diff --git a/build/valgrind/mach_commands.py b/build/valgrind/mach_commands.py
index 408c0be28c14..9e209f24c61c 100644
--- a/build/valgrind/mach_commands.py
+++ b/build/valgrind/mach_commands.py
@@ -48,7 +48,7 @@ class MachCommands(MachCommandBase):
         "--suppression multiple times to specify multiple suppression "
         "files.",
     )
-    def valgrind_test(self, suppressions):
+    def valgrind_test(self, command_context, suppressions):
 
         from mozfile import TemporaryDirectory
         from mozhttpd import MozHttpd
diff --git a/devtools/shared/css/generated/mach_commands.py b/devtools/shared/css/generated/mach_commands.py
index feeac78b1ae5..0a72e7043f25 100644
--- a/devtools/shared/css/generated/mach_commands.py
+++ b/devtools/shared/css/generated/mach_commands.py
@@ -45,7 +45,7 @@ class MachCommands(MachCommandBase):
         category="post-build",
         description="Rebuild the devtool's static css properties database.",
     )
-    def generate_css_db(self):
+    def generate_css_db(self, command_context):
         """Generate the static css properties database for devtools and write it to file."""
 
         print("Re-generating the css properties database...")
diff --git a/dom/bindings/mach_commands.py b/dom/bindings/mach_commands.py
index 28d278015691..596c4a28546c 100644
--- a/dom/bindings/mach_commands.py
+++ b/dom/bindings/mach_commands.py
@@ -33,7 +33,7 @@ class WebIDLProvider(MachCommandBase):
     @CommandArgument(
         "interface", nargs="+", help="Interface(s) whose examples to generate."
     )
-    def webidl_example(self, interface):
+    def webidl_example(self, command_context, interface):
         from mozwebidlcodegen import BuildSystemWebIDL
 
         manager = self._spawn(BuildSystemWebIDL).manager
@@ -46,7 +46,7 @@ class WebIDLProvider(MachCommandBase):
         parser=get_test_parser,
         description="Run WebIDL tests (Interface Browser parser).",
     )
-    def webidl_test(self, **kwargs):
+    def webidl_test(self, command_context, **kwargs):
         sys.path.insert(0, os.path.join(self.topsrcdir, "other-licenses", "ply"))
 
         # Ensure the topobjdir exists. On a Taskcluster test run there won't be
diff --git a/js/src/devtools/rootAnalysis/mach_commands.py b/js/src/devtools/rootAnalysis/mach_commands.py
index de38df738816..b4a4b58219dc 100644
--- a/js/src/devtools/rootAnalysis/mach_commands.py
+++ b/js/src/devtools/rootAnalysis/mach_commands.py
@@ -111,7 +111,7 @@ class MachCommands(MachCommandBase):
         order="declaration",
         description="Commands for running the static analysis for GC rooting hazards",
     )
-    def hazards(self):
+    def hazards(self, command_context):
         """Commands related to performing the GC rooting hazard analysis"""
         print("See `mach hazards --help` for a list of subcommands")
 
@@ -121,7 +121,7 @@ class MachCommands(MachCommandBase):
         "bootstrap",
         description="Install prerequisites for the hazard analysis",
     )
-    def bootstrap(self, **kwargs):
+    def bootstrap(self, command_context, **kwargs):
         orig_dir = os.getcwd()
         os.chdir(self.ensure_dir_exists(self.tools_dir))
         try:
@@ -142,7 +142,7 @@ class MachCommands(MachCommandBase):
         metavar="FILENAME",
         help="Build with the given mozconfig.",
     )
-    def build_shell(self, **kwargs):
+    def build_shell(self, command_context, **kwargs):
         """Build a JS shell to use to run the rooting hazard analysis."""
         # The JS shell requires some specific configuration settings to execute
         # the hazard analysis code, and configuration is done via mozconfig.
@@ -215,7 +215,7 @@ no shell found in %s -- must build the JS shell with `mach hazards build-shell`
     @CommandArgument(
         "--work-dir", default=None, help="Directory for output and working files."
     )
-    def gather_hazard_data(self, **kwargs):
+    def gather_hazard_data(self, command_context, **kwargs):
         """Gather analysis information by compiling the tree"""
         application = kwargs["application"]
         objdir = kwargs["haz_objdir"]
@@ -279,7 +279,7 @@ no shell found in %s -- must build the JS shell with `mach hazards build-shell`
         default=os.environ.get("HAZ_OBJDIR"),
         help="Write object files to this directory.",
     )
-    def inner_compile(self, **kwargs):
+    def inner_compile(self, command_context, **kwargs):
         """Build a source tree and gather analysis information while running
         under the influence of the analysis collection server."""
 
@@ -346,7 +346,7 @@ no shell found in %s -- must build the JS shell with `mach hazards build-shell`
     @CommandArgument(
         "--work-dir", default=None, help="Directory for output and working files."
     )
-    def analyze(self, application, shell_objdir, work_dir):
+    def analyze(self, command_context, application, shell_objdir, work_dir):
         """Analyzed gathered data for rooting hazards"""
 
         shell = self.ensure_shell(shell_objdir)
@@ -374,7 +374,7 @@ no shell found in %s -- must build the JS shell with `mach hazards build-shell`
         default=None,
         help="objdir containing the optimized JS shell for running the analysis.",
     )
-    def self_test(self, shell_objdir):
+    def self_test(self, command_context, shell_objdir):
         """Analyzed gathered data for rooting hazards"""
         shell = self.ensure_shell(shell_objdir)
         args = [
diff --git a/layout/tools/reftest/mach_commands.py b/layout/tools/reftest/mach_commands.py
index e1ff5fbc709d..f2b160fb5663 100644
--- a/layout/tools/reftest/mach_commands.py
+++ b/layout/tools/reftest/mach_commands.py
@@ -236,7 +236,7 @@ class MachCommands(MachCommandBase):
         description="Run reftests (layout and graphics correctness).",
         parser=get_parser,
     )
-    def run_reftest(self, **kwargs):
+    def run_reftest(self, command_context, **kwargs):
         kwargs["suite"] = "reftest"
         return self._run_reftest(**kwargs)
 
@@ -246,7 +246,7 @@ class MachCommands(MachCommandBase):
         description="Run js/src/tests in the browser.",
         parser=get_parser,
     )
-    def run_jstestbrowser(self, **kwargs):
+    def run_jstestbrowser(self, command_context, **kwargs):
         if "--enable-js-shell" not in self.mozconfig["configure_args"]:
             raise Exception(
                 "jstestbrowser requires --enable-js-shell be specified in mozconfig."
@@ -263,7 +263,7 @@ class MachCommands(MachCommandBase):
         description="Run crashtests (Check if crashes on a page).",
         parser=get_parser,
     )
-    def run_crashtest(self, **kwargs):
+    def run_crashtest(self, command_context, **kwargs):
         kwargs["suite"] = "crashtest"
         return self._run_reftest(**kwargs)
 
diff --git a/layout/tools/reftest/mach_test_package_commands.py b/layout/tools/reftest/mach_test_package_commands.py
index a671d555cc0d..0ee2053b381c 100644
--- a/layout/tools/reftest/mach_test_package_commands.py
+++ b/layout/tools/reftest/mach_test_package_commands.py
@@ -115,7 +115,7 @@ class ReftestCommands(MachCommandBase):
         description="Run the reftest harness.",
         parser=setup_argument_parser,
     )
-    def reftest(self, **kwargs):
+    def reftest(self, command_context, **kwargs):
         self._mach_context.activate_mozharness_venv()
         kwargs["suite"] = "reftest"
         return run_reftest(self._mach_context, **kwargs)
diff --git a/mobile/android/mach_commands.py b/mobile/android/mach_commands.py
index 691977425475..4308b38010de 100644
--- a/mobile/android/mach_commands.py
+++ b/mobile/android/mach_commands.py
@@ -57,7 +57,7 @@ class MachCommands(MachCommandBase):
         description="Run Android-specific commands.",
         conditions=[conditions.is_android],
     )
-    def android(self):
+    def android(self, command_context):
         pass
 
     @SubCommand(
@@ -67,8 +67,9 @@ class MachCommands(MachCommandBase):
         See http://firefox-source-docs.mozilla.org/build/buildsystem/toolchains.html#firefox-for-android-with-gradle""",  # NOQA: E501
     )
     @CommandArgument("args", nargs=argparse.REMAINDER)
-    def android_assemble_app(self, args):
+    def android_assemble_app(self, command_context, args):
         ret = self.gradle(
+            command_context,
             self.substs["GRADLE_ANDROID_APP_TASKS"] + ["-x", "lint"] + args,
             verbose=True,
         )
@@ -86,7 +87,7 @@ class MachCommands(MachCommandBase):
         help="config files, " "like [/path/to/ClassName-classes.txt]+",
     )
     @CommandArgument("args", nargs=argparse.REMAINDER)
-    def android_generate_sdk_bindings(self, inputs, args):
+    def android_generate_sdk_bindings(self, command_context, inputs, args):
         import itertools
 
         def stem(input):
@@ -101,6 +102,7 @@ class MachCommands(MachCommandBase):
         )
 
         ret = self.gradle(
+            command_context,
             self.substs["GRADLE_ANDROID_GENERATE_SDK_BINDINGS_TASKS"]
             + [bindings_args]
             + args,
@@ -115,8 +117,9 @@ class MachCommands(MachCommandBase):
         """Generate GeckoView JNI wrappers used when building GeckoView.""",
     )
     @CommandArgument("args", nargs=argparse.REMAINDER)
-    def android_generate_generated_jni_wrappers(self, args):
+    def android_generate_generated_jni_wrappers(self, command_context, args):
         ret = self.gradle(
+            command_context,
             self.substs["GRADLE_ANDROID_GENERATE_GENERATED_JNI_WRAPPERS_TASKS"] + args,
             verbose=True,
         )
@@ -129,7 +132,7 @@ class MachCommands(MachCommandBase):
         """Run Android api-lint.
 REMOVED/DEPRECATED: Use 'mach lint --linter android-api-lint'.""",
     )
-    def android_apilint_REMOVED(self):
+    def android_apilint_REMOVED(self, command_context):
         print(LINT_DEPRECATION_MESSAGE)
         return 1
 
