diff --git a/include/sqlpp11/connection.h b/include/sqlpp11/connection.h
index 2291c2ea..bb3b8f98 100644
--- a/include/sqlpp11/connection.h
+++ b/include/sqlpp11/connection.h
@@ -37,7 +37,7 @@ namespace sqlpp
   };
 
   // Normal (non-pooled) connection
-  template<typename ConnectionBase>
+  template <typename ConnectionBase>
   class normal_connection : public ConnectionBase
   {
   public:
@@ -46,8 +46,15 @@ namespace sqlpp
 
     // Constructors
     normal_connection() = default;
-    normal_connection(const _config_t& config);
-    normal_connection(const _config_ptr_t& config);
+
+    normal_connection(const _config_t& config) : normal_connection{std::make_shared<_config_t>(config)}
+    {
+    }
+
+    normal_connection(const _config_ptr_t& config) : ConnectionBase{std::make_unique<_handle_t>(config)}
+    {
+    }
+
     normal_connection(const normal_connection&) = delete;
     normal_connection(normal_connection&&) = default;
 
@@ -56,36 +63,21 @@ namespace sqlpp
     normal_connection& operator=(normal_connection&&) = default;
 
     // creates a connection handle and connects to database
-    void connectUsing(const _config_ptr_t& config) noexcept(false);
+    void connectUsing(const _config_ptr_t& config) noexcept(false)
+    {
+      ConnectionBase::_handle = std::make_unique<_handle_t>(config);
+    }
 
   private:
     using _handle_t = typename ConnectionBase::_handle_t;
   };
 
-  template<typename ConnectionBase>
-  normal_connection<ConnectionBase>::normal_connection(const _config_t& config) :
-    normal_connection{std::make_shared<_config_t>(config)}
-  {
-  }
-
-  template<typename ConnectionBase>
-  normal_connection<ConnectionBase>::normal_connection(const _config_ptr_t& config) :
-    ConnectionBase{std::make_unique<_handle_t>(config)}
-  {
-  }
-
-  template<typename ConnectionBase>
-  void normal_connection<ConnectionBase>::connectUsing(const _config_ptr_t& config) noexcept(false)
-  {
-    ConnectionBase::_handle = std::make_unique<_handle_t>(config);
-  }
-
   // Forward declaration
-  template<typename ConnectionBase>
+  template <typename ConnectionBase>
   class connection_pool;
 
   // Pooled connection
-  template<typename ConnectionBase>
+  template <typename ConnectionBase>
   class pooled_connection : public ConnectionBase
   {
     friend class connection_pool<ConnectionBase>::pool_core;
@@ -99,59 +91,47 @@ namespace sqlpp
     // Copy/Move constructors
     pooled_connection(const pooled_connection&) = delete;
     pooled_connection(pooled_connection&& other) = default;
-    ~pooled_connection();
+
+    ~pooled_connection()
+    {
+      conn_release();
+    }
 
     // Assigment operators
     pooled_connection& operator=(const pooled_connection&) = delete;
-    pooled_connection& operator=(pooled_connection&& other);
+
+    pooled_connection& operator=(pooled_connection&& other)
+    {
+      if (this != &other)
+      {
+        conn_release();
+        static_cast<ConnectionBase&>(*this) = std::move(static_cast<ConnectionBase&>(other));
+        _pool_core = std::move(other._pool_core);
+      }
+      return *this;
+    }
 
   private:
     _pool_core_ptr_t _pool_core;
 
     // Constructors used by the connection pool
-    pooled_connection(_handle_ptr_t&& handle, _pool_core_ptr_t pool_core);
-    pooled_connection(const _config_ptr_t& config, _pool_core_ptr_t pool_core);
+    pooled_connection(_handle_ptr_t&& handle, _pool_core_ptr_t pool_core)
+        : ConnectionBase{std::move(handle)}, _pool_core{pool_core}
+    {
+    }
 
