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..dc88a13e8e89ef99d7a4ff37e819dbf9bc6dbd37 100644
--- a/.docker/tester.yml
+++ b/.docker/tester.yml
@@ -3,8 +3,7 @@ services:
   tester:
     image: "$CPPINTTEST_REGISTRY_IMAGE"
     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/test/test_ccaosdb.cpp b/test/test_ccaosdb.cpp
index 7039a6096af1e7337209fafa5c5d8705edea9726..7909ab8830cad441e40fb3b782b35e06f9eb3f1b 100644
--- a/test/test_ccaosdb.cpp
+++ b/test/test_ccaosdb.cpp
@@ -17,26 +17,25 @@
  * 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_connection_create_connection
-#include "gtest/gtest.h"     // for Test, SuiteApiResolver, TestInfo, TEST
-#include "test_connection.h" // for create_test_connection_config
+#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_configuration config;
-  auto wrapped = caosdb::connection::create_test_connection_config();
-  config.wrapped_connection_configuration = wrapped.get();
 
   caosdb_connection_connection connection;
-  caosdb_connection_create_connection(&connection, &config);
+  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();
+  const auto *const pre_release =
+    caosdb_constants_COMPATIBLE_SERVER_VERSION_PRE_RELEASE();
 
   EXPECT_EQ(major, version_info.major);
   EXPECT_EQ(minor, version_info.minor);
diff --git a/test/test_connection.cpp b/test/test_connection.cpp
index f09d6b071802d26b21de1db46e23a2582ec86db1..b69719768e3e4fad2b9d40d87549c7fc70d0020b 100644
--- a/test/test_connection.cpp
+++ b/test/test_connection.cpp
@@ -29,7 +29,6 @@
 #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 {
@@ -106,7 +105,7 @@ TEST(test_connection, connection_ssl_authentication_error_wrong_credentials) {
 }
 
 TEST(test_connection, connection_ssl_authentication_success) {
-  const auto& connection = get_test_connection();
+  const auto &connection = ConnectionManager::GetDefaultConnection();
 
   auto major = caosdb::COMPATIBLE_SERVER_VERSION_MAJOR;
   auto minor = caosdb::COMPATIBLE_SERVER_VERSION_MINOR;
diff --git a/test/test_connection.h b/test/test_connection.h
deleted file mode 100644
index 5e3cf5cb556e3b28134600ebd5dd9f3e5cd7de51..0000000000000000000000000000000000000000
--- a/test/test_connection.h
+++ /dev/null
@@ -1,84 +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 PemFileCertificateProvider, TlsCaosDBC...
-#include "caosdb/utility.h"    // for get_env_var
-
-namespace caosdb::connection {
-using caosdb::authentication::PlainPasswordAuthenticator;
-
-inline auto create_test_connection_config()
-  -> std::unique_ptr<TlsConnectionConfig> {
-  auto port_str =
-    caosdb::utility::get_env_var("CAOSDB_SERVER_GRPC_PORT_HTTPS", "8443");
-  auto port = std::stoi(port_str);
-  const auto host =
-    caosdb::utility::get_env_var("CAOSDB_SERVER_HOST", "localhost");
-  const auto path =
-    caosdb::utility::get_env_var("CAOSDB_SERVER_CERT", std::string());
-  const auto user = caosdb::utility::get_env_var("CAOSDB_USER", "admin");
-  const auto password =
-    caosdb::utility::get_env_var("CAOSDB_PASSWORD", "caosdb");
-
-  auto auth = PlainPasswordAuthenticator(user, password);
-  auto cert = PemFileCertificateProvider(path);
-  return std::make_unique<TlsConnectionConfig>(host, port, cert, auth);
-}
-
-/**
- * Return a fresh Connection pointer. The caller has the ownership.
- */
-inline auto create_test_connection() -> std::unique_ptr<Connection> {
-  auto config = create_test_connection_config();
-  return std::make_unique<Connection>(*(config.get()));
-};
-
-/**
- * Singleton which holds a single global Connection
- */
-class ConnectionProvider {
-private:
-  std::shared_ptr<Connection> connection;
-  ConnectionProvider() : connection(create_test_connection()){};
-
-public:
-  static ConnectionProvider &GetInstance() {
-    static ConnectionProvider instance;
-    return instance;
-  };
-  inline auto GetConnection() -> std::shared_ptr<Connection> & {
-    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<Connection> & {
-  return ConnectionProvider::GetInstance().GetConnection();
-};
-
-} // namespace caosdb::connection
diff --git a/test/test_transaction.cpp b/test/test_transaction.cpp
index 15901dfdac7dbec8e0e1bc5952693ce994649fba..62fa60f8fafbb424333a7828b8d9f71bd9bd0f6f 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();
+TEST(test_transaction, retrieve_manufacturer_by_id) {
+  const auto &connection =
+    caosdb::connection::ConnectionManager::GetDefaultConnection();
 
   const auto *id = "107";
   const auto *role = "RecordType";