diff --git a/docs/markdown/Contributing.md b/docs/markdown/Contributing.md
index e385be298..c0eea2978 100644
--- a/docs/markdown/Contributing.md
+++ b/docs/markdown/Contributing.md
@@ -167,6 +167,8 @@ Continuous integration systems currently used:
   allows `[skip ci]` anywhere in the commit messages.
 - [AppVeyor](https://www.appveyor.com/docs/how-to/filtering-commits/#skip-directive-in-commit-message)
   requires `[skip ci]` or `[skip appveyor]` in the commit title.
+- [Sider](https://sider.review)
+  runs Flake8 (see below)
 
 ## Documentation
 
@@ -208,6 +210,13 @@ $ cd meson
 $ flake8
 ```
 
+To run it automatically before committing:
+
+```console
+$ flake8 --install-hook=git
+$ git config --bool flake8.strict true
+```
+
 ## C/C++ coding style
 
 Meson has a bunch of test code in several languages. The rules for
diff --git a/mesonbuild/compilers/__init__.py b/mesonbuild/compilers/__init__.py
index 9070a9fed..bb6c9a99c 100644
--- a/mesonbuild/compilers/__init__.py
+++ b/mesonbuild/compilers/__init__.py
@@ -46,6 +46,8 @@ __all__ = [
 
     'ArmCCompiler',
     'ArmCPPCompiler',
+    'ArmclangCCompiler',
+    'ArmclangCPPCompiler',
     'CCompiler',
     'ClangCCompiler',
     'ClangCompiler',
diff --git a/mesonbuild/coredata.py b/mesonbuild/coredata.py
index a53fdde76..3725c6195 100644
--- a/mesonbuild/coredata.py
+++ b/mesonbuild/coredata.py
@@ -333,7 +333,6 @@ class CoreData:
                     'Default project to execute in Visual Studio',
                     '')
 
-
     def get_builtin_option(self, optname):
         if optname in self.builtins:
             return self.builtins[optname].value
diff --git a/mesonbuild/modules/__init__.py b/mesonbuild/modules/__init__.py
index e461144f2..6b6aa8ba9 100644
--- a/mesonbuild/modules/__init__.py
+++ b/mesonbuild/modules/__init__.py
@@ -1,7 +1,6 @@
 import os
 
 from .. import build
-from .. import mlog
 
 
 class ExtensionModule:
diff --git a/mesonbuild/modules/gnome.py b/mesonbuild/modules/gnome.py
index fabb0f92d..f2c5b2dff 100644
--- a/mesonbuild/modules/gnome.py
+++ b/mesonbuild/modules/gnome.py
@@ -919,7 +919,6 @@ This will become a hard error in the future.''')
             raise MesonException('gdbus_codegen takes at most two arguments, name and xml file.')
         namebase = args[0]
         xml_files = args[1:]
-        target_name = namebase + '-gdbus'
         cmd = [self.interpreter.find_program_impl('gdbus-codegen')]
         extra_args = mesonlib.stringlistify(kwargs.pop('extra_args', []))
         cmd += extra_args