diff --git a/docs/ahriman.1 b/docs/ahriman.1
index ba13df92..7b489aab 100644
--- a/docs/ahriman.1
+++ b/docs/ahriman.1
@@ -3,7 +3,7 @@
 ahriman
 .SH SYNOPSIS
 .B ahriman
-[-h] [-a ARCHITECTURE] [-c CONFIGURATION] [--force] [-l LOCK] [--no-report] [-q] [--unsafe] [-V] {aur-search,search,help,help-commands-unsafe,key-import,package-add,add,package-update,package-remove,remove,package-status,status,package-status-remove,package-status-update,status-update,patch-add,patch-list,patch-remove,repo-backup,repo-check,check,repo-clean,clean,repo-config,config,repo-rebuild,rebuild,repo-remove-unknown,remove-unknown,repo-report,report,repo-restore,repo-setup,init,repo-init,setup,repo-sign,sign,repo-status-update,repo-sync,sync,repo-triggers,repo-update,update,shell,user-add,user-list,user-remove,version,web} ...
+[-h] [-a ARCHITECTURE] [-c CONFIGURATION] [--force] [-l LOCK] [--no-report] [-q] [--unsafe] [-V] {aur-search,search,help,help-commands-unsafe,key-import,package-add,add,package-update,package-remove,remove,package-status,status,package-status-remove,package-status-update,status-update,patch-add,patch-list,patch-remove,patch-set-add,repo-backup,repo-check,check,repo-clean,clean,repo-config,config,repo-rebuild,rebuild,repo-remove-unknown,remove-unknown,repo-report,report,repo-restore,repo-setup,init,repo-init,setup,repo-sign,sign,repo-status-update,repo-sync,sync,repo-triggers,repo-update,update,shell,user-add,user-list,user-remove,version,web} ...
 .SH DESCRIPTION
 ArcH linux ReposItory MANager
 
@@ -71,7 +71,7 @@ remove package status
 update package status
 .TP
 \fBahriman\fR \fI\,patch-add\/\fR
-add patch set
+add patch for PKGBUILD function
 .TP
 \fBahriman\fR \fI\,patch-list\/\fR
 list patch sets
@@ -79,6 +79,9 @@ list patch sets
 \fBahriman\fR \fI\,patch-remove\/\fR
 remove patch set
 .TP
+\fBahriman\fR \fI\,patch-set-add\/\fR
+add patch set
+.TP
 \fBahriman\fR \fI\,repo-backup\/\fR
 backup repository data
 .TP
@@ -284,21 +287,25 @@ set status for specified packages. If no packages supplied, service status will
 new status
 
 .SH COMMAND \fI\,'ahriman patch-add'\/\fR
-usage: ahriman patch-add [-h] [-t TRACK] package
+usage: ahriman patch-add [-h] [-p PATCH] package variable
 
-create or update source patches
+create or update patched PKGBUILD function or variable
 
 .TP
 \fBpackage\fR
-path to directory with changed files for patch addition/update
+package base
+
+.TP
+\fBvariable\fR
+PKGBUILD variable or function name. If variable is a function, it must end with ()
 
 .SH OPTIONS \fI\,'ahriman patch-add'\/\fR
 .TP
-\fB\-t\fR \fI\,TRACK\/\fR, \fB\-\-track\fR \fI\,TRACK\/\fR
-files which has to be tracked
+\fB\-p\fR \fI\,PATCH\/\fR, \fB\-\-patch\fR \fI\,PATCH\/\fR
+path to file which contains function or variable value. If not set, the value will be read from stdin
 
 .SH COMMAND \fI\,'ahriman patch-list'\/\fR
-usage: ahriman patch-list [-h] [-e] [package]
+usage: ahriman patch-list [-h] [-e] [-v VARIABLE] [package]
 
 list available patches for the package
 
@@ -311,8 +318,12 @@ package base
 \fB\-e\fR, \fB\-\-exit\-code\fR
 return non\-zero exit status if result is empty
 
+.TP
+\fB\-v\fR \fI\,VARIABLE\/\fR, \fB\-\-variable\fR \fI\,VARIABLE\/\fR
+if set, show only patches for specified PKGBUILD variables
+
 .SH COMMAND \fI\,'ahriman patch-remove'\/\fR
-usage: ahriman patch-remove [-h] package
+usage: ahriman patch-remove [-h] [-v VARIABLE] package
 
 remove patches for the package
 
@@ -320,6 +331,26 @@ remove patches for the package
 \fBpackage\fR
 package base
 
+.SH OPTIONS \fI\,'ahriman patch-remove'\/\fR
+.TP
+\fB\-v\fR \fI\,VARIABLE\/\fR, \fB\-\-variable\fR \fI\,VARIABLE\/\fR
+should be used for single\-function patches in case if you wold like to remove only specified PKGBUILD variables. In case
+if not set, it will remove all patches related to the package
+
+.SH COMMAND \fI\,'ahriman patch-set-add'\/\fR
+usage: ahriman patch-set-add [-h] [-t TRACK] package
+
+create or update source patches
+
+.TP
+\fBpackage\fR
+path to directory with changed files for patch addition/update
+
+.SH OPTIONS \fI\,'ahriman patch-set-add'\/\fR
+.TP
+\fB\-t\fR \fI\,TRACK\/\fR, \fB\-\-track\fR \fI\,TRACK\/\fR
+files which has to be tracked
+
 .SH COMMAND \fI\,'ahriman repo-backup'\/\fR
 usage: ahriman repo-backup [-h] path
 
diff --git a/docs/ahriman.core.database.migrations.rst b/docs/ahriman.core.database.migrations.rst
index 08dc66fb..9fd425af 100644
--- a/docs/ahriman.core.database.migrations.rst
+++ b/docs/ahriman.core.database.migrations.rst
@@ -28,6 +28,14 @@ ahriman.core.database.migrations.m002\_user\_access module
    :no-undoc-members:
    :show-inheritance:
 
+ahriman.core.database.migrations.m003\_patch\_variables module
+--------------------------------------------------------------
+
+.. automodule:: ahriman.core.database.migrations.m003_patch_variables
+   :members:
+   :no-undoc-members:
+   :show-inheritance:
+
 Module contents
 ---------------
 
diff --git a/docs/ahriman.core.formatters.rst b/docs/ahriman.core.formatters.rst
index c3ecda6d..d3b2a849 100644
--- a/docs/ahriman.core.formatters.rst
+++ b/docs/ahriman.core.formatters.rst
@@ -36,6 +36,14 @@ ahriman.core.formatters.package\_printer module
    :no-undoc-members:
    :show-inheritance:
 
+ahriman.core.formatters.patch\_printer module
+---------------------------------------------
+
+.. automodule:: ahriman.core.formatters.patch_printer
+   :members:
+   :no-undoc-members:
+   :show-inheritance:
+
 ahriman.core.formatters.printer module
 --------------------------------------
 
diff --git a/docs/faq.rst b/docs/faq.rst
index 49503eff..99af90d8 100644
--- a/docs/faq.rst
+++ b/docs/faq.rst
@@ -162,11 +162,13 @@ Unlike ``RemotePullTrigger`` trigger, the ``RemotePushTrigger`` more likely will
 But I just wanted to change PKGBUILD from AUR a bit!
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-Well it is supported also.
+Well it is supported also. The recommended way is to patch specific function, e.g. by running ``sudo -u ahriman ahriman patch-add ahriman version``. This command will prompt for new value of the PKGBUILD variable ``version``. You can also write it to file and read from it ``sudo -u ahriman ahriman patch-add ahriman version version.patch``.
+
+Alternatively you can create full-diff patches, which are calculated by using ``git diff`` from current PKGBUILD master branch:
 
 #. Clone sources from AUR.
 #. Make changes you would like to (e.g. edit ``PKGBUILD``, add external patches).
-#. Run ``sudo -u ahriman ahriman patch-add /path/to/local/directory/with/PKGBUILD``.
+#. Run ``sudo -u ahriman ahriman patch-set-add /path/to/local/directory/with/PKGBUILD``.
 