@@ -139,7 +142,7 @@ REMOVED/DEPRECATED: Use 'mach lint --linter android-api-lint'.""",
         """Run Android test.
 REMOVED/DEPRECATED: Use 'mach lint --linter android-test'.""",
     )
-    def android_test_REMOVED(self):
+    def android_test_REMOVED(self, command_context):
         print(LINT_DEPRECATION_MESSAGE)
         return 1
 
@@ -149,7 +152,7 @@ REMOVED/DEPRECATED: Use 'mach lint --linter android-test'.""",
         """Run Android lint.
 REMOVED/DEPRECATED: Use 'mach lint --linter android-lint'.""",
     )
-    def android_lint_REMOVED(self):
+    def android_lint_REMOVED(self, command_context):
         print(LINT_DEPRECATION_MESSAGE)
         return 1
 
@@ -159,7 +162,7 @@ REMOVED/DEPRECATED: Use 'mach lint --linter android-lint'.""",
         """Run Android checkstyle.
 REMOVED/DEPRECATED: Use 'mach lint --linter android-checkstyle'.""",
     )
-    def android_checkstyle_REMOVED(self):
+    def android_checkstyle_REMOVED(self, command_context):
         print(LINT_DEPRECATION_MESSAGE)
         return 1
 
@@ -170,11 +173,12 @@ REMOVED/DEPRECATED: Use 'mach lint --linter android-checkstyle'.""",
         See http://firefox-source-docs.mozilla.org/build/buildsystem/toolchains.html#firefox-for-android-with-gradle""",  # NOQA: E501
     )
     @CommandArgument("args", nargs=argparse.REMAINDER)
-    def android_gradle_dependencies(self, args):
+    def android_gradle_dependencies(self, command_context, args):
         # We don't want to gate producing dependency archives on clean
         # lint or checkstyle, particularly because toolchain versions
         # can change the outputs for those processes.
         self.gradle(
+            command_context,
             self.substs["GRADLE_ANDROID_DEPENDENCIES_TASKS"] + ["--continue"] + args,
             verbose=True,
         )
@@ -188,17 +192,20 @@ REMOVED/DEPRECATED: Use 'mach lint --linter android-checkstyle'.""",
         See http://firefox-source-docs.mozilla.org/build/buildsystem/toolchains.html#firefox-for-android-with-gradle""",  # NOQA: E501
     )
     @CommandArgument("args", nargs=argparse.REMAINDER)
-    def android_archive_geckoview(self, args):
+    def android_archive_geckoview(self, command_context, args):
         ret = self.gradle(
-            self.substs["GRADLE_ANDROID_ARCHIVE_GECKOVIEW_TASKS"] + args, verbose=True
+            command_context,
+            self.substs["GRADLE_ANDROID_ARCHIVE_GECKOVIEW_TASKS"] + args,
+            verbose=True,
         )
 
         return ret
 
     @SubCommand("android", "build-geckoview_example", """Build geckoview_example """)
     @CommandArgument("args", nargs=argparse.REMAINDER)
-    def android_build_geckoview_example(self, args):
+    def android_build_geckoview_example(self, command_context, args):
         self.gradle(
+            command_context,
             self.substs["GRADLE_ANDROID_BUILD_GECKOVIEW_EXAMPLE_TASKS"] + args,
             verbose=True,
         )
@@ -214,8 +221,9 @@ REMOVED/DEPRECATED: Use 'mach lint --linter android-checkstyle'.""",
         "android", "install-geckoview_example", """Install geckoview_example """
     )
     @CommandArgument("args", nargs=argparse.REMAINDER)
-    def android_install_geckoview_example(self, args):
+    def android_install_geckoview_example(self, command_context, args):
         self.gradle(
+            command_context,
             self.substs["GRADLE_ANDROID_INSTALL_GECKOVIEW_EXAMPLE_TASKS"] + args,
             verbose=True,
         )
@@ -260,7 +268,13 @@ REMOVED/DEPRECATED: Use 'mach lint --linter android-checkstyle'.""",
         help="Use the specified message for commits.",
     )
     def android_geckoview_docs(
-        self, archive, upload, upload_branch, javadoc_path, upload_message
+        self,
+        command_context,
+        archive,
+        upload,
+        upload_branch,
+        javadoc_path,
+        upload_message,
     ):
 
         tasks = (
@@ -269,7 +283,7 @@ REMOVED/DEPRECATED: Use 'mach lint --linter android-checkstyle'.""",
             else self.substs["GRADLE_ANDROID_GECKOVIEW_DOCS_TASKS"]
         )
 
-        ret = self.gradle(tasks, verbose=True)
+        ret = self.gradle(command_context, tasks, verbose=True)
         if ret or not upload:
             return ret
 
@@ -383,7 +397,7 @@ REMOVED/DEPRECATED: Use 'mach lint --linter android-checkstyle'.""",
         help="Verbose output for what commands the build is running.",
     )
     @CommandArgument("args", nargs=argparse.REMAINDER)
-    def gradle(self, args, verbose=False):
+    def gradle(self, command_context, args, verbose=False):
         if not verbose:
             # Avoid logging the command
             self.log_manager.terminal_handler.setLevel(logging.CRITICAL)
@@ -442,7 +456,7 @@ REMOVED/DEPRECATED: Use 'mach lint --linter android-checkstyle'.""",
         )
 
     @Command("gradle-install", category="devenv", conditions=[REMOVED])
-    def gradle_install_REMOVED(self):
+    def gradle_install_REMOVED(self, command_context):
         pass
 
 
@@ -486,7 +500,13 @@ class AndroidEmulatorCommands(MachCommandBase):
         "--verbose", action="store_true", help="Log informative status messages."
     )
     def emulator(
-        self, version, wait=False, force_update=False, gpu=None, verbose=False
+        self,
+        command_context,
+        version,
+        wait=False,
+        force_update=False,
+        gpu=None,
+        verbose=False,
     ):
         from mozrunner.devices.android_device import AndroidEmulator
 
diff --git a/python/mach/docs/commands.rst b/python/mach/docs/commands.rst
index 2d014af9f744..70dbcb3d7077 100644
--- a/python/mach/docs/commands.rst
+++ b/python/mach/docs/commands.rst
@@ -17,7 +17,11 @@ The important decorators are as follows:
   A method decorator that denotes that the method should be called when
   the specified command is requested. The decorator takes a command name
   as its first argument and a number of additional arguments to
-  configure the behavior of the command.
+  configure the behavior of the command. The decorated method must take a
+  ``command_context`` argument as its first (after ``self``).
+  ``command_context`` is a properly configured instance of a ``MozbuildObject``
+  subclass, meaning it can be used for accessing things like the current config
+  and running processes.
 
 :py:func:`CommandArgument <mach.decorators.CommandArgument>`
   A method decorator that defines an argument to the command. Its
@@ -51,7 +55,7 @@ Here is a complete example:
        @Command('doit', help='Do ALL OF THE THINGS.')
        @CommandArgument('--force', '-f', action='store_true',
            help='Force doing it.')
-       def doit(self, force=False):
+       def doit(self, command_context, force=False):
            # Do stuff here.
 
 When the module is loaded, the decorators tell mach about all handlers.
@@ -101,7 +105,7 @@ Here is an example:
            self.build_path = ...
 
        @Command('run_tests', conditions=[build_available])
-       def run_tests(self):
+       def run_tests(self, command_context):
            # Do stuff here.
 
