diff --git a/modules/appmodel/CMakeLists.txt b/modules/appmodel/CMakeLists.txt
index 2bb5efe5d1..fee01a875c 100644
--- a/modules/appmodel/CMakeLists.txt
+++ b/modules/appmodel/CMakeLists.txt
@@ -11,7 +11,9 @@ set (APPMODEL_SOURCES
     appmodel-context.c
     app-object-generator.c
     app-parser-generator.c
+    app-transform-generator.c
     application.c
+    transformation.c
 )
 
 add_module(
diff --git a/modules/appmodel/Makefile.am b/modules/appmodel/Makefile.am
index f87ac90a78..5405ef2bb9 100644
--- a/modules/appmodel/Makefile.am
+++ b/modules/appmodel/Makefile.am
@@ -14,8 +14,12 @@ modules_appmodel_libappmodel_la_SOURCES	=	\
 	modules/appmodel/app-object-generator.h \
 	modules/appmodel/app-parser-generator.c \
 	modules/appmodel/app-parser-generator.h \
+	modules/appmodel/app-transform-generator.c \
+	modules/appmodel/app-transform-generator.h \
 	modules/appmodel/application.c		\
 	modules/appmodel/application.h		\
+	modules/appmodel/transformation.c	\
+	modules/appmodel/transformation.h	\
 	modules/appmodel/appmodel-grammar.y
 
 modules_appmodel_libappmodel_la_CPPFLAGS	=	\
diff --git a/modules/appmodel/app-parser-generator.c b/modules/appmodel/app-parser-generator.c
index 26821d0c21..0fd1958cf6 100644
--- a/modules/appmodel/app-parser-generator.c
+++ b/modules/appmodel/app-parser-generator.c
@@ -1,19 +1,19 @@
 /*
  * Copyright (c) 2017 Balabit
  * Copyright (c) 2017 Balazs Scheidler <balazs.scheidler@balabit.com>
+ * Copyright (c) 2024 Balazs Scheidler <balazs.scheidler@axoflow.com>
  *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, or (at your option) any later version.
  *
- * This library is distributed in the hope that it will be useful,
+ * 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
- * Lesser General Public License for more details.
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
  *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  *
  * As an additional exemption you are allowed to compile & link against the
@@ -98,18 +98,36 @@ _generate_parser(AppParserGenerator *self, const gchar *parser_expr)
                            "            };\n", parser_expr);
 }
 
+static void
+_generate_filterx(AppParserGenerator *self, const gchar *filterx_expr)
+{
+  if (filterx_expr)
+    g_string_append_printf(self->block,
+                           "            filterx {\n"
+                           "                %s\n"
+                           "            };\n", filterx_expr);
+}
+
 static void
 _generate_action(AppParserGenerator *self, Application *app)
 {
-  if (!self->allow_overlaps)
-    {
-      g_string_append_printf(self->block,
-                             "            rewrite {\n"
-                             "                set-tag('.app.%s');\n"
-                             "                set('%s' value('.app.name'));\n"
-                             "            };\n",
-                             app->super.name, app->super.name);
-    }
+  if (self->allow_overlaps)
+    return;
+
+  if (app->filterx_expr)
+    g_string_append_printf(self->block,
+                           "            filterx {\n"
+                           "                meta.app_name = '%s';\n"
+                           "            };\n",
+                           app->super.name);
+
+  else
+    g_string_append_printf(self->block,
+                           "            rewrite {\n"
+                           "                set-tag('.app.%s');\n"
+                           "                set('%s' value('.app.name'));\n"
+                           "            };\n",
+                           app->super.name, app->super.name);
 }
 
 static void
@@ -147,6 +165,7 @@ _generate_application(Application *app, gpointer user_data)
 