 The last command will calculate diff from current tree to the ``HEAD`` and will store it locally. Patches will be applied on any package actions (e.g. it can be used for dependency management).
 
diff --git a/src/ahriman/application/ahriman.py b/src/ahriman/application/ahriman.py
index 03d79372..7861c971 100644
--- a/src/ahriman/application/ahriman.py
+++ b/src/ahriman/application/ahriman.py
@@ -93,6 +93,7 @@ def _parser() -> argparse.ArgumentParser:
     _set_patch_add_parser(subparsers)
     _set_patch_list_parser(subparsers)
     _set_patch_remove_parser(subparsers)
+    _set_patch_set_add_parser(subparsers)
     _set_repo_backup_parser(subparsers)
     _set_repo_check_parser(subparsers)
     _set_repo_clean_parser(subparsers)
@@ -320,7 +321,7 @@ def _set_package_status_update_parser(root: SubParserAction) -> argparse.Argumen
 
 def _set_patch_add_parser(root: SubParserAction) -> argparse.ArgumentParser:
     """
-    add parser for new patch subcommand
+    add parser for new single-function patch subcommand
 
     Args:
         root(SubParserAction): subparsers for the commands
@@ -328,16 +329,18 @@ def _set_patch_add_parser(root: SubParserAction) -> argparse.ArgumentParser:
     Returns:
         argparse.ArgumentParser: created argument parser
     """
-    parser = root.add_parser("patch-add", help="add patch set", description="create or update source patches",
-                             epilog="In order to add a patch set for the package you will need to clone "
-                                    "the AUR package manually, add required changes (e.g. external patches, "
-                                    "edit PKGBUILD) and run command, e.g. ``ahriman patch path/to/directory``. "
-                                    "By default it tracks *.patch and *.diff files, but this behavior can be changed "
-                                    "by using --track option",
+    parser = root.add_parser("patch-add", help="add patch for PKGBUILD function",
+                             description="create or update patched PKGBUILD function or variable",
+                             epilog="Unlike ``patch-set-add``, this function allows to patch only one PKGBUILD f"
+                                    "unction, e.g. typing ``ahriman patch-add ahriman version`` it will change the "
+                                    "``version`` inside PKGBUILD, typing ``ahriman patch-add ahriman build()`` "
+                                    "it will change ``build()`` function inside PKGBUILD",
                              formatter_class=_formatter)
-    parser.add_argument("package", help="path to directory with changed files for patch addition/update")
-    parser.add_argument("-t", "--track", help="files which has to be tracked", action="append",
-                        default=["*.diff", "*.patch"])
+    parser.add_argument("package", help="package base")
+    parser.add_argument("variable", help="PKGBUILD variable or function name. If variable is a function, "
+                                         "it must end with ()")
+    parser.add_argument("patch", help="path to file which contains function or variable value. If not set, "
+                                      "the value will be read from stdin", type=Path, nargs="?")
     parser.set_defaults(handler=handlers.Patch, action=Action.Update, architecture=[""], lock=None, no_report=True)
     return parser
 
@@ -356,6 +359,8 @@ def _set_patch_list_parser(root: SubParserAction) -> argparse.ArgumentParser:
                              description="list available patches for the package", formatter_class=_formatter)
     parser.add_argument("package", help="package base", nargs="?")
     parser.add_argument("-e", "--exit-code", help="return non-zero exit status if result is empty", action="store_true")
+    parser.add_argument("-v", "--variable", help="if set, show only patches for specified PKGBUILD variables",
+                        action="append")
     parser.set_defaults(handler=handlers.Patch, action=Action.List, architecture=[""], lock=None, no_report=True)
     return parser
 
@@ -373,10 +378,39 @@ def _set_patch_remove_parser(root: SubParserAction) -> argparse.ArgumentParser:
     parser = root.add_parser("patch-remove", help="remove patch set", description="remove patches for the package",
                              formatter_class=_formatter)
     parser.add_argument("package", help="package base")
+    parser.add_argument("-v", "--variable", help="should be used for single-function patches in case if you wold like "
+                                                 "to remove only specified PKGBUILD variables. In case if not set, "
+                                                 "it will remove all patches related to the package",
+                        action="append")
     parser.set_defaults(handler=handlers.Patch, action=Action.Remove, architecture=[""], lock=None, no_report=True)
     return parser
 
 
+def _set_patch_set_add_parser(root: SubParserAction) -> argparse.ArgumentParser:
+    """
+    add parser for new full-diff patch subcommand
+
+    Args:
+        root(SubParserAction): subparsers for the commands
+
+    Returns:
+        argparse.ArgumentParser: created argument parser
+    """
+    parser = root.add_parser("patch-set-add", help="add patch set", description="create or update source patches",
+                             epilog="In order to add a patch set for the package you will need to clone "
+                                    "the AUR package manually, add required changes (e.g. external patches, "
+                                    "edit PKGBUILD) and run command, e.g. ``ahriman patch-set-add path/to/directory``. "
+                                    "By default it tracks *.patch and *.diff files, but this behavior can be changed "
+                                    "by using --track option",
+                             formatter_class=_formatter)
+    parser.add_argument("package", help="path to directory with changed files for patch addition/update", type=Path)
+    parser.add_argument("-t", "--track", help="files which has to be tracked", action="append",
+                        default=["*.diff", "*.patch"])
+    parser.set_defaults(handler=handlers.Patch, action=Action.Update, architecture=[""], lock=None, no_report=True,
+                        variable=None)
+    return parser
+
+
 def _set_repo_backup_parser(root: SubParserAction) -> argparse.ArgumentParser:
     """
     add parser for repository backup subcommand
diff --git a/src/ahriman/application/handlers/patch.py b/src/ahriman/application/handlers/patch.py
index cd9cc432..8d1f34d1 100644
--- a/src/ahriman/application/handlers/patch.py
+++ b/src/ahriman/application/handlers/patch.py
@@ -18,17 +18,19 @@
 # along with this program. If not, see <http://www.gnu.org/licenses/>.
 #
 import argparse
+import sys
 
 from pathlib import Path
-from typing import List, Optional, Type
+from typing import List, Optional, Tuple, Type
 
 from ahriman.application.application import Application
 from ahriman.application.handlers import Handler
 from ahriman.core.build_tools.sources import Sources
 from ahriman.core.configuration import Configuration
-from ahriman.core.formatters import StringPrinter
+from ahriman.core.formatters import PatchPrinter
 from ahriman.models.action import Action
 from ahriman.models.package import Package
+from ahriman.models.pkgbuild_patch import PkgbuildPatch
 
 
 class Patch(Handler):
@@ -52,51 +54,93 @@ class Patch(Handler):
         application = Application(architecture, configuration, no_report, unsafe)
         application.on_start()
 
-        if args.action == Action.List:
-            Patch.patch_set_list(application, args.package, args.exit_code)
+        if args.action == Action.Update and args.variable is not None:
+            patch = Patch.patch_create_from_function(args.variable, args.patch)
+            Patch.patch_set_create(application, args.package, patch)
+        elif args.action == Action.Update and args.variable is None:
+            package_base, patch = Patch.patch_create_from_diff(args.package, args.track)
+            Patch.patch_set_create(application, package_base, patch)
+        elif args.action == Action.List:
+            Patch.patch_set_list(application, args.package, args.variable, args.exit_code)
         elif args.action == Action.Remove:
-            Patch.patch_set_remove(application, args.package)
-        elif args.action == Action.Update:
-            Patch.patch_set_create(application, Path(args.package), args.track)
+            Patch.patch_set_remove(application, args.package, args.variable)
 
     @staticmethod
-    def patch_set_create(application: Application, sources_dir: Path, track: List[str]) -> None:
+    def patch_create_from_diff(sources_dir: Path, track: List[str]) -> Tuple[str, PkgbuildPatch]:
+        """
+        create PKGBUILD plain diff patches from sources directory
+
+        Args:
+            sources_dir(Path): path to directory with the package sources
+            track(List[str]): track files which match the glob before creating the patch
+
+        Returns:
+            Tuple[str, PkgbuildPatch]: package base and created PKGBUILD patch based on the diff from master HEAD
+                to current files
+        """
+        package = Package.from_build(sources_dir)
+        patch = Sources.patch_create(sources_dir, *track)
+        return package.base, PkgbuildPatch(None, patch)
+
+    @staticmethod
+    def patch_create_from_function(variable: str, patch_path: Optional[Path]) -> PkgbuildPatch:
+        """
+        create single-function patch set for the package base
+
+        Args:
+            variable(str): function or variable name inside PKGBUILD
+            patch_path(Path): optional path to patch content. If not set, it will be read from stdin
+
+        Returns:
+            PkgbuildPatch: created patch for the PKGBUILD function
+        """
+        if patch_path is None:
+            print("Post new function or variable value below. Press Ctrl-D to finish:", file=sys.stderr)
+            patch = "".join(list(sys.stdin))
+        else:
+            patch = patch_path.read_text(encoding="utf8")
+        patch = patch.strip()  # remove spaces around the patch
+        return PkgbuildPatch(variable, patch)
+
+    @staticmethod
+    def patch_set_create(application: Application, package_base: str, patch: PkgbuildPatch) -> None:
         """
         create patch set for the package base
 