 It is important to make sure that any state needed by the condition is
diff --git a/python/mach/mach/commands/commandinfo.py b/python/mach/mach/commands/commandinfo.py
index 93eb52e9249c..3c9510dc8cd1 100644
--- a/python/mach/mach/commands/commandinfo.py
+++ b/python/mach/mach/commands/commandinfo.py
@@ -128,7 +128,7 @@ class BuiltinCommands(MachCommandBase):
         return commands_info
 
     @Command("mach-commands", category="misc", description="List all mach commands.")
-    def run_commands(self):
+    def run_commands(self, command_context):
         print("\n".join(self.commands))
 
     @Command(
@@ -143,7 +143,7 @@ class BuiltinCommands(MachCommandBase):
         nargs="?",
         help="Only display commands containing given substring.",
     )
-    def run_debug_commands(self, match=None):
+    def run_debug_commands(self, command_context, match=None):
         import inspect
 
         for command, handler in self.command_handlers.items():
@@ -169,7 +169,7 @@ class BuiltinCommands(MachCommandBase):
     @CommandArgument(
         "args", default=None, nargs=argparse.REMAINDER, help="Command to complete."
     )
-    def run_completion(self, args):
+    def run_completion(self, command_context, args):
         if not args:
             print("\n".join(self.commands))
             return
@@ -231,7 +231,7 @@ class BuiltinCommands(MachCommandBase):
         default=None,
         help="File path to save completion script.",
     )
-    def completion_bash(self, outfile):
+    def completion_bash(self, command_context, outfile):
         commands_subcommands = []
         case_options = []
         case_subcommands = []
@@ -325,7 +325,7 @@ class BuiltinCommands(MachCommandBase):
         default=None,
         help="File path to save completion script.",
     )
-    def completion_zsh(self, outfile):
+    def completion_zsh(self, command_context, outfile):
         commands_descriptions = []
         commands_subcommands = []
         case_options = []
@@ -420,7 +420,7 @@ class BuiltinCommands(MachCommandBase):
         default=None,
         help="File path to save completion script.",
     )
-    def completion_fish(self, outfile):
+    def completion_fish(self, command_context, outfile):
         def _append_opt_strs(comp, opt_strs):
             for opt in opt_strs:
                 if opt.startswith("--"):
diff --git a/python/mach/mach/commands/settings.py b/python/mach/mach/commands/settings.py
index 22e8ba9c4298..812bfd939c35 100644
--- a/python/mach/mach/commands/settings.py
+++ b/python/mach/mach/commands/settings.py
@@ -38,7 +38,7 @@ class Settings(MachCommandBase):
         action="store_true",
         help="Show settings in a concise list",
     )
-    def run_settings(self, short=None):
+    def run_settings(self, command_context, short=None):
         """List available settings."""
         types = {v: k for k, v in TYPE_CLASSES.items()}
         wrapper = TextWrapper(initial_indent="# ", subsequent_indent="# ")
diff --git a/python/mach/mach/registrar.py b/python/mach/mach/registrar.py
index ef1886992145..6db52957a8fb 100644
--- a/python/mach/mach/registrar.py
+++ b/python/mach/mach/registrar.py
@@ -102,9 +102,9 @@ class MachRegistrar(object):
         if debug_command:
             import pdb
 
-            result = pdb.runcall(fn, **kwargs)
+            result = pdb.runcall(fn, instance, **kwargs)
         else:
-            result = fn(**kwargs)
+            result = fn(instance, **kwargs)
 
         end_time = time.time()
 
diff --git a/python/mach/mach/test/providers/commands.py b/python/mach/mach/test/providers/commands.py
index 9463c6b4039f..00cda7775bb3 100644
--- a/python/mach/mach/test/providers/commands.py
+++ b/python/mach/mach/test/providers/commands.py
@@ -31,15 +31,15 @@ class MachCommands(MachCommandBase):
 
     @Command("cmd_foo", category="testing")
     @CommandArgument("--arg", default=None, help="Argument help.")
-    def run_foo(self):
+    def run_foo(self, command_context):
         pass
 
     @Command("cmd_bar", category="testing", conditions=[partial(is_bar, False)])
-    def run_bar(self):
+    def run_bar(self, command_context):
         pass
 
     @Command(
         "cmd_foobar", category="testing", conditions=[is_foo, partial(is_bar, True)]
     )
-    def run_foobar(self):
+    def run_foobar(self, command_context):
         pass
diff --git a/python/mach/mach/test/providers/conditions.py b/python/mach/mach/test/providers/conditions.py
index 2ca619fa4d8e..9801bd1fc33c 100644
--- a/python/mach/mach/test/providers/conditions.py
+++ b/python/mach/mach/test/providers/conditions.py
@@ -28,15 +28,15 @@ class ConditionsProvider(MachCommandBase):
     bar = False
 
     @Command("cmd_foo", category="testing", conditions=[is_foo])
-    def run_foo(self):
+    def run_foo(self, command_context):
         pass
 
     @Command("cmd_bar", category="testing", conditions=[is_bar])
-    def run_bar(self):
+    def run_bar(self, command_context):
         pass
 
     @Command("cmd_foobar", category="testing", conditions=[is_foo, is_bar])
-    def run_foobar(self):
+    def run_foobar(self, command_context):
         pass
 
 
@@ -48,13 +48,13 @@ class ConditionsContextProvider(MachCommandBase):
         self.bar = self._mach_context.bar
 
     @Command("cmd_foo_ctx", category="testing", conditions=[is_foo])
-    def run_foo(self):
+    def run_foo(self, command_context):
         pass
 
     @Command("cmd_bar_ctx", category="testing", conditions=[is_bar])
-    def run_bar(self):
+    def run_bar(self, command_context):
         pass
 
     @Command("cmd_foobar_ctx", category="testing", conditions=[is_foo, is_bar])
-    def run_foobar(self):
+    def run_foobar(self, command_context):
         pass
diff --git a/python/mach/mach/test/providers/throw.py b/python/mach/mach/test/providers/throw.py
index b562ee1566e5..392f444bb749 100644
--- a/python/mach/mach/test/providers/throw.py
+++ b/python/mach/mach/test/providers/throw.py
@@ -18,10 +18,10 @@ from mozbuild.base import MachCommandBase
 class TestCommandProvider(MachCommandBase):
     @Command("throw", category="testing")
     @CommandArgument("--message", "-m", default="General Error")
-    def throw(self, message):
+    def throw(self, command_context, message):
         raise Exception(message)
 
     @Command("throw_deep", category="testing")
     @CommandArgument("--message", "-m", default="General Error")
-    def throw_deep(self, message):
+    def throw_deep(self, command_context, message):
         throw2.throw_deep(message)
diff --git a/python/mach/mach/test/test_decorators.py b/python/mach/mach/test/test_decorators.py
index 93215c0fb8c1..f4a82d126042 100644
--- a/python/mach/mach/test/test_decorators.py
+++ b/python/mach/mach/test/test_decorators.py
@@ -37,7 +37,7 @@ def test_register_command_with_argument(registrar):
     class CommandFoo(MachCommandBase):
         @Command("cmd_foo", category="testing")
         @CommandArgument("--arg", default=None, help="Argument help.")
-        def run_foo(self, arg):
+        def run_foo(self, command_context, arg):
             inner_function(arg)
 
     registrar.dispatch("cmd_foo", context, arg="argument")
@@ -56,12 +56,14 @@ def test_register_command_with_metrics_path(registrar):
     @CommandProvider
     class CommandFoo(MachCommandBase):
         @Command("cmd_foo", category="testing", metrics_path=metrics_path)
-        def run_foo(self):
+        def run_foo(self, command_context):
             assert self.metrics == metrics_mock
+            assert command_context.metrics == metrics_mock
 
         @SubCommand("cmd_foo", "sub_foo", metrics_path=metrics_path + "2")
-        def run_subfoo(self):
+        def run_subfoo(self, command_context):
             assert self.metrics == metrics_mock
+            assert command_context.metrics == metrics_mock
 
     registrar.dispatch("cmd_foo", context)
 
@@ -83,17 +85,25 @@ def test_register_command_sets_up_class_at_runtime(registrar):
     @CommandProvider
     class CommandFoo(MachCommandBase):
         @Command("cmd_foo", category="testing", virtualenv_name="env_foo")
-        def run_foo(self):
+        def run_foo(self, command_context):
             assert (
                 os.path.basename(self.virtualenv_manager.virtualenv_root) == "env_foo"
             )
+            assert (
+                os.path.basename(command_context.virtualenv_manager.virtualenv_root)
+                == "env_foo"
+            )
             inner_function("foo")
 
         @Command("cmd_bar", category="testing", virtualenv_name="env_bar")
-        def run_bar(self):
+        def run_bar(self, command_context):
             assert (
                 os.path.basename(self.virtualenv_manager.virtualenv_root) == "env_bar"
             )
+            assert (
+                os.path.basename(command_context.virtualenv_manager.virtualenv_root)
+                == "env_bar"
+            )
             inner_function("bar")
 
     registrar.dispatch("cmd_foo", context)
@@ -108,7 +118,7 @@ def test_cannot_create_command_nonexisting_category(registrar):
         @CommandProvider
         class CommandFoo(MachCommandBase):
             @Command("cmd_foo", category="bar")
-            def run_foo(self):
+            def run_foo(self, command_context):
                 pass
 