   _generate_filter(self, app->filter_expr);
   _generate_parser(self, app->parser_expr);
+  _generate_filterx(self, app->filterx_expr);
   _generate_action(self, app);
   g_string_append_printf(self->block,
                          "            #End Application %s\n", app->super.name);
@@ -175,7 +194,7 @@ _generate_framing(AppParserGenerator *self, GlobalConfig *cfg)
         g_string_append(self->block, "        channel {\n");
 
       g_string_append(self->block,
-                      "            filter { tags('.app.doesnotexist'); };\n"
+                      "            filterx { false; };\n"
                       "        };\n");
     }
   else
@@ -190,7 +209,7 @@ _generate_framing(AppParserGenerator *self, GlobalConfig *cfg)
 static void
 _generate_empty_frame(AppParserGenerator *self)
 {
-  g_string_append(self->block, "channel { filter { tags('.app.doesnotexist'); }; };");
+  g_string_append(self->block, "channel { filterx { false; }; };");
 }
 
 void
diff --git a/modules/appmodel/app-parser-generator.h b/modules/appmodel/app-parser-generator.h
index ea45d5e468..d3b78157be 100644
--- a/modules/appmodel/app-parser-generator.h
+++ b/modules/appmodel/app-parser-generator.h
@@ -22,8 +22,8 @@
  *
  */
 
-#ifndef APPMODEL_APPPARSER_GENERATOR_H_INCLUDED
-#define APPMODEL_APPPARSER_GENERATOR_H_INCLUDED
+#ifndef APPMODEL_APP_PARSER_GENERATOR_H_INCLUDED
+#define APPMODEL_APP_PARSER_GENERATOR_H_INCLUDED
 
 #include "plugin.h"
 
diff --git a/modules/appmodel/app-transform-generator.c b/modules/appmodel/app-transform-generator.c
new file mode 100644
index 0000000000..7c04a2cb61
--- /dev/null
+++ b/modules/appmodel/app-transform-generator.c
@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 2024 Balazs Scheidler <balazs.scheidler@axoflow.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * As an additional exemption you are allowed to compile & link against the
+ * OpenSSL libraries as published by the OpenSSL project. See the file
+ * COPYING for details.
+ *
+ */
+
+#include "app-object-generator.h"
+#include "appmodel.h"
+
+/* app-transform() */
+
+typedef struct _AppTransformGenerator
+{
+  AppObjectGenerator super;
+  const gchar *flavour;
+  GString *block;
+} AppTransformGenerator;
+
+static gboolean
+_parse_transforms_arg(AppTransformGenerator *self, CfgArgs *args, const gchar *reference)
+{
+  self->flavour = cfg_args_get(args, "flavour");
+  if (!self->flavour)
+    self->flavour = "default";
+  return TRUE;
+}
+
+static gboolean
+app_transform_generator_parse_arguments(AppObjectGenerator *s, CfgArgs *args, const gchar *reference)
+{
+  AppTransformGenerator *self = (AppTransformGenerator *) s;
+  g_assert(args != NULL);
+
+  if (!_parse_transforms_arg(self, args, reference))
+    return FALSE;
+
+  if (!app_object_generator_parse_arguments_method(&self->super, args, reference))
+    return FALSE;
+
+  return TRUE;
+}
+
+static void
+_generate_steps(AppTransformGenerator *self, GList *steps)
+{
+  for (GList *l = steps; l; l = l->next)
+    {
+      TransformationStep *step = l->data;
+      g_string_append_printf(self->block, "        # step: %s", step->name);
+      g_string_append_printf(self->block, "        %s\n", step->expr);
+    }
+}
+
+static void
+_generate_app_transform(Transformation *transformation, gpointer user_data)
+{
+  AppTransformGenerator *self = (AppTransformGenerator *) user_data;
+
+  if (strcmp(transformation->super.instance, self->flavour) != 0)
+    return;
+
+  if (!app_object_generator_is_application_included(&self->super, transformation->super.name))
+    return;
+
+  if (app_object_generator_is_application_excluded(&self->super, transformation->super.name))
+    return;
+
+  g_string_append_printf(self->block, "\n#Start Application %s\n", transformation->super.name);
+  g_string_append_printf(self->block,     "    if (meta.app_name == '%s') {\n", transformation->super.name);
+  for (GList *l = transformation->blocks; l; l = l->next)
+    {
+      TransformationBlock *block = l->data;
+
+      _generate_steps(self, block->steps);
+    }
+  g_string_append(self->block,            "    };\n");
+  g_string_append_printf(self->block, "\n#End Application %s\n", transformation->super.name);
+}
+
+
+static void
+app_transform_generate_config(AppObjectGenerator *s, GlobalConfig *cfg, GString *result)
+{
+  AppTransformGenerator *self = (AppTransformGenerator *) s;
+
+  self->block = result;
+  g_string_append_printf(result, "## app-transform(flavour(%s))\n"
+                         "channel {\n"
+                         "    filterx {\n", self->flavour);
+  appmodel_iter_transformations(cfg, _generate_app_transform, self);
+  g_string_append(result,        "    };\n"
+                  "}");
+  self->block = NULL;
+}
+
+CfgBlockGenerator *
+app_transform_generator_new(gint context, const gchar *name)
+{
+  AppTransformGenerator *self = g_new0(AppTransformGenerator, 1);
+
+  app_object_generator_init_instance(&self->super, context, name);
+  self->super.parse_arguments = app_transform_generator_parse_arguments;
+  self->super.generate_config = app_transform_generate_config;
+  return &self->super.super;
+}
diff --git a/modules/appmodel/app-transform-generator.h b/modules/appmodel/app-transform-generator.h
new file mode 100644
index 0000000000..404ec2dfc9
--- /dev/null
+++ b/modules/appmodel/app-transform-generator.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2024 Balazs Scheidler <balazs.scheidler@axoflow.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * As an additional exemption you are allowed to compile & link against the
+ * OpenSSL libraries as published by the OpenSSL project. See the file
+ * COPYING for details.
+ *
+ */
+
+#ifndef APPMODEL_APP_TRANSFORM_GENERATOR_H_INCLUDED
+#define APPMODEL_APP_TRANSFORM_GENERATOR_H_INCLUDED
+
+#include "plugin.h"
+
+CfgBlockGenerator *app_transform_generator_new(gint context, const gchar *name);
+
+#endif
diff --git a/modules/appmodel/application.c b/modules/appmodel/application.c
index 11b32ea20d..672ba4d8c9 100644
--- a/modules/appmodel/application.c
+++ b/modules/appmodel/application.c
@@ -37,12 +37,20 @@ application_set_parser(Application *self, const gchar *parser_expr)
   self->parser_expr = g_strdup(parser_expr);
 }
 