         Args:
             application(Application): application instance
-            sources_dir(Path): path to directory with the package sources
-            track(List[str]): track files which match the glob before creating the patch
+            package_base(str): package base
+            patch(PkgbuildPatch): patch descriptor
         """
-        package = Package.from_build(sources_dir)
-        patch = Sources.patch_create(sources_dir, *track)
-        application.database.patches_insert(package.base, patch)
+        application.database.patches_insert(package_base, patch)
 
     @staticmethod
-    def patch_set_list(application: Application, package_base: Optional[str], exit_code: bool) -> None:
+    def patch_set_list(application: Application, package_base: Optional[str], variables: List[str],
+                       exit_code: bool) -> None:
         """
         list patches available for the package base
 
         Args:
             application(Application): application instance
             package_base(Optional[str]): package base
+            variables(List[str]): extract patches only for specified PKGBUILD variables
             exit_code(bool): exit with error on empty search result
+            :
         """
-        patches = application.database.patches_list(package_base)
+        patches = application.database.patches_list(package_base, variables)
         Patch.check_if_empty(exit_code, not patches)
 
         for base, patch in patches.items():
-            content = base if package_base is None else patch
-            StringPrinter(content).print(verbose=True)
+            PatchPrinter(base, patch).print(verbose=True, separator=" = ")
 
     @staticmethod
-    def patch_set_remove(application: Application, package_base: str) -> None:
+    def patch_set_remove(application: Application, package_base: str, variables: List[str]) -> None:
         """
         remove patch set for the package base
 
         Args:
             application(Application): application instance
             package_base(str): package base
+            variables(List[str]): remove patches only for specified PKGBUILD variables
         """
-        application.database.patches_remove(package_base)
+        application.database.patches_remove(package_base, variables)
diff --git a/src/ahriman/core/build_tools/sources.py b/src/ahriman/core/build_tools/sources.py
index 77df3b71..8c597d64 100644
--- a/src/ahriman/core/build_tools/sources.py
+++ b/src/ahriman/core/build_tools/sources.py
@@ -45,24 +45,22 @@ class Sources(LazyLogging):
     _check_output = check_output
 
     @staticmethod
-    def extend_architectures(sources_dir: Path, architecture: str) -> None:
+    def extend_architectures(sources_dir: Path, architecture: str) -> List[PkgbuildPatch]:
         """
         extend existing PKGBUILD with repository architecture
 
         Args:
             sources_dir(Path): local path to directory with source files
             architecture(str): repository architecture
-        """
-        pkgbuild_path = sources_dir / "PKGBUILD"
-        if not pkgbuild_path.is_file():
-            return
 
+        Returns:
+            List[PkgbuildPatch]: generated patch for PKGBUILD architectures if required
+        """
         architectures = Package.supported_architectures(sources_dir)
         if "any" in architectures:  # makepkg does not like when there is any other arch except for any
-            return
+            return []
         architectures.add(architecture)
-        patch = PkgbuildPatch("arch", list(architectures))
-        patch.write(pkgbuild_path)
+        return [PkgbuildPatch("arch", list(architectures))]
 
     @staticmethod
     def fetch(sources_dir: Path, remote: Optional[RemoteSource]) -> None:
@@ -134,14 +132,14 @@ class Sources(LazyLogging):
                               exception=None, cwd=sources_dir, logger=instance.logger)
 
     @staticmethod
-    def load(sources_dir: Path, package: Package, patch: Optional[str], paths: RepositoryPaths) -> None:
+    def load(sources_dir: Path, package: Package, patches: List[PkgbuildPatch], paths: RepositoryPaths) -> None:
         """
         fetch sources from remote and apply patches
 
         Args:
             sources_dir(Path): local path to fetch
             package(Package): package definitions
-            patch(Optional[str]): optional patch to be applied
+            patches(List[PkgbuildPatch]): optional patch to be applied
             paths(RepositoryPaths): repository paths instance
         """
         instance = Sources()
@@ -150,9 +148,9 @@ class Sources(LazyLogging):
             shutil.copytree(cache_dir, sources_dir, dirs_exist_ok=True)
         instance.fetch(sources_dir, package.remote)
 
-        if patch is not None:
+        patches.extend(instance.extend_architectures(sources_dir, paths.architecture))
+        for patch in patches:
             instance.patch_apply(sources_dir, patch)
-        instance.extend_architectures(sources_dir, paths.architecture)
 
     @staticmethod
     def patch_create(sources_dir: Path, *pattern: str) -> str:
@@ -248,15 +246,18 @@ class Sources(LazyLogging):
             dst = sources_dir / src.relative_to(pkgbuild_dir)
             shutil.move(src, dst)
 
-    def patch_apply(self, sources_dir: Path, patch: str) -> None:
+    def patch_apply(self, sources_dir: Path, patch: PkgbuildPatch) -> None:
         """
         apply patches if any
 
         Args:
             sources_dir(Path): local path to directory with git sources
-            patch(str): patch to be applied
+            patch(PkgbuildPatch): patch to be applied
         """
         # create patch
-        self.logger.info("apply patch from database")
-        Sources._check_output("git", "apply", "--ignore-space-change", "--ignore-whitespace",
-                              exception=None, cwd=sources_dir, input_data=patch, logger=self.logger)
+        self.logger.info("apply patch %s from database at %s", patch.key, sources_dir)
+        if patch.is_plain_diff:
+            Sources._check_output("git", "apply", "--ignore-space-change", "--ignore-whitespace",
+                                  exception=None, cwd=sources_dir, input_data=patch.serialize(), logger=self.logger)
+        else:
+            patch.write(sources_dir / "PKGBUILD")
diff --git a/src/ahriman/core/database/migrations/m003_patch_variables.py b/src/ahriman/core/database/migrations/m003_patch_variables.py
new file mode 100644
index 00000000..b454bd85
--- /dev/null
+++ b/src/ahriman/core/database/migrations/m003_patch_variables.py
@@ -0,0 +1,43 @@
+#
+# Copyright (c) 2021-2022 ahriman team.
+#
+# This file is part of ahriman
+# (see https://github.com/arcan1s/ahriman).
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+__all__ = ["steps"]
+
+
+steps = [
+    """
+    alter table patches rename to patches_
+    """,
+    """
+    create table patches (
+        package_base text not null,
+        variable text,
+        patch blob not null
+    )
+    """,
+    """
+    create unique index patches_package_base_variable on patches (package_base, coalesce(variable, ''))
+    """,
+    """
+    insert into patches (package_base, patch) select package_base, patch from patches_
+    """,
+    """
+    drop table patches_
+    """,
+]
diff --git a/src/ahriman/core/database/operations/patch_operations.py b/src/ahriman/core/database/operations/patch_operations.py
index 9dcebfe4..97b483d5 100644
--- a/src/ahriman/core/database/operations/patch_operations.py
+++ b/src/ahriman/core/database/operations/patch_operations.py
@@ -17,10 +17,13 @@
 # You should have received a copy of the GNU General Public License
 # along with this program. If not, see <http://www.gnu.org/licenses/>.
 #
+from collections import defaultdict
+
 from sqlite3 import Connection
-from typing import Dict, Optional
+from typing import Dict, List, Optional, Tuple
 
 from ahriman.core.database.operations import Operations
+from ahriman.models.pkgbuild_patch import PkgbuildPatch
 
 
 class PatchOperations(Operations):
@@ -28,7 +31,7 @@ class PatchOperations(Operations):
     operations for patches
     """
 
-    def patches_get(self, package_base: str) -> Optional[str]:
+    def patches_get(self, package_base: str) -> List[PkgbuildPatch]:
         """
         retrieve patches for the package
 
@@ -36,62 +39,77 @@ class PatchOperations(Operations):
             package_base(str): package base to search for patches
 
         Returns:
-            Optional[str]: plain text patch for the package
+            List[PkgbuildPatch]: plain text patch for the package
         """
-        return self.patches_list(package_base).get(package_base)
+        return self.patches_list(package_base, []).get(package_base, [])
 
