connection();
+  const auto &connection =
+    caosdb::connection::ConnectionManager::GetDefaultConnection();
 
   const auto *id = "107";
   const auto *role = "RecordType";