+void
+application_set_filterx(Application *self, const gchar *filterx_expr)
+{
+  g_free(self->filterx_expr);
+  self->filterx_expr = g_strdup(filterx_expr);
+}
+
 static void
 application_free(AppModelObject *s)
 {
   Application *self = (Application *) s;
   g_free(self->filter_expr);
   g_free(self->parser_expr);
+  g_free(self->filterx_expr);
 }
 
 Application *
diff --git a/modules/appmodel/application.h b/modules/appmodel/application.h
index c8dda0cf5a..944f6c63a0 100644
--- a/modules/appmodel/application.h
+++ b/modules/appmodel/application.h
@@ -33,10 +33,12 @@ typedef struct _Application
   AppModelObject super;
   gchar *filter_expr;
   gchar *parser_expr;
+  gchar *filterx_expr;
 } Application;
 
 void application_set_filter(Application *self, const gchar *filter_expr);
 void application_set_parser(Application *self, const gchar *parser_expr);
+void application_set_filterx(Application *self, const gchar *parser_expr);
 
 Application *application_new(const gchar *name, const gchar *topic);
 
diff --git a/modules/appmodel/appmodel-grammar.ym b/modules/appmodel/appmodel-grammar.ym
index 90eb1ca045..d368c9c33c 100644
--- a/modules/appmodel/appmodel-grammar.ym
+++ b/modules/appmodel/appmodel-grammar.ym
@@ -48,8 +48,12 @@
 /* INCLUDE_DECLS */
 
 %token KW_APPLICATION
+%token KW_TRANSFORMATION
+%token KW_TRANSFORM
+%token KW_STEP
 
 %type	<ptr> application_definition
+%type	<ptr> transformation_definition
 
 %%
 
@@ -60,6 +64,12 @@ start
             *instance = $2;
             YYACCEPT;
           }
+	| LL_CONTEXT_ROOT transformation_definition
+          {
+	    appmodel_register_transformation(configuration, $2);
+            *instance = $2;
+            YYACCEPT;
+          }
         ;
 