-    def patches_insert(self, package_base: str, patch: str) -> None:
+    def patches_insert(self, package_base: str, patch: PkgbuildPatch) -> None:
         """
         insert or update patch in database
 
         Args:
             package_base(str): package base to insert
-            patch(str): patch content
+            patch(PkgbuildPatch): patch content
         """
         def run(connection: Connection) -> None:
             connection.execute(
                 """
                 insert into patches
-                (package_base, patch)
+                (package_base, variable, patch)
                 values
-                (:package_base, :patch)
-                on conflict (package_base) do update set
+                (:package_base, :variable, :patch)
+                on conflict (package_base, coalesce(variable, '')) do update set
                 patch = :patch
                 """,
-                {"package_base": package_base, "patch": patch})
+                {"package_base": package_base, "variable": patch.key, "patch": patch.value})
 
         return self.with_connection(run, commit=True)
 
-    def patches_list(self, package_base: Optional[str]) -> Dict[str, str]:
+    def patches_list(self, package_base: Optional[str], variables: List[str]) -> Dict[str, List[PkgbuildPatch]]:
         """
         extract all patches
 
         Args:
             package_base(Optional[str]): optional filter by package base
+            variables(List[str]): extract patches only for specified PKGBUILD variables
 
         Returns:
-            Dict[str, str]: map of package base to patch content
+            Dict[str, List[PkgbuildPatch]]: map of package base to patch content
         """
-        def run(connection: Connection) -> Dict[str, str]:
-            return {
-                cursor["package_base"]: cursor["patch"]
+        def run(connection: Connection) -> List[Tuple[str, PkgbuildPatch]]:
+            return [
+                (cursor["package_base"], PkgbuildPatch(cursor["variable"], cursor["patch"]))
                 for cursor in connection.execute(
                     """select * from patches where :package_base is null or package_base = :package_base""",
                     {"package_base": package_base})
-            }
+            ]
 
-        return self.with_connection(run)
+        # we could use itertools & operator but why?
+        patches: Dict[str, List[PkgbuildPatch]] = defaultdict(list)
+        for package, patch in self.with_connection(run):
+            if variables and patch.key not in variables:
+                continue
+            patches[package].append(patch)
+        return dict(patches)
 
-    def patches_remove(self, package_base: str) -> None:
+    def patches_remove(self, package_base: str, variables: List[str]) -> None:
         """
         remove patch set
 
         Args:
             package_base(str): package base to clear patches
+            variables(List[str]): remove patches only for specified PKGBUILD variables
         """
+        def run_many(connection: Connection) -> None:
+            connection.executemany(
+                """delete from patches where package_base = :package_base and variable = :variable""",
+                [{"package_base": package_base, "variable": variable} for variable in variables])
+
         def run(connection: Connection) -> None:
             connection.execute(
                 """delete from patches where package_base = :package_base""",
                 {"package_base": package_base})
 
+        if variables:
+            return self.with_connection(run_many, commit=True)
         return self.with_connection(run, commit=True)
diff --git a/src/ahriman/core/formatters/__init__.py b/src/ahriman/core/formatters/__init__.py
index 931e99d5..c6cffb1c 100644
--- a/src/ahriman/core/formatters/__init__.py
+++ b/src/ahriman/core/formatters/__init__.py
@@ -24,6 +24,7 @@ from ahriman.core.formatters.aur_printer import AurPrinter
 from ahriman.core.formatters.build_printer import BuildPrinter
 from ahriman.core.formatters.configuration_printer import ConfigurationPrinter
 from ahriman.core.formatters.package_printer import PackagePrinter
+from ahriman.core.formatters.patch_printer import PatchPrinter
 from ahriman.core.formatters.status_printer import StatusPrinter
 from ahriman.core.formatters.update_printer import UpdatePrinter
 from ahriman.core.formatters.user_printer import UserPrinter
diff --git a/src/ahriman/core/formatters/patch_printer.py b/src/ahriman/core/formatters/patch_printer.py
new file mode 100644
index 00000000..ab9568d6
--- /dev/null
+++ b/src/ahriman/core/formatters/patch_printer.py
@@ -0,0 +1,56 @@
+#
+# Copyright (c) 2021-2022 ahriman team.
+#
+# This file is part of ahriman
+# (see https://github.com/arcan1s/ahriman).
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+from typing import List
+
+from ahriman.core.formatters import StringPrinter
+from ahriman.models.pkgbuild_patch import PkgbuildPatch
+from ahriman.models.property import Property
+
+
+class PatchPrinter(StringPrinter):
+    """
+    print content of the PKGBUILD patch
+
+    Attributes:
+        patches(List[PkgbuildPatch]): PKGBUILD patch object
+    """
+
+    def __init__(self, package_base: str, patches: List[PkgbuildPatch]) -> None:
+        """
+        default constructor
+
+        Args:
+            package_base(str): package base
+            patches(List[PkgbuildPatch]): PKGBUILD patch object
+        """
+        StringPrinter.__init__(self, package_base)
+        self.patches = patches
+
+    def properties(self) -> List[Property]:
+        """
+        convert content into printable data
+
+        Returns:
+            List[Property]: list of content properties
+        """
+        return [
+            Property(patch.key or "Full source diff", patch.value, is_required=True)
+            for patch in self.patches
+        ]
diff --git a/src/ahriman/core/repository/executor.py b/src/ahriman/core/repository/executor.py
index 46f847ea..48ed817f 100644
--- a/src/ahriman/core/repository/executor.py
+++ b/src/ahriman/core/repository/executor.py
@@ -109,7 +109,7 @@ class Executor(Cleaner):
             try:
                 self.paths.tree_clear(package_base)  # remove all internal files
                 self.database.build_queue_clear(package_base)
-                self.database.patches_remove(package_base)
+                self.database.patches_remove(package_base, [])
                 self.reporter.remove(package_base)  # we only update status page in case of base removal
             except Exception:
                 self.logger.exception("could not remove base %s", package_base)
diff --git a/src/ahriman/models/package.py b/src/ahriman/models/package.py
index 96183717..447a8e5c 100644
--- a/src/ahriman/models/package.py
+++ b/src/ahriman/models/package.py
@@ -305,7 +305,7 @@ class Package(LazyLogging):
 
         from ahriman.core.build_tools.sources import Sources
 
-        Sources.load(paths.cache_for(self.base), self, None, paths)
+        Sources.load(paths.cache_for(self.base), self, [], paths)
 
         try:
             # update pkgver first
diff --git a/src/ahriman/models/pkgbuild_patch.py b/src/ahriman/models/pkgbuild_patch.py
index 64c7a5dc..ca6a4b7e 100644
--- a/src/ahriman/models/pkgbuild_patch.py
+++ b/src/ahriman/models/pkgbuild_patch.py
@@ -21,7 +21,7 @@ import shlex
 
 from dataclasses import dataclass, field
 from pathlib import Path
-from typing import List, Union
+from typing import List, Optional, Union
 
 
 @dataclass(frozen=True)
@@ -30,16 +30,23 @@ class PkgbuildPatch:
     wrapper for patching PKBGUILDs
 
     Attributes:
-        key(str): name of the property in PKGBUILD, e.g. version, url etc
+        key(Optional[str]): name of the property in PKGBUILD, e.g. version, url etc. If not set, patch will be
+            considered as full PKGBUILD diffs
         value(Union[str, List[str]]): value of the stored PKGBUILD property. It must be either string or list of string
             values
         unsafe(bool): if set, value will be not quoted, might break PKGBUILD
     """
 
-    key: str
+    key: Optional[str]
     value: Union[str, List[str]]
     unsafe: bool = field(default=False, kw_only=True)
 