 
@@ -118,7 +128,7 @@ def test_subcommand_requires_parent_to_exist(registrar):
         @CommandProvider
         class CommandFoo(MachCommandBase):
             @SubCommand("sub_foo", "foo")
-            def run_foo(self):
+            def run_foo(self, command_context):
                 pass
 
 
diff --git a/python/mach_commands.py b/python/mach_commands.py
index 7e1ce9bf43bc..74abe042ae0e 100644
--- a/python/mach_commands.py
+++ b/python/mach_commands.py
@@ -61,7 +61,14 @@ class MachCommands(MachCommandBase):
     )
     @CommandArgument("args", nargs=argparse.REMAINDER)
     def python(
-        self, no_virtualenv, no_activate, exec_file, ipython, requirements, args
+        self,
+        command_context,
+        no_virtualenv,
+        no_activate,
+        exec_file,
+        ipython,
+        requirements,
+        args,
     ):
         # Avoid logging the command
         self.log_manager.terminal_handler.setLevel(logging.CRITICAL)
@@ -165,7 +172,7 @@ class MachCommands(MachCommandBase):
             "passed as it is to pytest"
         ),
     )
-    def python_test(self, *args, **kwargs):
+    def python_test(self, command_context, *args, **kwargs):
         try:
             tempdir = str(tempfile.mkdtemp(suffix="-python-test"))
             if six.PY2:
diff --git a/python/mozboot/mozboot/mach_commands.py b/python/mozboot/mozboot/mach_commands.py
index 8b8040e59684..a9f7f1e03721 100644
--- a/python/mozboot/mozboot/mach_commands.py
+++ b/python/mozboot/mozboot/mach_commands.py
@@ -38,7 +38,12 @@ class Bootstrap(MachCommandBase):
         action="store_true",
         help="Only execute actions that leave the system " "configuration alone.",
     )
-    def bootstrap(self, application_choice=None, no_system_changes=False):
+    def bootstrap(
+        self,
+        command_context,
+        application_choice=None,
+        no_system_changes=False,
+    ):
         from mozboot.bootstrap import Bootstrapper
 
         bootstrapper = Bootstrapper(
@@ -63,7 +68,7 @@ class VersionControlCommands(MachCommandBase):
         action="store_true",
         help="Only update recommended extensions, don't run the wizard.",
     )
-    def vcs_setup(self, update_only=False):
+    def vcs_setup(self, command_context, update_only=False):
         """Ensure a Version Control System (Mercurial or Git) is optimally
         configured.
 
diff --git a/python/mozbuild/mozbuild/artifact_commands.py b/python/mozbuild/mozbuild/artifact_commands.py
index 6e9c892230c7..fea86658cb1e 100644
--- a/python/mozbuild/mozbuild/artifact_commands.py
+++ b/python/mozbuild/mozbuild/artifact_commands.py
@@ -72,7 +72,7 @@ class PackageFrontend(MachCommandBase):
         category="post-build",
         description="Use pre-built artifacts to build Firefox.",
     )
-    def artifact(self):
+    def artifact(self, command_context):
         """Download, cache, and install pre-built binary artifacts to build Firefox.
 
         Use |mach build| as normal to freshen your installed binary libraries:
@@ -176,6 +176,7 @@ class PackageFrontend(MachCommandBase):
     )
     def artifact_install(
         self,
+        command_context,
         source=None,
         skip_cache=False,
         tree=None,
@@ -207,7 +208,7 @@ class PackageFrontend(MachCommandBase):
         "clear-cache",
         "Delete local artifacts and reset local artifact cache.",
     )
-    def artifact_clear_cache(self, tree=None, job=None, verbose=False):
+    def artifact_clear_cache(self, command_context, tree=None, job=None, verbose=False):
         self._set_log_level(verbose)
         artifacts = self._make_artifacts(tree=tree, job=job)
         artifacts.clear_cache()
@@ -259,6 +260,7 @@ class PackageFrontend(MachCommandBase):
     )
     def artifact_toolchain(
         self,
+        command_context,
         verbose=False,
         cache_dir=None,
         skip_cache=False,
diff --git a/python/mozbuild/mozbuild/backend/mach_commands.py b/python/mozbuild/mozbuild/backend/mach_commands.py
index d2f0af2d62ca..da93474b1410 100644
--- a/python/mozbuild/mozbuild/backend/mach_commands.py
+++ b/python/mozbuild/mozbuild/backend/mach_commands.py
@@ -29,7 +29,7 @@ class MachCommands(MachCommandBase):
     )
     @CommandArgument("ide", choices=["eclipse", "visualstudio", "vscode"])
     @CommandArgument("args", nargs=argparse.REMAINDER)
-    def run(self, ide, args):
+    def run(self, command_context, ide, args):
         if ide == "eclipse":
             backend = "CppEclipse"
         elif ide == "visualstudio":
diff --git a/python/mozbuild/mozbuild/build_commands.py b/python/mozbuild/mozbuild/build_commands.py
index 11a6a69aa4ac..a0d9f1f0eb59 100644
--- a/python/mozbuild/mozbuild/build_commands.py
+++ b/python/mozbuild/mozbuild/build_commands.py
@@ -64,7 +64,15 @@ class Build(MachCommandBase):
         action="store_true",
         help="Keep building after an error has occurred",
     )
-    def build(self, what=None, jobs=0, directory=None, verbose=False, keep_going=False):
+    def build(
+        self,
+        context_context,
+        what=None,
+        jobs=0,
+        directory=None,
+        verbose=False,
+        keep_going=False,
+    ):
         """Build the source tree.
 
         With no arguments, this will perform a full build.
@@ -168,7 +176,13 @@ class Build(MachCommandBase):
     @CommandArgument(
         "options", default=None, nargs=argparse.REMAINDER, help="Configure options"
     )
-    def configure(self, options=None, buildstatus_messages=False, line_handler=None):
+    def configure(
+        self,
+        command_context,
+        options=None,
+        buildstatus_messages=False,
+        line_handler=None,
+    ):
         from mozbuild.controller.building import BuildDriver
 
         self.log_manager.enable_all_structured_loggers()
@@ -203,7 +217,9 @@ class Build(MachCommandBase):
         help="Web browser to automatically open. See webbrowser Python module.",
     )
     @CommandArgument("--url", help="URL of JSON document to display")
-    def resource_usage(self, address=None, port=None, browser=None, url=None):
+    def resource_usage(
+        self, command_context, address=None, port=None, browser=None, url=None
+    ):
         import webbrowser
         from mozbuild.html_build_viewer import BuildViewerServer
 
@@ -258,7 +274,9 @@ class Build(MachCommandBase):
         action="store_true",
         help="Do everything except writing files out.",
     )
-    def build_backend(self, backend, diff=False, verbose=False, dry_run=False):
+    def build_backend(
+        self, command_context, backend, diff=False, verbose=False, dry_run=False
+    ):
         python = self.virtualenv_manager.python_path
         config_status = os.path.join(self.topobjdir, "config.status")
 
diff --git a/python/mozbuild/mozbuild/code_analysis/mach_commands.py b/python/mozbuild/mozbuild/code_analysis/mach_commands.py
index f8975f25c81d..a600c48d3fb0 100644
--- a/python/mozbuild/mozbuild/code_analysis/mach_commands.py
+++ b/python/mozbuild/mozbuild/code_analysis/mach_commands.py
@@ -203,7 +203,7 @@ class StaticAnalysis(MachCommandBase):
         category="testing",
         description="Run C++ static analysis checks",
     )
-    def static_analysis(self):
+    def static_analysis(self, command_context):
         # If no arguments are provided, just print a help message.
         """Detailed documentation:
         https://firefox-source-docs.mozilla.org/code-quality/static-analysis.html
@@ -289,6 +289,7 @@ class StaticAnalysis(MachCommandBase):
     )
     def check(
         self,
+        command_context,
         source=None,
         jobs=2,
         strip=1,
@@ -453,6 +454,7 @@ class StaticAnalysis(MachCommandBase):
     )
     def check_coverity(
         self,
+        command_context,
         source=[],
         output=None,
         coverity_output_path=None,
@@ -1049,6 +1051,7 @@ class StaticAnalysis(MachCommandBase):
     @CommandArgument("--output", default=None, help="Write infer json output in a file")
     def check_java(
         self,
+        command_context,
         source=["mobile"],
         jobs=2,
         strip=1,
@@ -1424,7 +1427,12 @@ class StaticAnalysis(MachCommandBase):
         help="Checkers that are going to be auto-tested.",
     )
     def autotest(
-        self, verbose=False, dump_results=False, intree_tool=False, checker_names=[]
+        self,
+        command_context,
+        verbose=False,
+        dump_results=False,
+        intree_tool=False,
+        checker_names=[],
     ):
         # If 'dump_results' is True than we just want to generate the issues files for each
         # checker in particulat and thus 'force_download' becomes 'False' since we want to
@@ -1983,6 +1991,7 @@ class StaticAnalysis(MachCommandBase):
     )
     def install(
         self,
+        command_context,
         source=None,
         skip_cache=False,
         force=False,
@@ -2004,7 +2013,7 @@ class StaticAnalysis(MachCommandBase):
         "clear-cache",
         "Delete local helpers and reset static analysis helper tool cache",
     )
-    def clear_cache(self, verbose=False):
+    def clear_cache(self, command_context, verbose=False):
         self._set_log_level(verbose)
         rc = self._get_clang_tools(
             force=True, download_if_needed=True, skip_cache=True, verbose=verbose
@@ -2028,7 +2037,7 @@ class StaticAnalysis(MachCommandBase):
         "print-checks",
         "Print a list of the static analysis checks performed by default",
     )
-    def print_checks(self, verbose=False):
+    def print_checks(self, command_context, verbose=False):
         self._set_log_level(verbose)
         rc = self._get_clang_tools(verbose=verbose)
 
@@ -2080,7 +2089,7 @@ class StaticAnalysis(MachCommandBase):
         "When reading from stdin, Prettier assumes this "
         "filename to decide which style and parser to use.",
     )
-    def prettier_format(self, path, assume_filename):
+    def prettier_format(self, command_context, path, assume_filename):
         # With assume_filename we want to have stdout clean since the result of the
         # format will be redirected to stdout.
 