 
@@ -84,6 +94,46 @@ application_options
 application_option
 	: KW_FILTER _block_content_context_push LL_BLOCK _block_content_context_pop  { application_set_filter($<ptr>0, $3); free($3); }
 	| KW_PARSER _block_content_context_push LL_BLOCK _block_content_context_pop  { application_set_parser($<ptr>0, $3); free($3); }
+	| KW_FILTERX _block_content_context_push LL_BLOCK _block_content_context_pop  {	application_set_filterx($<ptr>0, $3); free($3); }
+	;
+
+
+transformation_definition
+	: KW_TRANSFORMATION string '[' string ']'
+          <ptr>{
+            $$ = transformation_new($2, $4);
+          }[transformation]
+	  '{' <ptr>{ $$ = $transformation; } transformation_options '}'
+	  {
+	    $$ = $transformation;
+            free($2);
+            free($4);
+          }
+	;
+
+transformation_options
+	: transformation_option semicolons { $<ptr>$ = $<ptr>0; } transformation_options
+	|
+	;
+
+/* $0 is Transformation */
+transformation_option
+        : KW_TRANSFORM '[' string ']' '{' { $<ptr>$ = transformation_block_new($3); } transformation_steps '}'
+          { free($3); transformation_add_block($<ptr>0, $<ptr>6); }
+        ;
+
+/* $0 is TransformationBlock */
+transformation_steps
+	: transformation_step semicolons { $<ptr>$ = $<ptr>0; } transformation_steps
+	|
+	;
+
+/* $0 is TransformationBlock */
+transformation_step
+	: KW_STEP '[' string ']' _block_content_context_push LL_BLOCK _block_content_context_pop
+          {
+	    transformation_block_add_step($<ptr>0, $3, $6); free($3); free($6);
+	  }
 	;
 
 /* INCLUDE_RULES */
diff --git a/modules/appmodel/appmodel-parser.c b/modules/appmodel/appmodel-parser.c
index c72c14edbc..29310fc6b8 100644
--- a/modules/appmodel/appmodel-parser.c
+++ b/modules/appmodel/appmodel-parser.c
@@ -31,7 +31,10 @@ int appmodel_parse(CfgLexer *lexer, gpointer *instance, gpointer arg);
 
 static CfgLexerKeyword appmodel_keywords[] =
 {
-  { "application",  KW_APPLICATION },
+  { "application",     KW_APPLICATION },
+  { "transformation",  KW_TRANSFORMATION },
+  { "transform",       KW_TRANSFORM },
+  { "step",            KW_STEP },
   { NULL }
 };
 
diff --git a/modules/appmodel/appmodel-plugin.c b/modules/appmodel/appmodel-plugin.c
index 7bd8692261..30ba1cbb47 100644
--- a/modules/appmodel/appmodel-plugin.c
+++ b/modules/appmodel/appmodel-plugin.c
@@ -24,6 +24,7 @@
 #include "cfg-parser.h"
 #include "appmodel-parser.h"
 #include "app-parser-generator.h"
+#include "app-transform-generator.h"
 #include "block-ref-parser.h"
 #include "plugin.h"
 #include "plugin-types.h"
@@ -36,6 +37,12 @@ app_parser_construct(Plugin *p)
   return app_parser_generator_new(p->type, p->name);
 }
 
+static gpointer
+app_transform_construct(Plugin *p)
+{
+  return app_transform_generator_new(p->type, p->name);
+}
+
 static Plugin appmodel_plugins[] =
 {
   {
@@ -43,11 +50,22 @@ static Plugin appmodel_plugins[] =
     .name = "application",
     .parser = &appmodel_parser,
   },
+  {
+    .type = LL_CONTEXT_ROOT,
+    .name = "transformation",
+    .parser = &appmodel_parser,
+  },
   {
     .type = LL_CONTEXT_PARSER | LL_CONTEXT_FLAG_GENERATOR,
     .name = "app-parser",
     .construct = app_parser_construct,
     .parser = &block_ref_parser
+  },
+  {
+    .type = LL_CONTEXT_PARSER | LL_CONTEXT_FLAG_GENERATOR,
+    .name = "app-transform",
+    .construct = app_transform_construct,
+    .parser = &block_ref_parser
   }
 };
 