+    def __post_init__(self) -> None:
+        """
+        remove empty key
+        """
+        object.__setattr__(self, "key", self.key or None)
+
     @property
     def is_function(self) -> bool:
         """
@@ -48,7 +55,17 @@ class PkgbuildPatch:
         Returns:
             bool: True in case if key ends with parentheses and False otherwise
         """
-        return self.key.endswith("()")
+        return self.key is not None and self.key.endswith("()")
+
+    @property
+    def is_plain_diff(self) -> bool:
+        """
+        check if patch is full diff one or just single-variable patch
+
+        Returns:
+            bool: True in case key set and False otherwise
+        """
+        return self.key is None
 
     def quote(self, value: str) -> str:
         """
@@ -74,6 +91,8 @@ class PkgbuildPatch:
         if isinstance(self.value, list):  # list like
             value = " ".join(map(self.quote, self.value))
             return f"""{self.key}=({value})"""
+        if self.is_plain_diff:  # no additional logic for plain diffs
+            return self.value
         # we suppose that function values are only supported in string-like values
         if self.is_function:
             return f"{self.key} {self.value}"  # no quoting enabled here
diff --git a/tests/ahriman/application/handlers/test_handler_patch.py b/tests/ahriman/application/handlers/test_handler_patch.py
index 3960aeed..71d8aae3 100644
--- a/tests/ahriman/application/handlers/test_handler_patch.py
+++ b/tests/ahriman/application/handlers/test_handler_patch.py
@@ -1,5 +1,6 @@
 import argparse
 import pytest
+import sys
 
 from pathlib import Path
 from pytest_mock import MockerFixture
@@ -9,6 +10,7 @@ from ahriman.application.handlers import Patch
 from ahriman.core.configuration import Configuration
 from ahriman.models.action import Action
 from ahriman.models.package import Package
+from ahriman.models.pkgbuild_patch import PkgbuildPatch
 
 
 def _default_args(args: argparse.Namespace) -> argparse.Namespace:
@@ -25,6 +27,7 @@ def _default_args(args: argparse.Namespace) -> argparse.Namespace:
     args.exit_code = False
     args.remove = False
     args.track = ["*.diff", "*.patch"]
+    args.variable = None
     return args
 
 
@@ -35,12 +38,31 @@ def test_run(args: argparse.Namespace, configuration: Configuration, mocker: Moc
     args = _default_args(args)
     args.action = Action.Update
     mocker.patch("ahriman.models.repository_paths.RepositoryPaths.tree_create")
+    patch_mock = mocker.patch("ahriman.application.handlers.Patch.patch_create_from_diff",
+                              return_value=(args.package, PkgbuildPatch(None, "patch")))
     application_mock = mocker.patch("ahriman.application.handlers.Patch.patch_set_create")
-    on_start_mock = mocker.patch("ahriman.application.application.Application.on_start")
 
     Patch.run(args, "x86_64", configuration, True, False)
-    application_mock.assert_called_once_with(pytest.helpers.anyvar(int), Path(args.package), args.track)
-    on_start_mock.assert_called_once_with()
+    patch_mock.assert_called_once_with(args.package, args.track)
+    application_mock.assert_called_once_with(pytest.helpers.anyvar(int), args.package, PkgbuildPatch(None, "patch"))
+
+
+def test_run_function(args: argparse.Namespace, configuration: Configuration, mocker: MockerFixture) -> None:
+    """
+    must run command with patch function flag
+    """
+    args = _default_args(args)
+    args.action = Action.Update
+    args.patch = "patch"
+    args.variable = "version"
+    patch = PkgbuildPatch(args.variable, args.patch)
+    mocker.patch("ahriman.models.repository_paths.RepositoryPaths.tree_create")
+    patch_mock = mocker.patch("ahriman.application.handlers.Patch.patch_create_from_function", return_value=patch)
+    application_mock = mocker.patch("ahriman.application.handlers.Patch.patch_set_create")
+
+    Patch.run(args, "x86_64", configuration, True, False)
+    patch_mock.assert_called_once_with(args.variable, args.patch)
+    application_mock.assert_called_once_with(pytest.helpers.anyvar(int), args.package, patch)
 
 
 def test_run_list(args: argparse.Namespace, configuration: Configuration, mocker: MockerFixture) -> None:
@@ -49,11 +71,12 @@ def test_run_list(args: argparse.Namespace, configuration: Configuration, mocker
     """
     args = _default_args(args)
     args.action = Action.List
+    args.variable = ["version"]
     mocker.patch("ahriman.models.repository_paths.RepositoryPaths.tree_create")
     application_mock = mocker.patch("ahriman.application.handlers.Patch.patch_set_list")
 
     Patch.run(args, "x86_64", configuration, True, False)
-    application_mock.assert_called_once_with(pytest.helpers.anyvar(int), args.package, False)
+    application_mock.assert_called_once_with(pytest.helpers.anyvar(int), args.package, ["version"], False)
 
 
 def test_run_remove(args: argparse.Namespace, configuration: Configuration, mocker: MockerFixture) -> None:
@@ -62,24 +85,71 @@ def test_run_remove(args: argparse.Namespace, configuration: Configuration, mock
     """
     args = _default_args(args)
     args.action = Action.Remove
+    args.variable = ["version"]
     mocker.patch("ahriman.models.repository_paths.RepositoryPaths.tree_create")
     application_mock = mocker.patch("ahriman.application.handlers.Patch.patch_set_remove")
 
     Patch.run(args, "x86_64", configuration, True, False)
-    application_mock.assert_called_once_with(pytest.helpers.anyvar(int), args.package)
+    application_mock.assert_called_once_with(pytest.helpers.anyvar(int), args.package, ["version"])
+
+
+def test_patch_create_from_diff(package_ahriman: Package, mocker: MockerFixture) -> None:
+    """
+    must create patch from directory tree diff
+    """
+    patch = PkgbuildPatch(None, "patch")
+    path = Path("local")
+    mocker.patch("pathlib.Path.mkdir")
+    package_mock = mocker.patch("ahriman.models.package.Package.from_build", return_value=package_ahriman)
+    sources_mock = mocker.patch("ahriman.core.build_tools.sources.Sources.patch_create", return_value=patch.value)
+
+    assert Patch.patch_create_from_diff(path, ["*.diff"]) == (package_ahriman.base, patch)
+    package_mock.assert_called_once_with(path)
+    sources_mock.assert_called_once_with(path, "*.diff")
+
+
+def test_patch_create_from_function(mocker: MockerFixture) -> None:
+    """
+    must create function patch from file
+    """
+    path = Path("local")
+    patch = PkgbuildPatch("version", "patch")
+    read_mock = mocker.patch("pathlib.Path.read_text", return_value=patch.value)
+
+    assert Patch.patch_create_from_function(patch.key, path) == patch
+    read_mock.assert_called_once_with(encoding="utf8")
+
+
+def test_patch_create_from_function_stdin(mocker: MockerFixture) -> None:
+    """
+    must create function patch from stdin
+    """
+    patch = PkgbuildPatch("version", "This is a patch")
+    mocker.patch.object(sys, "stdin", patch.value.splitlines())
+    assert Patch.patch_create_from_function(patch.key, None) == patch
+
+
+def test_patch_create_from_function_strip(mocker: MockerFixture) -> None:
+    """
+    must remove spaces at the beginning and at the end of the line
+    """
+    patch = PkgbuildPatch("version", "This is a patch")
+    mocker.patch.object(sys, "stdin", ["\n"] + patch.value.splitlines() + ["\n"])
+    assert Patch.patch_create_from_function(patch.key, None) == patch
 
 
 def test_patch_set_list(application: Application, mocker: MockerFixture) -> None:
     """
     must list available patches for the command
     """
-    get_mock = mocker.patch("ahriman.core.database.SQLite.patches_list", return_value={"ahriman": "patch"})
+    get_mock = mocker.patch("ahriman.core.database.SQLite.patches_list",
+                            return_value={"ahriman": PkgbuildPatch(None, "patch")})
     print_mock = mocker.patch("ahriman.core.formatters.Printer.print")
     check_mock = mocker.patch("ahriman.application.handlers.Handler.check_if_empty")
 
-    Patch.patch_set_list(application, "ahriman", False)
-    get_mock.assert_called_once_with("ahriman")
-    print_mock.assert_called_once_with(verbose=True)
+    Patch.patch_set_list(application, "ahriman", ["version"], False)
+    get_mock.assert_called_once_with("ahriman", ["version"])
+    print_mock.assert_called_once_with(verbose=True, separator=" = ")
     check_mock.assert_called_once_with(False, False)
 
 
@@ -90,7 +160,7 @@ def test_patch_set_list_empty_exception(application: Application, mocker: Mocker
     mocker.patch("ahriman.core.database.SQLite.patches_list", return_value={})
     check_mock = mocker.patch("ahriman.application.handlers.Handler.check_if_empty")
 
-    Patch.patch_set_list(application, "ahriman", True)
+    Patch.patch_set_list(application, "ahriman", [], True)
     check_mock.assert_called_once_with(True, True)
 