@@ -2115,7 +2124,7 @@ class StaticAnalysis(MachCommandBase):
     @CommandArgument(
         "source", nargs="*", help="Source files to be compiled checked (regex on path)."
     )
-    def check_syntax(self, source, verbose=False):
+    def check_syntax(self, command_context, source, verbose=False):
         self._set_log_level(verbose)
         self.log_manager.enable_unstructured()
 
@@ -2276,6 +2285,7 @@ class StaticAnalysis(MachCommandBase):
     )
     def clang_format(
         self,
+        command_context,
         assume_filename,
         path,
         commit,
@@ -2492,7 +2502,7 @@ class StaticAnalysis(MachCommandBase):
                     return (1, None, None)
                 os.environ["AUTOCLOBBER"] = "1"
 
-            rc = builder.configure()
+            rc = builder.configure(self)
             if rc != 0:
                 return (rc, config, ran_configure)
             ran_configure = True
@@ -2530,7 +2540,9 @@ class StaticAnalysis(MachCommandBase):
                 "created yet, creating it now..."
             )
             builder = Build(self._mach_context, None)
-            rc = builder.build_backend(["StaticAnalysis"], verbose=verbose)
+            rc = builder.build_backend(
+                self._mach_context, ["StaticAnalysis"], verbose=verbose
+            )
             if rc != 0:
                 return rc
             assert os.path.exists(self._compile_db)
diff --git a/python/mozbuild/mozbuild/compilation/codecomplete.py b/python/mozbuild/mozbuild/compilation/codecomplete.py
index cf82612a138e..f2e9c35fd254 100644
--- a/python/mozbuild/mozbuild/compilation/codecomplete.py
+++ b/python/mozbuild/mozbuild/compilation/codecomplete.py
@@ -31,7 +31,7 @@ class Introspection(MachCommandBase):
     @CommandArgument(
         "what", default=None, help="Source file to display compilation flags for"
     )
-    def compileflags(self, what):
+    def compileflags(self, command_context, what):
         from mozbuild.util import resolve_target_to_make
         from mozbuild.compilation import util
 
diff --git a/python/mozbuild/mozbuild/frontend/mach_commands.py b/python/mozbuild/mozbuild/frontend/mach_commands.py
index 385151595f75..a06199c318a3 100644
--- a/python/mozbuild/mozbuild/frontend/mach_commands.py
+++ b/python/mozbuild/mozbuild/frontend/mach_commands.py
@@ -46,7 +46,7 @@ class MozbuildFileCommands(MachCommandBase):
         action="store_true",
         help="Print symbol names only.",
     )
-    def reference(self, symbol, name_only=False):
+    def reference(self, command_context, symbol, name_only=False):
         # mozbuild.sphinx imports some Sphinx modules, so we need to be sure
         # the optional Sphinx package is installed.
         self.activate_virtualenv()
@@ -101,7 +101,7 @@ class MozbuildFileCommands(MachCommandBase):
     @Command(
         "file-info", category="build-dev", description="Query for metadata about files."
     )
-    def file_info(self):
+    def file_info(self, command_context):
         """Show files metadata derived from moz.build files.
 
         moz.build files contain "Files" sub-contexts for declaring metadata
@@ -124,7 +124,7 @@ class MozbuildFileCommands(MachCommandBase):
         dest="fmt",
     )
     @CommandArgument("paths", nargs="+", help="Paths whose data to query")
-    def file_info_bugzilla(self, paths, rev=None, fmt=None):
+    def file_info_bugzilla(self, command_context, paths, rev=None, fmt=None):
         """Show Bugzilla component for a set of files.
 
         Given a requested set of files (which can be specified using
@@ -180,7 +180,7 @@ class MozbuildFileCommands(MachCommandBase):
         help="Output format",
     )
     @CommandArgument("paths", nargs="+", help="Paths whose data to query")
-    def file_info_missing_bugzilla(self, paths, rev=None, fmt=None):
+    def file_info_missing_bugzilla(self, command_context, paths, rev=None, fmt=None):
         missing = set()
 
         try:
@@ -207,7 +207,7 @@ class MozbuildFileCommands(MachCommandBase):
         "Perform Bugzilla metadata analysis as required for automation",
     )
     @CommandArgument("out_dir", help="Where to write files")
-    def bugzilla_automation(self, out_dir):
+    def bugzilla_automation(self, command_context, out_dir):
         """Analyze and validate Bugzilla metadata as required by automation.
 
         This will write out JSON and gzipped JSON files for Bugzilla metadata.
@@ -337,7 +337,7 @@ class MozbuildFileCommands(MachCommandBase):
         "file-info", "schedules", "Show the combined SCHEDULES for the files listed."
     )
     @CommandArgument("paths", nargs="+", help="Paths whose data to query")
-    def file_info_schedules(self, paths):
+    def file_info_schedules(self, command_context, paths):
         """Show what is scheduled by the given files.
 
         Given a requested set of files (which can be specified using
diff --git a/python/mozbuild/mozbuild/mach_commands.py b/python/mozbuild/mozbuild/mach_commands.py
index d9432eff6842..aa34444b9b32 100644
--- a/python/mozbuild/mozbuild/mach_commands.py
+++ b/python/mozbuild/mozbuild/mach_commands.py
@@ -83,9 +83,8 @@ class Watch(MachCommandBase):
         action="store_true",
         help="Verbose output for what commands the watcher is running.",
     )
-    def watch(self, verbose=False):
+    def watch(self, command_context, verbose=False):
         """Watch and re-build (parts of) the source tree."""
-
         if not conditions.is_artifact_build(self):
             print(
                 "WARNING: mach watch only rebuilds the `mach build faster` parts of the tree!"
@@ -124,7 +123,7 @@ class CargoProvider(MachCommandBase):
     """Invoke cargo in useful ways."""
 
     @Command("cargo", category="build", description="Invoke cargo in useful ways.")
-    def cargo(self):
+    def cargo(self, command_context):
         self._sub_mach(["help", "cargo"])
         return 1
 
@@ -152,7 +151,9 @@ class CargoProvider(MachCommandBase):
         help="Run the tests in parallel using multiple processes.",
     )
     @CommandArgument("-v", "--verbose", action="store_true", help="Verbose output.")
-    def check(self, all_crates=None, crates=None, jobs=0, verbose=False):
+    def check(
+        self, command_context, all_crates=None, crates=None, jobs=0, verbose=False
+    ):
         # XXX duplication with `mach vendor rust`
         crates_and_roots = {
             "gkrust": "toolkit/library/rust",
@@ -208,7 +209,7 @@ class Doctor(MachCommandBase):
         action="store_true",
         help="Attempt to fix found problems.",
     )
-    def doctor(self, fix=None):
+    def doctor(self, command_context, fix=None):
         self.activate_virtualenv()
         from mozbuild.doctor import Doctor
 
@@ -234,7 +235,7 @@ class Clobber(MachCommandBase):
         "objdir and python).".format(", ".join(CLOBBER_CHOICES)),
     )
     @CommandArgument("--full", action="store_true", help="Perform a full clobber")
-    def clobber(self, what, full=False):
+    def clobber(self, command_context, what, full=False):
         """Clean up the source and object directories.
 
         Performing builds and running various commands generate various files.
@@ -357,7 +358,7 @@ class Logs(MachCommandBase):
         help="Filename to read log data from. Defaults to the log of the last "
         "mach command.",
     )
-    def show_log(self, log_file=None):
+    def show_log(self, command_context, log_file=None):
         if not log_file:
             path = self._get_state_filename("last_log.json")
             log_file = open(path, "rb")
@@ -446,7 +447,7 @@ class Warnings(MachCommandBase):
         help="Warnings report to display. If not defined, show the most "
         "recent report.",
     )
-    def summary(self, directory=None, report=None):
+    def summary(self, command_context, directory=None, report=None):
         database = self.database
 
         if directory:
@@ -487,7 +488,7 @@ class Warnings(MachCommandBase):
         help="Warnings report to display. If not defined, show the most "
         "recent report.",
     )
-    def list(self, directory=None, flags=None, report=None):
+    def list(self, command_context, directory=None, flags=None, report=None):
         database = self.database
 
         by_name = sorted(database.warnings)
@@ -645,6 +646,7 @@ class GTestCommands(MachCommandBase):
     )
     def gtest(
         self,
+        command_context,
         shuffle,
         jobs,
         gtest_filter,
@@ -876,7 +878,7 @@ class Package(MachCommandBase):
         action="store_true",
         help="Verbose output for what commands the packaging process is running.",
     )
-    def package(self, verbose=False):
+    def package(self, command_context, verbose=False):
         ret = self._run_make(
             directory=".", target="package", silent=not verbose, ensure_exit_code=False
         )
@@ -919,7 +921,7 @@ class Install(MachCommandBase):
         parser=setup_install_parser,
         description="Install the package on the machine (or device in the case of Android).",
     )
-    def install(self, **kwargs):
+    def install(self, command_context, **kwargs):
         if conditions.is_android(self):
             from mozrunner.devices.android_device import (
                 verify_android_device,
@@ -1228,7 +1230,7 @@ class RunProgram(MachCommandBase):
         parser=setup_run_parser,
         description="Run the compiled program, possibly under a debugger or DMD.",
     )
-    def run(self, **kwargs):
+    def run(self, command_context, **kwargs):
         if conditions.is_android(self):
             return self._run_android(**kwargs)
         if conditions.is_jsshell(self):
@@ -1838,7 +1840,7 @@ class Buildsymbols(MachCommandBase):
         category="post-build",
         description="Produce a package of Breakpad-format symbols.",
     )
-    def buildsymbols(self):
+    def buildsymbols(self, command_context):
         return self._run_make(
             directory=".", target="buildsymbols", ensure_exit_code=False
         )
@@ -1861,7 +1863,7 @@ class MachDebug(MachCommandBase):
     @CommandArgument(
         "--verbose", "-v", action="store_true", help="Print verbose output."
     )
-    def environment(self, format, output=None, verbose=False):
+    def environment(self, command_context, format, output=None, verbose=False):
         func = getattr(self, "_environment_%s" % format.replace(".", "_"))
 
         if output:
@@ -1968,7 +1970,7 @@ class Repackage(MachCommandBase):
     )
     @CommandArgument("--input", "-i", type=str, required=True, help="Input filename")
     @CommandArgument("--output", "-o", type=str, required=True, help="Output filename")
-    def repackage_dmg(self, input, output):
+    def repackage_dmg(self, command_context, input, output):
         if not os.path.exists(input):
             print("Input file does not exist: %s" % input)
             return 1
@@ -2022,7 +2024,15 @@ class Repackage(MachCommandBase):
         help="Run UPX on the self-extraction stub.",
     )
     def repackage_installer(
-        self, tag, setupexe, package, output, package_name, sfx_stub, use_upx
+        self,
+        command_context,
+        tag,
+        setupexe,
+        package,
+        output,
+        package_name,
+        sfx_stub,
+        use_upx,
     ):
         from mozbuild.repackaging.installer import repackage_installer
 