diff --git a/modules/appmodel/appmodel.c b/modules/appmodel/appmodel.c
index e94aea1368..dab106ac52 100644
--- a/modules/appmodel/appmodel.c
+++ b/modules/appmodel/appmodel.c
@@ -53,3 +53,19 @@ appmodel_iter_applications(GlobalConfig *cfg, void (*foreach)(Application *app,
   AppModelContext *appmodel = appmodel_get_context(cfg);
   appmodel_context_iter_objects(appmodel, APPLICATION_TYPE_NAME, (AppModelContextIterFunc) foreach, user_data);
 }
+
+void
+appmodel_register_transformation(GlobalConfig *cfg, Transformation *transformation)
+{
+  AppModelContext *ac = appmodel_get_context(cfg);
+
+  appmodel_context_register_object(ac, &transformation->super);
+}
+
+void
+appmodel_iter_transformations(GlobalConfig *cfg, void (*foreach)(Transformation *transformation, gpointer user_data),
+                              gpointer user_data)
+{
+  AppModelContext *appmodel = appmodel_get_context(cfg);
+  appmodel_context_iter_objects(appmodel, TRANSFORMATION_TYPE_NAME, (AppModelContextIterFunc) foreach, user_data);
+}
diff --git a/modules/appmodel/appmodel.h b/modules/appmodel/appmodel.h
index 34b0f3dd7e..f017f63bba 100644
--- a/modules/appmodel/appmodel.h
+++ b/modules/appmodel/appmodel.h
@@ -25,6 +25,7 @@
 
 #include "module-config.h"
 #include "application.h"
+#include "transformation.h"
 
 AppModelContext *appmodel_get_context(GlobalConfig *cfg);
 void appmodel_register_application(GlobalConfig *cfg, Application *application);
@@ -32,4 +33,8 @@ void appmodel_iter_applications(GlobalConfig *cfg,
                                 void (*foreach)(Application *app, gpointer user_data),
                                 gpointer user_data);
 
+void appmodel_register_transformation(GlobalConfig *cfg, Transformation *transformation);
+void appmodel_iter_transformations(GlobalConfig *cfg, void (*foreach)(Transformation *transformation,
+                                   gpointer user_data), gpointer user_data);
+
 #endif
diff --git a/modules/appmodel/tests/test_app_parser_generator.c b/modules/appmodel/tests/test_app_parser_generator.c
index 1fb7e81c60..b08e0eb881 100644
--- a/modules/appmodel/tests/test_app_parser_generator.c
+++ b/modules/appmodel/tests/test_app_parser_generator.c
@@ -201,7 +201,7 @@ Test(app_parser_generator, app_parser_with_no_apps_registered_generates_empty_fr
 {
   _app_parser_generate("port514");
   _assert_parser_framing_is_present();
-  _assert_snippet_is_present("tags('.app.doesnotexist')");
+  _assert_snippet_is_present("filterx { false; }");
   _assert_config_is_valid("port514", NULL);
 }
 
@@ -223,7 +223,7 @@ Test(app_parser_generator, app_parser_is_disabled_if_auto_parse_is_set_to_no)
   _register_sample_application("bar", "port514");
 
   _app_parser_generate_with_args("port514", _build_cfg_args("auto-parse", "no", NULL));
-  _assert_snippet_is_present("tags('.app.doesnotexist')");
+  _assert_snippet_is_present("filterx { false; }");
 