 
@@ -98,13 +168,9 @@ def test_patch_set_create(application: Application, package_ahriman: Package, mo
     """
     must create patch set for the package
     """
-    mocker.patch("pathlib.Path.mkdir")
-    mocker.patch("ahriman.models.package.Package.from_build", return_value=package_ahriman)
-    mocker.patch("ahriman.core.build_tools.sources.Sources.patch_create", return_value="patch")
     create_mock = mocker.patch("ahriman.core.database.SQLite.patches_insert")
-
-    Patch.patch_set_create(application, Path("path"), ["*.patch"])
-    create_mock.assert_called_once_with(package_ahriman.base, "patch")
+    Patch.patch_set_create(application, package_ahriman.base, PkgbuildPatch("version", package_ahriman.version))
+    create_mock.assert_called_once_with(package_ahriman.base, PkgbuildPatch("version", package_ahriman.version))
 
 
 def test_patch_set_remove(application: Application, package_ahriman: Package, mocker: MockerFixture) -> None:
@@ -112,5 +178,5 @@ def test_patch_set_remove(application: Application, package_ahriman: Package, mo
     must remove patch set for the package
     """
     remove_mock = mocker.patch("ahriman.core.database.SQLite.patches_remove")
-    Patch.patch_set_remove(application, package_ahriman.base)
-    remove_mock.assert_called_once_with(package_ahriman.base)
+    Patch.patch_set_remove(application, package_ahriman.base, ["version"])
+    remove_mock.assert_called_once_with(package_ahriman.base, ["version"])
diff --git a/tests/ahriman/application/test_ahriman.py b/tests/ahriman/application/test_ahriman.py
index 8d04c14e..e2d607bd 100644
--- a/tests/ahriman/application/test_ahriman.py
+++ b/tests/ahriman/application/test_ahriman.py
@@ -197,7 +197,7 @@ def test_subparsers_patch_add(parser: argparse.ArgumentParser) -> None:
     """
     patch-add command must imply action, architecture list, lock and no-report
     """
-    args = parser.parse_args(["patch-add", "ahriman"])
+    args = parser.parse_args(["patch-add", "ahriman", "version"])
     assert args.action == Action.Update
     assert args.architecture == [""]
     assert args.lock is None
@@ -208,18 +208,10 @@ def test_subparsers_patch_add_architecture(parser: argparse.ArgumentParser) -> N
     """
     patch-add command must correctly parse architecture list
     """
-    args = parser.parse_args(["-a", "x86_64", "patch-add", "ahriman"])
+    args = parser.parse_args(["-a", "x86_64", "patch-add", "ahriman", "version"])
     assert args.architecture == [""]
 
 
-def test_subparsers_patch_add_track(parser: argparse.ArgumentParser) -> None:
-    """
-    patch-add command must correctly parse track files patterns
-    """
-    args = parser.parse_args(["patch-add", "-t", "*.py", "ahriman"])
-    assert args.track == ["*.diff", "*.patch", "*.py"]
-
-
 def test_subparsers_patch_list(parser: argparse.ArgumentParser) -> None:
     """
     patch-list command must imply action, architecture list, lock and no-report
@@ -258,6 +250,42 @@ def test_subparsers_patch_remove_architecture(parser: argparse.ArgumentParser) -
     assert args.architecture == [""]
 
 
+def test_subparsers_patch_set_add(parser: argparse.ArgumentParser) -> None:
+    """
+    patch-set-add command must imply action, architecture list, lock, no-report and variable
+    """
+    args = parser.parse_args(["patch-set-add", "ahriman"])
+    assert args.action == Action.Update
+    assert args.architecture == [""]
+    assert args.lock is None
+    assert args.no_report
+    assert args.variable is None
+
+
+def test_subparsers_patch_set_add_architecture(parser: argparse.ArgumentParser) -> None:
+    """
+    patch-set-add command must correctly parse architecture list
+    """
+    args = parser.parse_args(["-a", "x86_64", "patch-set-add", "ahriman"])
+    assert args.architecture == [""]
+
+
+def test_subparsers_patch_set_add_option_package(parser: argparse.ArgumentParser) -> None:
+    """
+    patch-set-add command must convert package option to path instance
+    """
+    args = parser.parse_args(["patch-set-add", "ahriman"])
+    assert isinstance(args.package, Path)
+
+
+def test_subparsers_patch_set_add_option_track(parser: argparse.ArgumentParser) -> None:
+    """
+    patch-set-add command must correctly parse track files patterns
+    """
+    args = parser.parse_args(["patch-set-add", "-t", "*.py", "ahriman"])
+    assert args.track == ["*.diff", "*.patch", "*.py"]
+
+
 def test_subparsers_repo_backup(parser: argparse.ArgumentParser) -> None:
     """
     repo-backup command must imply architecture list, lock, no-report and unsafe
diff --git a/tests/ahriman/core/build_tools/test_sources.py b/tests/ahriman/core/build_tools/test_sources.py
index 8499405f..a78b82f6 100644
--- a/tests/ahriman/core/build_tools/test_sources.py
+++ b/tests/ahriman/core/build_tools/test_sources.py
@@ -6,6 +6,7 @@ from unittest import mock
 
 from ahriman.core.build_tools.sources import Sources
 from ahriman.models.package import Package
+from ahriman.models.pkgbuild_patch import PkgbuildPatch
 from ahriman.models.remote_source import RemoteSource
 from ahriman.models.repository_paths import RepositoryPaths
 
@@ -16,11 +17,9 @@ def test_extend_architectures(mocker: MockerFixture) -> None:
     """
     mocker.patch("pathlib.Path.is_file", return_value=True)
     archs_mock = mocker.patch("ahriman.models.package.Package.supported_architectures", return_value={"x86_64"})
-    write_mock = mocker.patch("ahriman.models.pkgbuild_patch.PkgbuildPatch.write")
 
-    Sources.extend_architectures(Path("local"), "i686")
+    assert Sources.extend_architectures(Path("local"), "i686") == [PkgbuildPatch("arch", list({"x86_64", "i686"}))]
     archs_mock.assert_called_once_with(Path("local"))
-    write_mock.assert_called_once_with(Path("local") / "PKGBUILD")
 
 
 def test_extend_architectures_any(mocker: MockerFixture) -> None:
@@ -29,21 +28,7 @@ def test_extend_architectures_any(mocker: MockerFixture) -> None:
     """
     mocker.patch("pathlib.Path.is_file", return_value=True)
     mocker.patch("ahriman.models.package.Package.supported_architectures", return_value={"any"})
-    write_mock = mocker.patch("ahriman.models.pkgbuild_patch.PkgbuildPatch.write")
-
-    Sources.extend_architectures(Path("local"), "i686")
-    write_mock.assert_not_called()
-
-
-def test_extend_architectures_skip(mocker: MockerFixture) -> None:
-    """
-    must skip extending list of the architectures in case if no PKGBUILD file found
-    """
-    mocker.patch("pathlib.Path.is_file", return_value=False)
-    write_mock = mocker.patch("ahriman.models.pkgbuild_patch.PkgbuildPatch.write")
-
-    Sources.extend_architectures(Path("local"), "i686")
-    write_mock.assert_not_called()
+    assert Sources.extend_architectures(Path("local"), "i686") == []
 
 
 def test_fetch_empty(remote_source: RemoteSource, mocker: MockerFixture) -> None:
@@ -167,15 +152,16 @@ def test_load(package_ahriman: Package, repository_paths: RepositoryPaths, mocke
     """
     must load packages sources correctly
     """
-    mocker.patch("pathlib.Path.is_dir", return_value=False)
+    patch = PkgbuildPatch(None, "patch")
+    path = Path("local")
     fetch_mock = mocker.patch("ahriman.core.build_tools.sources.Sources.fetch")
     patch_mock = mocker.patch("ahriman.core.build_tools.sources.Sources.patch_apply")
-    architectures_mock = mocker.patch("ahriman.core.build_tools.sources.Sources.extend_architectures")
+    architectures_mock = mocker.patch("ahriman.core.build_tools.sources.Sources.extend_architectures", return_value=[])
 
