diff --git a/src/lib/y2network/network_manager/config_writer.rb b/src/lib/y2network/network_manager/config_writer.rb
index 1a500402c..ab58eda1e 100644
--- a/src/lib/y2network/network_manager/config_writer.rb
+++ b/src/lib/y2network/network_manager/config_writer.rb
@@ -35,7 +35,7 @@ class ConfigWriter < Y2Network::ConfigWriter
       def write_connections(config, _old_config)
         writer = Y2Network::NetworkManager::ConnectionConfigWriter.new
         config.connections.each do |conn|
-          writer.write(conn, nil) # FIXME
+          writer.write(conn, nil, config.routing.routes) # FIXME
         end
       end
     end
diff --git a/src/lib/y2network/network_manager/connection_config_writer.rb b/src/lib/y2network/network_manager/connection_config_writer.rb
index ddb762f71..f9a40f91c 100644
--- a/src/lib/y2network/network_manager/connection_config_writer.rb
+++ b/src/lib/y2network/network_manager/connection_config_writer.rb
@@ -17,9 +17,12 @@
 # To contact SUSE LLC about this file by physical or electronic mail, you may
 # find current contact information at www.suse.com.
 
+require "yast"
 require "cfa/nm_connection"
 require "pathname"
 
+Yast.import "Installation"
+
 module Y2Network
   module NetworkManager
     class ConnectionConfigWriter
@@ -27,23 +30,38 @@ class ConnectionConfigWriter
 
       SYSTEM_CONNECTIONS_PATH = Pathname.new("/etc/NetworkManager/system-connections").freeze
       FILE_EXT = ".nmconnection".freeze
+      # @return [String] base directory
+      attr_reader :basedir
+
+      # Constructor
+      #
+      # @param basedir [String]
+      def initialize(basedir = Yast::Installation.destdir)
+        @basedir = basedir
+      end
 
-      def write(conn, old_conn = nil)
+      def write(conn, old_conn = nil, routes = [])
         return if conn == old_conn
 
-        path = SYSTEM_CONNECTIONS_PATH.join(conn.name).sub_ext(FILE_EXT)
+        path = path_for(conn)
         file = CFA::NmConnection.new(path)
         handler_class = find_handler_class(conn.type)
         return nil if handler_class.nil?
 
         ensure_permissions(path) unless ::File.exist?(path)
 
-        handler_class.new(file).write(conn)
+        handler_class.new(file).write(conn, routes)
         file.save
       end
 
     private
 
+      def path_for(conn)
+        Yast.import "Installation"
+        conn_file_path = SYSTEM_CONNECTIONS_PATH.join(conn.name).sub_ext(FILE_EXT)
+        Pathname.new(File.join(basedir, conn_file_path))
+      end
+
       def ensure_permissions(path)
         ::FileUtils.touch(path)
         ::File.chmod(0o600, path)
diff --git a/src/lib/y2network/network_manager/connection_config_writers/base.rb b/src/lib/y2network/network_manager/connection_config_writers/base.rb
index 1b6274f85..86f3240bf 100644
--- a/src/lib/y2network/network_manager/connection_config_writers/base.rb
+++ b/src/lib/y2network/network_manager/connection_config_writers/base.rb
@@ -40,23 +40,36 @@ def initialize(file)
         # Writes connection information to the interface configuration file
         #
         # @param conn [Y2Network::ConnectionConfig::Base] Connection to take settings from
-        def write(conn)
+        # @param routes [<Array<Route>]
+        def write(conn, routes = [])
           file.connection["id"] = conn.name
           file.connection["autoconnect"] = "false" if ["manual", "off"].include? conn.startmode.name
           file.connection["permissions"] = nil
           file.connection["interface-name"] = conn.interface
           file.connection["zone"] = conn.firewall_zone unless ["", nil].include? conn.firewall_zone
-          conn.bootproto.dhcp? ? configure_dhcp(conn) : add_ips(conn)
+          conn.bootproto.dhcp? ? configure_dhcp(conn) : configure_ips(conn)
+          configure_routes(conn, routes)
           update_file(conn)
         end
 
       private
 
+        def configure_routes(conn, routes)
+          routes.select { |r| (r.interface&.name == conn.name) && r.is_default? }.each do |route|
+            configure_gateway(route)
+          end
+        end
+
+        def configure_gateway(route)
+          section = route.gateway.ipv4? ? file.ipv4 : file.ipv6
+          section["gateway"] = route.gateway.to_s
+        end
+
         # FIXME: Gateway is missing
         # Convenience method for writing the static IP configuration
         #
         # @param conn [Y2Network::ConnectionConfig::Base] Connection to take settings from
-        def add_ips(conn)
+        def configure_ips(conn)
           ips_to_add = conn.ip_aliases.clone
           ips_to_add.append(conn.ip) if conn.ip
           ipv4 = ips_to_add.select { |i| i&.address&.ipv4? }.map { |i| i.address.to_s }
diff --git a/src/lib/y2network/sysconfig/config_writer.rb b/src/lib/y2network/sysconfig/config_writer.rb
index d53524146..73e59d2c6 100644
--- a/src/lib/y2network/sysconfig/config_writer.rb
+++ b/src/lib/y2network/sysconfig/config_writer.rb
@@ -107,7 +107,7 @@ def find_routes_for_iface(iface, routes)
       #
       # @param iface  [Interface,nil] Interface to search routes for; nil will
       #   return the global routes file
-      # @return [Y2Network::ConfigWriters::RoutesFile]
+      # @return [CFA::RoutesFile]
       def routes_file_for(iface)
         return CFA::RoutesFile.new unless iface
 
diff --git a/test/y2network/network_manager/config_writer_test.rb b/test/y2network/network_manager/config_writer_test.rb
index a8fcc5b4f..d064252ad 100644
--- a/test/y2network/network_manager/config_writer_test.rb
+++ b/test/y2network/network_manager/config_writer_test.rb
@@ -71,7 +71,7 @@
     end
 
     it "writes connections configuration" do
-      expect(conn_config_writer).to receive(:write).with(eth0_conn, nil)
+      expect(conn_config_writer).to receive(:write).with(eth0_conn, nil, [])
       writer.write(config)
     end
   end
diff --git a/test/y2network/network_manager/connection_config_writer_test.rb b/test/y2network/network_manager/connection_config_writer_test.rb
index 5e68bc846..78d2c5acd 100644
--- a/test/y2network/network_manager/connection_config_writer_test.rb
+++ b/test/y2network/network_manager/connection_config_writer_test.rb
@@ -75,7 +75,7 @@
 
     it "uses the appropiate handler" do
       expect(writer).to receive(:require).and_return(handler)
-      expect(handler).to receive(:write).with(conn)
+      expect(handler).to receive(:write).with(conn, [])
       writer.write(conn)
     end