@@ -2065,7 +2075,16 @@ class Repackage(MachCommandBase):
     )
     @CommandArgument("--output", "-o", type=str, required=True, help="Output filename")
     def repackage_msi(
-        self, wsx, version, locale, arch, setupexe, candle, light, output
+        self,
+        command_context,
+        wsx,
+        version,
+        locale,
+        arch,
+        setupexe,
+        candle,
+        light,
+        output,
     ):
         from mozbuild.repackaging.msi import repackage_msi
 
@@ -2089,7 +2108,7 @@ class Repackage(MachCommandBase):
         "--arch", type=str, required=True, help="The archtecture you are building."
     )
     @CommandArgument("--mar-channel-id", type=str, help="Mar channel id")
-    def repackage_mar(self, input, mar, output, arch, mar_channel_id):
+    def repackage_mar(self, command_context, input, mar, output, arch, mar_channel_id):
         from mozbuild.repackaging.mar import repackage_mar
 
         repackage_mar(
@@ -2120,7 +2139,7 @@ class L10NCommands(MachCommandBase):
     @CommandArgument(
         "--verbose", action="store_true", help="Log informative status messages."
     )
-    def package_l10n(self, verbose=False, locales=[]):
+    def package_l10n(self, command_context, verbose=False, locales=[]):
         if "RecursiveMake" not in self.substs["BUILD_BACKENDS"]:
             print(
                 "Artifact builds do not support localization. "
@@ -2258,7 +2277,7 @@ class CreateMachEnvironment(MachCommandBase):
         action="store_true",
         help=("Force re-creating the virtualenv even if it is already " "up-to-date."),
     )
-    def create_mach_environment(self, force=False):
+    def create_mach_environment(self, command_context, force=False):
         from mozboot.util import get_mach_virtualenv_root
         from mozbuild.virtualenv import VirtualenvManager
 
diff --git a/python/mozbuild/mozbuild/vendor/mach_commands.py b/python/mozbuild/mozbuild/vendor/mach_commands.py
index 0818ba5af40f..67bff6e5717c 100644
--- a/python/mozbuild/mozbuild/vendor/mach_commands.py
+++ b/python/mozbuild/mozbuild/vendor/mach_commands.py
@@ -51,6 +51,7 @@ class Vendor(MachCommandBase):
     )
     def vendor(
         self,
+        command_context,
         library,
         revision,
         ignore_modified=False,
@@ -138,7 +139,7 @@ Please commit or stash these changes before vendoring, or re-run with `--ignore-
         ),
         default=False,
     )
-    def vendor_rust(self, **kwargs):
+    def vendor_rust(self, command_context, **kwargs):
         from mozbuild.vendor.vendor_rust import VendorRust
 
         vendor_command = self._spawn(VendorRust)
@@ -167,7 +168,7 @@ Please commit or stash these changes before vendoring, or re-run with `--ignore-
         "then Pipfile.lock will be regenerated. Note that transient dependencies "
         "may be updated when running this command.",
     )
-    def vendor_python(self, **kwargs):
+    def vendor_python(self, command_context, **kwargs):
         from mozbuild.vendor.vendor_python import VendorPython
 
         vendor_command = self._spawn(VendorPython)
diff --git a/python/mozperftest/mozperftest/mach_commands.py b/python/mozperftest/mozperftest/mach_commands.py
index 4651e02c5b9f..b0a93739a2de 100644
--- a/python/mozperftest/mozperftest/mach_commands.py
+++ b/python/mozperftest/mozperftest/mach_commands.py
@@ -42,7 +42,7 @@ class Perftest(MachCommandBase):
         description="Run any flavor of perftest",
         parser=get_perftest_parser,
     )
-    def run_perftest(self, **kwargs):
+    def run_perftest(self, command_context, **kwargs):
         # original parser that brought us there
         original_parser = self.get_parser()
 
@@ -185,7 +185,7 @@ class PerftestTests(MachCommandBase):
         default=False,
         help="Verbose mode",
     )
-    def run_tests(self, **kwargs):
+    def run_tests(self, command_context, **kwargs):
         MachCommandBase.activate_virtualenv(self)
 
         from pathlib import Path
diff --git a/python/mozperftest/mozperftest/tests/test_mach_commands.py b/python/mozperftest/mozperftest/tests/test_mach_commands.py
index 2975b47a9bdf..cb5de9e9e30d 100644
--- a/python/mozperftest/mozperftest/tests/test_mach_commands.py
+++ b/python/mozperftest/mozperftest/tests/test_mach_commands.py
@@ -61,9 +61,9 @@ def _get_command(klass=Perftest):
     # used to make arguments passed by the test as
     # being set by the user.
     def _run_perftest(func):
-        def _run(**kwargs):
+        def _run(command_context, **kwargs):
             parser.set_by_user = list(kwargs.keys())
-            return func(**kwargs)
+            return func(command_context, **kwargs)
 
         return _run
 
@@ -84,7 +84,7 @@ def _get_command(klass=Perftest):
 @mock.patch("mozperftest.mach_commands.MachCommandBase.activate_virtualenv")
 def test_command(mocked_func):
     with _get_command() as test, silence(test):
-        test.run_perftest(tests=[EXAMPLE_TEST], flavor="desktop-browser")
+        test.run_perftest(test, tests=[EXAMPLE_TEST], flavor="desktop-browser")
 
 
 @mock.patch("mozperftest.MachEnvironment")
@@ -96,7 +96,7 @@ def test_command_iterations(venv, env):
         "flavor": "desktop-browser",
     }
     with _get_command() as test, silence(test):
-        test.run_perftest(**kwargs)
+        test.run_perftest(test, **kwargs)
     # the hook changes the iteration value to 5.
     # each iteration generates 5 calls, so we want to see 25
     assert len(env.mock_calls) == 25
@@ -111,7 +111,7 @@ def test_hooks_state(venv, env):
         "flavor": "desktop-browser",
     }
     with _get_command() as test, silence(test):
-        test.run_perftest(**kwargs)
+        test.run_perftest(test, **kwargs)
 
 
 @mock.patch("mozperftest.MachEnvironment", new=_TestMachEnvironment)
@@ -120,6 +120,7 @@ def test_hooks_state(venv, env):
 def test_push_command(push_to_try, venv):
     with _get_command() as test, silence(test):
         test.run_perftest(
+            test,
             tests=[EXAMPLE_TEST],
             flavor="desktop-browser",
             push_to_try=True,
@@ -136,6 +137,7 @@ def test_push_command_unknown_platforms(push_to_try, venv):
     # full stop when a platform is unknown
     with _get_command() as test, pytest.raises(NotImplementedError):
         test.run_perftest(
+            test,
             tests=[EXAMPLE_TEST],
             flavor="desktop-browser",
             push_to_try=True,
@@ -149,6 +151,7 @@ def test_push_command_unknown_platforms(push_to_try, venv):
 def test_push_command_several_platforms(push_to_try, venv):
     with running_on_try(False), _get_command() as test:  # , silence(test):
         test.run_perftest(
+            test,
             tests=[EXAMPLE_TEST],
             flavor="desktop-browser",
             push_to_try=True,
@@ -165,7 +168,7 @@ def test_push_command_several_platforms(push_to_try, venv):
 @mock.patch("mozperftest.mach_commands.MachCommandBase.activate_virtualenv")
 def test_doc_flavor(mocked_func):
     with _get_command() as test, silence(test):
-        test.run_perftest(tests=[EXAMPLE_TEST], flavor="doc")
+        test.run_perftest(test, tests=[EXAMPLE_TEST], flavor="doc")
 
 
 @mock.patch("mozperftest.MachEnvironment", new=_TestMachEnvironment)
@@ -173,7 +176,7 @@ def test_doc_flavor(mocked_func):
 @mock.patch("mozperftest.utils.run_script")
 def test_test_runner(*mocked):
     with running_on_try(False), _get_command(PerftestTests) as test:
-        test.run_tests(tests=[EXAMPLE_TEST], verbose=True)
+        test.run_tests(test, tests=[EXAMPLE_TEST], verbose=True)
 