-    void conn_release();
+    pooled_connection(const _config_ptr_t& config, _pool_core_ptr_t pool_core)
+        : ConnectionBase{std::make_unique<_handle_t>(config)}, _pool_core{pool_core}
+    {
+    }
+
+    void conn_release()
+    {
+      if (_pool_core)
+      {
+        _pool_core->put(ConnectionBase::_handle);
+        _pool_core = nullptr;
+      }
+    }
   };
-
-  template<typename ConnectionBase>
-  pooled_connection<ConnectionBase>::~pooled_connection()
-  {
-    conn_release();
-  }
-
-  template<typename ConnectionBase>
-  pooled_connection<ConnectionBase>& pooled_connection<ConnectionBase>::operator=(pooled_connection&& other)
-  {
-    if (this != &other) {
-      conn_release();
-      static_cast<ConnectionBase&>(*this) = std::move(static_cast<ConnectionBase&>(other));
-      _pool_core = std::move(other._pool_core);
-    }
-    return *this;
-  }
-
-  template<typename ConnectionBase>
-  pooled_connection<ConnectionBase>::pooled_connection(_handle_ptr_t&& handle, _pool_core_ptr_t pool_core) :
-    ConnectionBase{std::move(handle)},
-    _pool_core{pool_core}
-  {
-  }
-
-  template<typename ConnectionBase>
-  pooled_connection<ConnectionBase>::pooled_connection(const _config_ptr_t& config, _pool_core_ptr_t pool_core) :
-    ConnectionBase{std::make_unique<_handle_t>(config)},
-    _pool_core{pool_core}
-  {
-  }
-
-  template<typename ConnectionBase>
-  void pooled_connection<ConnectionBase>::conn_release()
-  {
-    if (_pool_core) {
-      _pool_core->put(ConnectionBase::_handle);
-      _pool_core = nullptr;
-    }
-  }
 }  // namespace sqlpp
diff --git a/include/sqlpp11/connection_pool.h b/include/sqlpp11/connection_pool.h
index 6fb044d5..bccf395e 100644
--- a/include/sqlpp11/connection_pool.h
+++ b/include/sqlpp11/connection_pool.h
@@ -33,7 +33,7 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 namespace sqlpp
 {
-  template<typename ConnectionBase>
+  template <typename ConnectionBase>
   class connection_pool
   {
   public:
@@ -44,18 +44,50 @@ namespace sqlpp
     class pool_core : public std::enable_shared_from_this<pool_core>
     {
     public:
-      pool_core(const _config_ptr_t& connection_config, std::size_t capacity);
+      pool_core(const _config_ptr_t& connection_config, std::size_t capacity)
+          : _connection_config{connection_config}, _handles{capacity}
+      {
+      }
+
       pool_core() = delete;
-      pool_core(const pool_core &) = delete;
-      pool_core(pool_core &&) = delete;
+      pool_core(const pool_core&) = delete;
+      pool_core(pool_core&&) = delete;
 
       pool_core& operator=(const pool_core&) = delete;
       pool_core& operator=(pool_core&&) = delete;
 
-      _pooled_connection_t get();
-      void put(_handle_ptr_t& handle);
+      _pooled_connection_t get()
+      {
+        std::unique_lock<std::mutex> lock{_mutex};
+        if (_handles.empty())
+        {
+          lock.unlock();
+          return _pooled_connection_t{_connection_config, this->shared_from_this()};
+        }
+        auto handle = std::move(_handles.front());
+        _handles.pop_front();
+        lock.unlock();
+        // If the fetched connection is dead, drop it and create a new one on the fly
+        return handle->check_connection() ? _pooled_connection_t{std::move(handle), this->shared_from_this()}
+                                          : _pooled_connection_t{_connection_config, this->shared_from_this()};
+      }
+
+      void put(_handle_ptr_t& handle)
+      {
+        std::unique_lock<std::mutex> lock{_mutex};
+        if (_handles.full())
+        {
+          _handles.set_capacity(_handles.capacity() + 5);
+        }
+        _handles.push_back(std::move(handle));
+      }
+
       // Returns number of connections available in the pool. Only used in tests.
-      std::size_t available();
+      std::size_t available()
+      {
+        std::unique_lock<std::mutex> lock{_mutex};
+        return _handles.size();
+      }
 