-    Sources.load(Path("local"), package_ahriman, "patch", repository_paths)
-    fetch_mock.assert_called_once_with(Path("local"), package_ahriman.remote)
-    patch_mock.assert_called_once_with(Path("local"), "patch")
-    architectures_mock.assert_called_once_with(Path("local"), repository_paths.architecture)
+    Sources.load(path, package_ahriman, [patch], repository_paths)
+    fetch_mock.assert_called_once_with(path, package_ahriman.remote)
+    patch_mock.assert_called_once_with(path, patch)
+    architectures_mock.assert_called_once_with(path, repository_paths.architecture)
 
 
 def test_load_no_patch(package_ahriman: Package, repository_paths: RepositoryPaths, mocker: MockerFixture) -> None:
@@ -184,9 +170,10 @@ def test_load_no_patch(package_ahriman: Package, repository_paths: RepositoryPat
     """
     mocker.patch("pathlib.Path.is_dir", return_value=False)
     mocker.patch("ahriman.core.build_tools.sources.Sources.fetch")
+    mocker.patch("ahriman.core.build_tools.sources.Sources.extend_architectures", return_value=[])
     patch_mock = mocker.patch("ahriman.core.build_tools.sources.Sources.patch_apply")
 
-    Sources.load(Path("local"), package_ahriman, None, repository_paths)
+    Sources.load(Path("local"), package_ahriman, [], repository_paths)
     patch_mock.assert_not_called()
 
 
@@ -197,8 +184,9 @@ def test_load_with_cache(package_ahriman: Package, repository_paths: RepositoryP
     mocker.patch("pathlib.Path.is_dir", return_value=True)
     copytree_mock = mocker.patch("shutil.copytree")
     mocker.patch("ahriman.core.build_tools.sources.Sources.fetch")
+    mocker.patch("ahriman.core.build_tools.sources.Sources.extend_architectures", return_value=[])
 
-    Sources.load(Path("local"), package_ahriman, None, repository_paths)
+    Sources.load(Path("local"), package_ahriman, [], repository_paths)
     copytree_mock.assert_called_once()  # we do not check full command here, sorry
 
 
@@ -331,11 +319,24 @@ def test_patch_apply(sources: Sources, mocker: MockerFixture) -> None:
     """
     must apply patches if any
     """
+    patch = PkgbuildPatch(None, "patch")
     check_output_mock = mocker.patch("ahriman.core.build_tools.sources.Sources._check_output")
 
     local = Path("local")
-    sources.patch_apply(local, "patches")
+    sources.patch_apply(local, patch)
     check_output_mock.assert_called_once_with(
         "git", "apply", "--ignore-space-change", "--ignore-whitespace",
-        exception=None, cwd=local, input_data="patches", logger=pytest.helpers.anyvar(int)
+        exception=None, cwd=local, input_data=patch.value, logger=pytest.helpers.anyvar(int)
     )
+
+
+def test_patch_apply_function(sources: Sources, mocker: MockerFixture) -> None:
+    """
+    must apply single-function patches
+    """
+    patch = PkgbuildPatch("version", "42")
+    local = Path("local")
+    write_mock = mocker.patch("ahriman.models.pkgbuild_patch.PkgbuildPatch.write")
+
+    sources.patch_apply(local, patch)
+    write_mock.assert_called_once_with(local / "PKGBUILD")
diff --git a/tests/ahriman/core/build_tools/test_task.py b/tests/ahriman/core/build_tools/test_task.py
index 11652bb7..44b5669b 100644
--- a/tests/ahriman/core/build_tools/test_task.py
+++ b/tests/ahriman/core/build_tools/test_task.py
@@ -20,4 +20,4 @@ def test_init(task_ahriman: Task, database: SQLite, mocker: MockerFixture) -> No
     """
     load_mock = mocker.patch("ahriman.core.build_tools.sources.Sources.load")
     task_ahriman.init(Path("ahriman"), database)
-    load_mock.assert_called_once_with(Path("ahriman"), task_ahriman.package, None, task_ahriman.paths)
+    load_mock.assert_called_once_with(Path("ahriman"), task_ahriman.package, [], task_ahriman.paths)
diff --git a/tests/ahriman/core/database/migrations/test_m003_patch_variables.py b/tests/ahriman/core/database/migrations/test_m003_patch_variables.py
new file mode 100644
index 00000000..f03b786c
--- /dev/null
+++ b/tests/ahriman/core/database/migrations/test_m003_patch_variables.py
@@ -0,0 +1,8 @@
+from ahriman.core.database.migrations.m003_patch_variables import steps
+
+
+def test_migration_package_source() -> None:
+    """
+    migration must not be empty
+    """
+    assert steps
diff --git a/tests/ahriman/core/database/operations/test_patch_operations.py b/tests/ahriman/core/database/operations/test_patch_operations.py
index adc14e3e..4c13e862 100644
--- a/tests/ahriman/core/database/operations/test_patch_operations.py
+++ b/tests/ahriman/core/database/operations/test_patch_operations.py
@@ -1,55 +1,96 @@
 from ahriman.core.database import SQLite
 from ahriman.models.package import Package
+from ahriman.models.pkgbuild_patch import PkgbuildPatch
 
 
 def test_patches_get_insert(database: SQLite, package_ahriman: Package, package_python_schedule: Package) -> None:
     """
     must insert patch to database
     """
-    database.patches_insert(package_ahriman.base, "patch_1")
-    database.patches_insert(package_python_schedule.base, "patch_2")
-    assert database.patches_get(package_ahriman.base) == "patch_1"
-    assert not database.build_queue_get()
+    database.patches_insert(package_ahriman.base, PkgbuildPatch(None, "patch_1"))
+    database.patches_insert(package_ahriman.base, PkgbuildPatch("key", "patch_3"))
+    database.patches_insert(package_python_schedule.base, PkgbuildPatch(None, "patch_2"))
+    assert database.patches_get(package_ahriman.base) == [
+        PkgbuildPatch(None, "patch_1"), PkgbuildPatch("key", "patch_3")
+    ]
 
 
 def test_patches_list(database: SQLite, package_ahriman: Package, package_python_schedule: Package) -> None:
     """
     must list all patches
     """
-    database.patches_insert(package_ahriman.base, "patch1")
-    database.patches_insert(package_python_schedule.base, "patch2")
-    assert database.patches_list(None) == {package_ahriman.base: "patch1", package_python_schedule.base: "patch2"}
+    database.patches_insert(package_ahriman.base, PkgbuildPatch(None, "patch1"))
+    database.patches_insert(package_ahriman.base, PkgbuildPatch("key", "patch3"))
+    database.patches_insert(package_python_schedule.base, PkgbuildPatch(None, "patch2"))
+    assert database.patches_list(None, []) == {
+        package_ahriman.base: [PkgbuildPatch(None, "patch1"), PkgbuildPatch("key", "patch3")],
+        package_python_schedule.base: [PkgbuildPatch(None, "patch2")],
+    }
 
 
 def test_patches_list_filter(database: SQLite, package_ahriman: Package, package_python_schedule: Package) -> None:
     """
     must list all patches filtered by package name (same as get)
     """
-    database.patches_insert(package_ahriman.base, "patch1")
-    database.patches_insert(package_python_schedule.base, "patch2")
+    database.patches_insert(package_ahriman.base, PkgbuildPatch(None, "patch1"))
+    database.patches_insert(package_python_schedule.base, PkgbuildPatch(None, "patch2"))
 
-    assert database.patches_list(package_ahriman.base) == {package_ahriman.base: "patch1"}
-    assert database.patches_list(package_python_schedule.base) == {package_python_schedule.base: "patch2"}
+    assert database.patches_list(package_ahriman.base, []) == {package_ahriman.base: [PkgbuildPatch(None, "patch1")]}
+    assert database.patches_list(package_python_schedule.base, []) == {
+        package_python_schedule.base: [PkgbuildPatch(None, "patch2")],
+    }
+
+
+def test_patches_list_filter_by_variable(database: SQLite, package_ahriman: Package,
+                                         package_python_schedule: Package) -> None:
+    """
+    must list all patches filtered by package name (same as get)
+    """
+    database.patches_insert(package_ahriman.base, PkgbuildPatch(None, "patch1"))
+    database.patches_insert(package_ahriman.base, PkgbuildPatch("key", "patch2"))
+    database.patches_insert(package_python_schedule.base, PkgbuildPatch(None, "patch3"))
+
+    assert database.patches_list(None, []) == {
+        package_ahriman.base: [PkgbuildPatch(None, "patch1"), PkgbuildPatch("key", "patch2")],
+        package_python_schedule.base: [PkgbuildPatch(None, "patch3")],
+    }
+    assert database.patches_list(None, ["key"]) == {
+        package_ahriman.base: [PkgbuildPatch("key", "patch2")],
+    }
 
 
 def test_patches_insert_remove(database: SQLite, package_ahriman: Package, package_python_schedule: Package) -> None:
     """
     must remove patch from database
     """
-    database.patches_insert(package_ahriman.base, "patch_1")
-    database.patches_insert(package_python_schedule.base, "patch_2")
-    database.patches_remove(package_ahriman.base)
+    database.patches_insert(package_ahriman.base, PkgbuildPatch(None, "patch1"))
+    database.patches_insert(package_python_schedule.base, PkgbuildPatch(None, "patch2"))
+    database.patches_remove(package_ahriman.base, [])
 