 
 @mock.patch("mozperftest.MachEnvironment", new=_TestMachEnvironment)
@@ -182,7 +185,7 @@ def test_test_runner(*mocked):
 def test_test_runner_on_try(*mocked):
     # simulating on try to run the paths parser
     with running_on_try(), _get_command(PerftestTests) as test:
-        test.run_tests(tests=[EXAMPLE_TEST])
+        test.run_tests(test, tests=[EXAMPLE_TEST])
 
 
 @mock.patch("mozperftest.MachEnvironment", new=_TestMachEnvironment)
@@ -194,7 +197,7 @@ def test_test_runner_coverage(*mocked):
         old = list(sys.meta_path)
         sys.meta_path = []
         try:
-            test.run_tests(tests=[EXAMPLE_TEST])
+            test.run_tests(test, tests=[EXAMPLE_TEST])
         finally:
             sys.meta_path = old
 
@@ -225,7 +228,7 @@ def resolve_tests(tests=None):
 @mock.patch("moztest.resolve.TestResolver.resolve_tests", new=resolve_tests())
 def test_fzf_flavor(*mocked):
     with running_on_try(False), _get_command() as test:  # , silence():
-        test.run_perftest(flavor="desktop-browser")
+        test.run_perftest(test, flavor="desktop-browser")
 
 
 @mock.patch("mozperftest.MachEnvironment", new=_TestMachEnvironment)
@@ -234,7 +237,7 @@ def test_fzf_flavor(*mocked):
 @mock.patch("moztest.resolve.TestResolver.resolve_tests", new=resolve_tests([]))
 def test_fzf_nothing_selected(*mocked):
     with running_on_try(False), _get_command() as test, silence():
-        test.run_perftest(flavor="desktop-browser")
+        test.run_perftest(test, flavor="desktop-browser")
 
 
 if __name__ == "__main__":
diff --git a/python/mozrelease/mozrelease/mach_commands.py b/python/mozrelease/mozrelease/mach_commands.py
index 14bda59489dd..de3320b66400 100644
--- a/python/mozrelease/mozrelease/mach_commands.py
+++ b/python/mozrelease/mozrelease/mach_commands.py
@@ -28,7 +28,7 @@ class MachCommands(MachCommandBase):
         category="release",
         description="Task that are part of the release process.",
     )
-    def release(self):
+    def release(self, command_context):
         """
         The release subcommands all relate to the release process.
         """
@@ -47,7 +47,7 @@ class MachCommands(MachCommandBase):
     @CommandArgument("--product", required=True, help="The product being built.")
     @CommandArgument("--repo", help="The repo being built.")
     @CommandArgument("--revision", required=True, help="The revision being built.")
-    def buglist(self, version, product, revision, repo):
+    def buglist(self, command_context, version, product, revision, repo):
         self.setup_logging()
         from mozrelease.buglist_creator import create_bugs_url
 
@@ -84,7 +84,7 @@ class MachCommands(MachCommandBase):
     @CommandArgument("--revision", required=True, help="The revision being built.")
     @CommandArgument("--build-number", required=True, help="The build number")
     @CommandArgument("--task-group-id", help="The task group of the build.")
-    def buglist_email(self, **options):
+    def buglist_email(self, command_context, **options):
         self.setup_logging()
         from mozrelease.buglist_creator import email_release_drivers
 
@@ -115,7 +115,9 @@ class MachCommands(MachCommandBase):
         required=False,
         help="Taskcluster secret with ssh-key to use for hg.mozilla.org",
     )
-    def push_scriptworker_canary(self, scriptworkers, addresses, ssh_key_secret):
+    def push_scriptworker_canary(
+        self, command_context, scriptworkers, addresses, ssh_key_secret
+    ):
         self.setup_logging()
         from mozrelease.scriptworker_canary import push_canary
 
diff --git a/remote/mach_commands.py b/remote/mach_commands.py
index 64a79217002c..b5a0bb4d530c 100644
--- a/remote/mach_commands.py
+++ b/remote/mach_commands.py
@@ -61,7 +61,7 @@ class RemoteCommands(MachCommandBase):
     @Command(
         "remote", category="misc", description="Remote protocol related operations."
     )
-    def remote(self):
+    def remote(self, command_context):
         """The remote subcommands all relate to the remote protocol."""
         self._sub_mach(["help", "remote"])
         return 1
@@ -88,7 +88,7 @@ class RemoteCommands(MachCommandBase):
         default=True,
         help="Do not install the just-pulled Puppeteer package,",
     )
-    def vendor_puppeteer(self, repository, commitish, install):
+    def vendor_puppeteer(self, command_context, repository, commitish, install):
         puppeteer_dir = os.path.join(self.remotedir, "test", "puppeteer")
 
         # Preserve our custom mocha reporter
@@ -587,6 +587,7 @@ class PuppeteerTest(MachCommandBase):
     )
     def puppeteer_test(
         self,
+        command_context,
         binary=None,
         ci=False,
         enable_fission=False,
diff --git a/taskcluster/mach_commands.py b/taskcluster/mach_commands.py
index e62c0151f1a3..aaf084b80692 100644
--- a/taskcluster/mach_commands.py
+++ b/taskcluster/mach_commands.py
@@ -339,7 +339,7 @@ class MachCommands(MachCommandBase):
         default=argparse.SUPPRESS,
         help="Kinds that should not be re-used from the on-push graph.",
     )
-    def taskgraph_decision(self, **options):
+    def taskgraph_decision(self, command_context, **options):
         """Run the decision task: generate a task graph and submit to
         TaskCluster.  This is only meant to be called within decision tasks,
         and requires a great many arguments.  Commands like `mach taskgraph
@@ -380,7 +380,7 @@ class MachCommands(MachCommandBase):
         "cron",
         description="Provide a pointer to the new `.cron.yml` handler.",
     )
-    def taskgraph_cron(self, **options):
+    def taskgraph_cron(self, command_context, **options):
         print(
             'Handling of ".cron.yml" files has move to '
             "https://hg.mozilla.org/ci/ci-admin/file/default/build-decision."
@@ -398,7 +398,7 @@ class MachCommands(MachCommandBase):
         default="taskcluster/ci",
         help="root of the taskgraph definition relative to topsrcdir",
     )
-    def action_callback(self, **options):
+    def action_callback(self, command_context, **options):
         from taskgraph.actions import trigger_action_callback
         from taskgraph.actions.util import get_parameters
 
@@ -456,7 +456,7 @@ class MachCommands(MachCommandBase):
     @CommandArgument(
         "callback", default=None, help="Action callback name (Python function name)"
     )
-    def test_action_callback(self, **options):
+    def test_action_callback(self, command_context, **options):
         import taskgraph.actions
         import taskgraph.parameters
         from taskgraph.util import yaml
@@ -714,7 +714,7 @@ class TaskClusterImagesProvider(MachCommandBase):
         "contents of the tree (as built for mozilla-central "
         "or mozilla-inbound)",
     )
-    def load_image(self, image_name, task_id, tag):
+    def load_image(self, command_context, image_name, task_id, tag):
         from taskgraph.docker import load_image_by_name, load_image_by_task_id
 
         if not image_name and not task_id:
@@ -744,7 +744,7 @@ class TaskClusterImagesProvider(MachCommandBase):
         "with this option it will only build the context.tar.",
         metavar="context.tar",
     )
-    def build_image(self, image_name, tag, context_only):
+    def build_image(self, command_context, image_name, tag, context_only):
         from taskgraph.docker import build_context, build_image
 
         try:
@@ -773,7 +773,7 @@ class TaskClusterPartialsData(MachCommandBase):
     @CommandArgument(
         "--product", default="Firefox", help="The product identifier, such as 'Firefox'"
     )
-    def generate_partials_builds(self, product, branch):
+    def generate_partials_builds(self, command_context, product, branch):
         from taskgraph.util.partials import populate_release_history
 
         try:
diff --git a/testing/awsy/mach_commands.py b/testing/awsy/mach_commands.py
index 1ca974bb0acc..ae9bd46c52bf 100644
--- a/testing/awsy/mach_commands.py
+++ b/testing/awsy/mach_commands.py
@@ -307,7 +307,7 @@ class MachCommands(MachCommandBase):
         default=False,
         help="Use the tp6 pageset during testing.",
     )
-    def run_awsy_test(self, tests, **kwargs):
+    def run_awsy_test(self, command_context, tests, **kwargs):
         """mach awsy-test runs the in-tree version of the Are We Slim Yet
         (AWSY) tests.
 