     private:
       _config_ptr_t _connection_config;
@@ -64,88 +96,39 @@ namespace sqlpp
     };
 
     connection_pool() = default;
-    connection_pool(const _config_ptr_t& connection_config, std::size_t capacity);
+
+    connection_pool(const _config_ptr_t& connection_config, std::size_t capacity)
+        : _core{std::make_shared<pool_core>(connection_config, capacity)}
+    {
+    }
+
     connection_pool(const connection_pool&) = delete;
     connection_pool(connection_pool&&) = default;
 
     connection_pool& operator=(const connection_pool&) = delete;
     connection_pool& operator=(connection_pool&&) = default;
 
-    void initialize(const _config_ptr_t& connection_config, std::size_t capacity);
-    _pooled_connection_t get();
+    void initialize(const _config_ptr_t& connection_config, std::size_t capacity)
+    {
+      if (_core)
+      {
+        throw std::runtime_error{"Connection pool already initialized"};
+      }
+      _core = std::make_shared<pool_core>(connection_config, capacity);
+    }
+
+    _pooled_connection_t get()
+    {
+      return _core->get();
+    }
+
     // Returns number of connections available in the pool. Only used in tests.
-    std::size_t available();
+    std::size_t available()
+    {
+      return _core->available();
+    }
 
   private:
     std::shared_ptr<pool_core> _core;
   };
-
-  template<typename ConnectionBase>
-  connection_pool<ConnectionBase>::pool_core::pool_core(const _config_ptr_t& connection_config, std::size_t capacity) :
-    _connection_config{connection_config},
-    _handles{capacity}
-  {
-  }
-
-  template<typename ConnectionBase>
-  typename connection_pool<ConnectionBase>::_pooled_connection_t connection_pool<ConnectionBase>::pool_core::get()
-  {
-    std::unique_lock<std::mutex> lock{_mutex};
-    if (_handles.empty()) {
-      lock.unlock();
-      return _pooled_connection_t{_connection_config, this->shared_from_this()};
-    }
-    auto handle = std::move(_handles.front());
-    _handles.pop_front();
-    lock.unlock();
-    // If the fetched connection is dead, drop it and create a new one on the fly
-    return
-      handle->check_connection() ?
-      _pooled_connection_t{std::move(handle), this->shared_from_this()} :
-      _pooled_connection_t{_connection_config, this->shared_from_this()};
-  }
-
-  template<typename ConnectionBase>
-  void connection_pool<ConnectionBase>::pool_core::put(_handle_ptr_t& handle)
-  {
-    std::unique_lock<std::mutex> lock{_mutex};
-    if (_handles.full ()) {
-            _handles.set_capacity (_handles.capacity () + 5);
-    }
-    _handles.push_back(std::move(handle));
-  }
-
-  template<typename ConnectionBase>
-  std::size_t connection_pool<ConnectionBase>::pool_core::available()
-  {
-    std::unique_lock<std::mutex> lock{_mutex};
-    return _handles.size();
-  }
-
-  template<typename ConnectionBase>
-  connection_pool<ConnectionBase>::connection_pool(const _config_ptr_t& connection_config, std::size_t capacity) :
-    _core{std::make_shared<pool_core>(connection_config, capacity)}
-  {
-  }
-
-  template<typename ConnectionBase>
-  void connection_pool<ConnectionBase>::initialize(const _config_ptr_t& connection_config, std::size_t capacity)
-  {
-    if (_core) {
-      throw std::runtime_error{"Connection pool already initialized"};
-    }
-    _core = std::make_shared<pool_core>(connection_config, capacity);
-  }
-
-  template<typename ConnectionBase>
-  typename connection_pool<ConnectionBase>::_pooled_connection_t connection_pool<ConnectionBase>::get()
-  {
-    return _core->get();
-  }
-
-  template<typename ConnectionBase>
-  std::size_t connection_pool<ConnectionBase>::available()
-  {
-    return _core->available();
-  }
-} // namespace sqlpp
+}  // namespace sqlpp