-    assert database.patches_get(package_ahriman.base) is None
-    database.patches_insert(package_python_schedule.base, "patch_2")
+    assert database.patches_get(package_ahriman.base) == []
+    assert database.patches_get(package_python_schedule.base) == [PkgbuildPatch(None, "patch2")]
+
+
+def test_patches_insert_remove_by_variable(database: SQLite, package_ahriman: Package,
+                                           package_python_schedule: Package) -> None:
+    """
+    must remove patch from database by variable
+    """
+    database.patches_insert(package_ahriman.base, PkgbuildPatch(None, "patch1"))
+    database.patches_insert(package_ahriman.base, PkgbuildPatch("key", "patch3"))
+    database.patches_insert(package_python_schedule.base, PkgbuildPatch(None, "patch2"))
+    database.patches_remove(package_ahriman.base, ["key"])
+
+    assert database.patches_get(package_ahriman.base) == [PkgbuildPatch(None, "patch1")]
+    assert database.patches_get(package_python_schedule.base) == [PkgbuildPatch(None, "patch2")]
 
 
 def test_patches_insert_insert(database: SQLite, package_ahriman: Package) -> None:
     """
     must update patch in database
     """
-    database.patches_insert(package_ahriman.base, "patch_1")
-    assert database.patches_get(package_ahriman.base) == "patch_1"
+    database.patches_insert(package_ahriman.base, PkgbuildPatch(None, "patch1"))
+    assert database.patches_get(package_ahriman.base) == [PkgbuildPatch(None, "patch1")]
 
-    database.patches_insert(package_ahriman.base, "patch_2")
-    assert database.patches_get(package_ahriman.base) == "patch_2"
+    database.patches_insert(package_ahriman.base, PkgbuildPatch(None, "patch2"))
+    assert database.patches_get(package_ahriman.base) == [PkgbuildPatch(None, "patch2")]
diff --git a/tests/ahriman/core/formatters/conftest.py b/tests/ahriman/core/formatters/conftest.py
index 7246d195..a274db52 100644
--- a/tests/ahriman/core/formatters/conftest.py
+++ b/tests/ahriman/core/formatters/conftest.py
@@ -1,10 +1,11 @@
 import pytest
 
-from ahriman.core.formatters import AurPrinter, ConfigurationPrinter, PackagePrinter, StatusPrinter, StringPrinter, \
-    UpdatePrinter, UserPrinter, VersionPrinter
+from ahriman.core.formatters import AurPrinter, ConfigurationPrinter, PackagePrinter, PatchPrinter, StatusPrinter, \
+    StringPrinter, UpdatePrinter, UserPrinter, VersionPrinter
 from ahriman.models.aur_package import AURPackage
 from ahriman.models.build_status import BuildStatus
 from ahriman.models.package import Package
+from ahriman.models.pkgbuild_patch import PkgbuildPatch
 from ahriman.models.user import User
 
 
@@ -47,6 +48,20 @@ def package_ahriman_printer(package_ahriman: Package) -> PackagePrinter:
     return PackagePrinter(package_ahriman, BuildStatus())
 
 
+@pytest.fixture
+def patch_printer(package_ahriman: Package) -> PatchPrinter:
+    """
+    fixture for patch printer
+
+    Args:
+        package_ahriman(Package): package fixture
+
+    Returns:
+        PatchPrinter: patch printer test instance
+    """
+    return PatchPrinter(package_ahriman.base, [PkgbuildPatch("key", "value")])
+
+
 @pytest.fixture
 def status_printer() -> StatusPrinter:
     """
diff --git a/tests/ahriman/core/formatters/test_patch_printer.py b/tests/ahriman/core/formatters/test_patch_printer.py
new file mode 100644
index 00000000..059de51f
--- /dev/null
+++ b/tests/ahriman/core/formatters/test_patch_printer.py
@@ -0,0 +1,22 @@
+from ahriman.core.formatters import PatchPrinter
+
+
+def test_properties(patch_printer: PatchPrinter) -> None:
+    """
+    must return non empty properties list
+    """
+    assert patch_printer.properties()
+
+
+def test_properties_required(patch_printer: PatchPrinter) -> None:
+    """
+    must return all properties as required
+    """
+    assert all(prop.is_required for prop in patch_printer.properties())
+
+
+def test_title(patch_printer: PatchPrinter) -> None:
+    """
+    must return non empty title
+    """
+    assert patch_printer.title() == "ahriman"
diff --git a/tests/ahriman/core/repository/test_executor.py b/tests/ahriman/core/repository/test_executor.py
index beb46415..9cd55ab4 100644
--- a/tests/ahriman/core/repository/test_executor.py
+++ b/tests/ahriman/core/repository/test_executor.py
@@ -72,7 +72,7 @@ def test_process_remove_base(executor: Executor, package_ahriman: Package, mocke
     # must update status and remove package files
     tree_clear_mock.assert_called_once_with(package_ahriman.base)
     build_queue_mock.assert_called_once_with(package_ahriman.base)
-    patches_mock.assert_called_once_with(package_ahriman.base)
+    patches_mock.assert_called_once_with(package_ahriman.base, [])
     status_client_mock.assert_called_once_with(package_ahriman.base)
 
 
diff --git a/tests/ahriman/core/test_tree.py b/tests/ahriman/core/test_tree.py
index 402cab1a..ef5a7e86 100644
--- a/tests/ahriman/core/test_tree.py
+++ b/tests/ahriman/core/test_tree.py
@@ -49,8 +49,7 @@ def test_leaf_load(package_ahriman: Package, repository_paths: RepositoryPaths,
     leaf = Leaf.load(package_ahriman, repository_paths, database)
     assert leaf.package == package_ahriman
     assert leaf.dependencies == {"ahriman-dependency"}
-    load_mock.assert_called_once_with(
-        pytest.helpers.anyvar(int), package_ahriman, None, repository_paths)
+    load_mock.assert_called_once_with(pytest.helpers.anyvar(int), package_ahriman, [], repository_paths)
     dependencies_mock.assert_called_once_with(pytest.helpers.anyvar(int))
 
 
diff --git a/tests/ahriman/models/test_pkgbuild_patch.py b/tests/ahriman/models/test_pkgbuild_patch.py
index 9063ee06..0d40134d 100644
--- a/tests/ahriman/models/test_pkgbuild_patch.py
+++ b/tests/ahriman/models/test_pkgbuild_patch.py
@@ -5,6 +5,15 @@ from unittest.mock import MagicMock, call
 from ahriman.models.pkgbuild_patch import PkgbuildPatch
 
 
+def test_post_init() -> None:
+    """
+    must remove empty keys
+    """
+    assert PkgbuildPatch("", "value").key is None
+    assert PkgbuildPatch(None, "value").key is None
+    assert PkgbuildPatch("key", "value").key == "key"
+
+
 def test_is_function() -> None:
     """
     must correctly define key as function
@@ -13,6 +22,14 @@ def test_is_function() -> None:
     assert PkgbuildPatch("key()", "value").is_function
 
 
+def test_is_plain_diff() -> None:
+    """
+    must correctly define key as function
+    """
+    assert not PkgbuildPatch("key", "value").is_plain_diff
+    assert PkgbuildPatch(None, "value").is_plain_diff
+
+
 def test_quote() -> None:
     """
     must quote strings if unsafe flag is not set
@@ -32,6 +49,13 @@ def test_serialize() -> None:
     assert PkgbuildPatch("key", "4'2", unsafe=True).serialize() == "key=4'2"
 
 
+def test_serialize_plain_diff() -> None:
+    """
+    must correctly serialize function values
+    """
+    assert PkgbuildPatch(None, "{ value }").serialize() == "{ value }"
+
+
 def test_serialize_function() -> None:
     """
     must correctly serialize function values