   _app_parser_generate_with_args("port514", _build_cfg_args("auto-parse", "yes", NULL));
   _assert_parser_framing_is_present();
diff --git a/modules/appmodel/transformation.c b/modules/appmodel/transformation.c
new file mode 100644
index 0000000000..2f6cc0c5cd
--- /dev/null
+++ b/modules/appmodel/transformation.c
@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2023 Balázs Scheidler <balazs.scheidler@axoflow.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * As an additional exemption you are allowed to compile & link against the
+ * OpenSSL libraries as published by the OpenSSL project. See the file
+ * COPYING for details.
+ *
+ */
+
+#include "transformation.h"
+
+/* TransformationStep: a named filterx expression */
+
+TransformationStep *
+transformation_step_new(const gchar *name, const gchar *expr)
+{
+  TransformationStep *self = g_new0(TransformationStep, 1);
+  self->name = g_strdup(name);
+  self->expr = g_strdup(expr);
+  return self;
+}
+
+void
+transformation_step_free(TransformationStep *self)
+{
+  g_free(self->name);
+  g_free(self->expr);
+}
+
+/* TransformationBlock: named list of steps */
+
+void
+transformation_block_add_step(TransformationBlock *self, const gchar *name, const gchar *expr)
+{
+  self->steps = g_list_append(self->steps, transformation_step_new(name, expr));
+}
+
+TransformationBlock *
+transformation_block_new(const gchar *name)
+{
+  TransformationBlock *self = g_new0(TransformationBlock, 1);
+  self->name = g_strdup(name);
+  return self;
+}
+
+void
+transformation_block_free(TransformationBlock *self)
+{
+  g_free(self->name);
+  g_list_free_full(self->steps, (GDestroyNotify) transformation_step_free);
+  g_free(self);
+}
+
+/* Transformation */
+/* list of blocks */
+
+void
+transformation_add_block(Transformation *self, TransformationBlock *block)
+{
+  self->blocks = g_list_append(self->blocks, block);
+}
+
+static void
+transformation_free(AppModelObject *s)
+{
+  Transformation *self = (Transformation *) s;
+
+  g_list_free_full(self->blocks, (GDestroyNotify) transformation_block_free);
+}
+
+Transformation *
+transformation_new(const gchar *app, const gchar *flavour)
+{
+  Transformation *self = g_new0(Transformation, 1);
+
+  appmodel_object_init_instance(&self->super, TRANSFORMATION_TYPE_NAME, app, flavour);
+  self->super.free_fn = transformation_free;
+  return self;
+}
diff --git a/modules/appmodel/transformation.h b/modules/appmodel/transformation.h
new file mode 100644
index 0000000000..07aa31cbda
--- /dev/null
+++ b/modules/appmodel/transformation.h
@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2023 Balázs Scheidler <balazs.scheidler@axoflow.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * As an additional exemption you are allowed to compile & link against the
+ * OpenSSL libraries as published by the OpenSSL project. See the file
+ * COPYING for details.
+ *
+ */
+
+#ifndef APPMODEL_TRANSFORMATION_H_INCLUDED
+#define APPMODEL_TRANSFORMATION_H_INCLUDED
+
+#include "appmodel-context.h"
+
+#define TRANSFORMATION_TYPE_NAME "transformation"
+
+typedef struct _TransformationStep
+{
+  gchar *name;
+  gchar *expr;
+} TransformationStep;
+
+TransformationStep *transformation_step_new(const gchar *name, const gchar *expr);
+void transformation_step_free(TransformationStep *self);
+
+
+typedef struct _TransformationBlock
+{
+  gchar *name;
+  GList *steps;
+} TransformationBlock;
+
+void transformation_block_add_step(TransformationBlock *self, const gchar *name, const gchar *step);
+TransformationBlock *transformation_block_new(const gchar *name);
+void transformation_block_free(TransformationBlock *self);
+
+typedef struct _Transformation
+{
+  AppModelObject super;
+  GList *blocks;
+} Transformation;
+
+void transformation_add_block(Transformation *self, TransformationBlock *block);
+Transformation *transformation_new(const gchar *app, const gchar *name);
+
+#endif
diff --git a/tests/copyright/policy b/tests/copyright/policy
index 999a50192e..3730b3e4a0 100644
--- a/tests/copyright/policy
+++ b/tests/copyright/policy
@@ -271,6 +271,8 @@ modules/kvformat/filterx-func-parse-kv\.[ch]
 modules/kvformat/filterx-func-format-kv\.[ch]
 modules/kvformat/tests/test_filterx_func_parse_kv.c
 modules/kvformat/tests/test_filterx_func_format_kv.c
+modules/appmodel/app-transform-generator\.[ch]$
+modules/appmodel/transformation\.[ch]$
 docker/python-modules/webhook/scl/webhook.conf
 docker/python-modules/webhook/source.py
 packaging/package-indexer/remote_storage_synchronizer/s3_bucket_synchronizer.py