diff --git a/testing/condprofile/mach_commands.py b/testing/condprofile/mach_commands.py
index df70f1005fae..39fc17ff54e4 100644
--- a/testing/condprofile/mach_commands.py
+++ b/testing/condprofile/mach_commands.py
@@ -36,6 +36,7 @@ class CondprofileCommandProvider(MachCommandBase):
     )
     def fetch(
         self,
+        command_context,
         target_dir,
         platform,
         scenario,
@@ -88,7 +89,7 @@ class CondprofileCommandProvider(MachCommandBase):
         default=sys.platform.startswith("win") and "geckodriver.exe" or "geckodriver",
     )
     @CommandArgument("--device-name", help="Name of the device", type=str, default=None)
-    def run(self, **kw):
+    def run(self, command_context, **kw):
         os.environ["MANUAL_MACH_RUN"] = "1"
         self._init()
 
diff --git a/testing/firefox-ui/mach_commands.py b/testing/firefox-ui/mach_commands.py
index 56edef080eef..5b38d4127da3 100644
--- a/testing/firefox-ui/mach_commands.py
+++ b/testing/firefox-ui/mach_commands.py
@@ -98,7 +98,7 @@ class MachCommands(MachCommandBase):
         description="Run the functional test suite of Firefox UI tests.",
         parser=setup_argument_parser_functional,
     )
-    def run_firefox_ui_functional(self, **kwargs):
+    def run_firefox_ui_functional(self, command_context, **kwargs):
         try:
             kwargs["binary"] = kwargs["binary"] or self.get_binary_path("app")
         except BinaryNotFoundException as e:
diff --git a/testing/geckodriver/mach_commands.py b/testing/geckodriver/mach_commands.py
index bf5fe594e33d..ee55e61893f4 100644
--- a/testing/geckodriver/mach_commands.py
+++ b/testing/geckodriver/mach_commands.py
@@ -55,7 +55,7 @@ class GeckoDriver(MachCommandBase):
         help="Flags to pass to the debugger itself; "
         "split as the Bourne shell would.",
     )
-    def run(self, binary, params, debug, debugger, debugger_args):
+    def run(self, command_context, binary, params, debug, debugger, debugger_args):
         try:
             binpath = self.get_binary_path("geckodriver")
         except BinaryNotFoundException as e:
diff --git a/testing/gtest/mach_test_package_commands.py b/testing/gtest/mach_test_package_commands.py
index a837f070b644..d9ff70c2a261 100644
--- a/testing/gtest/mach_test_package_commands.py
+++ b/testing/gtest/mach_test_package_commands.py
@@ -127,7 +127,7 @@ class GtestCommands(MachCommandBase):
         description="Run the gtest harness.",
         parser=setup_argument_parser,
     )
-    def gtest(self, **kwargs):
+    def gtest(self, command_context, **kwargs):
         self._mach_context.activate_mozharness_venv()
         result = run_gtest(self._mach_context, **kwargs)
         return 0 if result else 1
diff --git a/testing/mach_commands.py b/testing/mach_commands.py
index da226e41e3ff..983f6f85f00b 100644
--- a/testing/mach_commands.py
+++ b/testing/mach_commands.py
@@ -170,6 +170,7 @@ class AddTest(MachCommandBase):
     )
     def addtest(
         self,
+        command_context,
         suite=None,
         test=None,
         doc=None,
@@ -351,7 +352,7 @@ class Test(MachCommandBase):
         description="Run tests (detects the kind of test and runs it).",
         parser=get_test_parser,
     )
-    def test(self, what, extra_args, **log_args):
+    def test(self, command_context, what, extra_args, **log_args):
         """Run tests from names or paths.
 
         mach test accepts arguments specifying which tests to run. Each argument
@@ -724,7 +725,9 @@ class CramTest(MachCommandBase):
         help="Extra arguments to pass down to the cram binary. See "
         "'./mach python -m cram -- -h' for a list of available options.",
     )
-    def cramtest(self, cram_args=None, test_paths=None, test_objects=None):
+    def cramtest(
+        self, command_context, cram_args=None, test_paths=None, test_objects=None
+    ):
         self.activate_virtualenv()
         import mozinfo
         from manifestparser import TestManifest
diff --git a/testing/marionette/mach_commands.py b/testing/marionette/mach_commands.py
index 8f3c009ff59b..7e9f57bd9488 100644
--- a/testing/marionette/mach_commands.py
+++ b/testing/marionette/mach_commands.py
@@ -72,7 +72,7 @@ class MarionetteTest(MachCommandBase):
         conditions=[functools.partial(conditions.is_buildapp_in, apps=SUPPORTED_APPS)],
         parser=create_parser_tests,
     )
-    def marionette_test(self, tests, **kwargs):
+    def marionette_test(self, command_context, tests, **kwargs):
         if "test_objects" in kwargs:
             tests = []
             for obj in kwargs["test_objects"]:
diff --git a/testing/marionette/mach_test_package_commands.py b/testing/marionette/mach_test_package_commands.py
index ad0328b2abda..0a13a1c2c8dc 100644
--- a/testing/marionette/mach_test_package_commands.py
+++ b/testing/marionette/mach_test_package_commands.py
@@ -70,6 +70,6 @@ class MachCommands(MachCommandBase):
         "using marionette).",
         parser=setup_marionette_argument_parser,
     )
-    def run_marionette_test(self, **kwargs):
+    def run_marionette_test(self, command_context, **kwargs):
         self.context.activate_mozharness_venv()
         return run_marionette(self.context, **kwargs)
diff --git a/testing/mochitest/mach_commands.py b/testing/mochitest/mach_commands.py
index 41458c179413..6f69128c8803 100644
--- a/testing/mochitest/mach_commands.py
+++ b/testing/mochitest/mach_commands.py
@@ -307,7 +307,12 @@ class MachCommands(MachCommandBase):
         parser=setup_argument_parser,
     )
     def run_mochitest_general(
-        self, flavor=None, test_objects=None, resolve_tests=True, **kwargs
+        self,
+        command_context,
+        flavor=None,
+        test_objects=None,
+        resolve_tests=True,
+        **kwargs
     ):
         from mochitest_options import ALL_FLAVORS
         from mozlog.commandline import setup_logging
@@ -531,7 +536,7 @@ class GeckoviewJunitCommands(MachCommandBase):
         action="store_true",
         default=False,
     )
-    def run_junit(self, no_install, **kwargs):
+    def run_junit(self, command_context, no_install, **kwargs):
         self._ensure_state_subdir_exists(".")
 
         from mozrunner.devices.android_device import (
diff --git a/testing/mochitest/mach_test_package_commands.py b/testing/mochitest/mach_test_package_commands.py
index 7ded92247d7e..20228cc20f09 100644
--- a/testing/mochitest/mach_test_package_commands.py
+++ b/testing/mochitest/mach_test_package_commands.py
@@ -201,7 +201,7 @@ class MochitestCommands(MachCommandBase):
         description="Run the mochitest harness.",
         parser=setup_mochitest_argument_parser,
     )
-    def mochitest(self, **kwargs):
+    def mochitest(self, command_context, **kwargs):
         self._mach_context.activate_mozharness_venv()
         return run_test(self._mach_context, False, **kwargs)
 
@@ -211,6 +211,6 @@ class MochitestCommands(MachCommandBase):
         description="Run the geckoview-junit harness.",
         parser=setup_junit_argument_parser,
     )
-    def geckoview_junit(self, **kwargs):
+    def geckoview_junit(self, command_context, **kwargs):
         self._mach_context.activate_mozharness_venv()
         return run_test(self._mach_context, True, **kwargs)
diff --git a/testing/mozharness/mach_commands.py b/testing/mozharness/mach_commands.py
index 5f1c0994a415..c1938cbbfa10 100644
--- a/testing/mozharness/mach_commands.py
+++ b/testing/mozharness/mach_commands.py
@@ -216,6 +216,6 @@ class MozharnessCommands(MachCommandBase):
         conditions=[conditions.is_firefox_or_android],
         parser=get_parser,
     )
-    def mozharness(self, **kwargs):
+    def mozharness(self, command_context, **kwargs):
         runner = self._spawn(MozharnessRunner)
         return runner.run_suite(kwargs.pop("suite_name")[0], **kwargs)
diff --git a/testing/raptor/mach_commands.py b/testing/raptor/mach_commands.py
index d2b63cdac35f..d94c0459bfb3 100644
--- a/testing/raptor/mach_commands.py
+++ b/testing/raptor/mach_commands.py
@@ -305,7 +305,7 @@ class MachRaptor(MachCommandBase):
         description="Run Raptor performance tests.",
         parser=create_parser,
     )
-    def run_raptor(self, **kwargs):
+    def run_raptor(self, command_context, **kwargs):
         # Defers this import so that a transitive dependency doesn't
         # stop |mach bootstrap| from running
         from raptor.power import enable_charging, disable_charging
@@ -381,5 +381,5 @@ class MachRaptor(MachCommandBase):
         description="Run Raptor performance tests.",
         parser=create_parser,
     )
-    def run_raptor_test(self, **kwargs):
+    def run_raptor_test(self, command_context, **kwargs):
         return self.run_raptor(**kwargs)
diff --git a/testing/talos/mach_commands.py b/testing/talos/mach_commands.py
index 3ac68f11f863..bd0b19673f98 100644
--- a/testing/talos/mach_commands.py
+++ b/testing/talos/mach_commands.py
@@ -131,7 +131,7 @@ class MachCommands(MachCommandBase):
         description="Run talos tests (performance testing).",
         parser=create_parser,
     )
-    def run_talos_test(self, **kwargs):
+    def run_talos_test(self, command_context, **kwargs):
         talos = self._spawn(TalosRunner)
 
         try:
diff --git a/testing/tps/mach_commands.py b/testing/tps/mach_commands.py
index d389cac4623a..4e25696aecef 100644
--- a/testing/tps/mach_commands.py
+++ b/testing/tps/mach_commands.py
@@ -17,7 +17,7 @@ class MachCommands(MachCommandBase):
 
     @Command("tps-build", category="testing", description="Build TPS add-on.")
     @CommandArgument("--dest", default=None, help="Where to write add-on.")
-    def build(self, dest):
+    def build(self, command_context, dest):
         src = os.path.join(
             self.topsrcdir, "services", "sync", "tps", "extensions", "tps"
         )
diff --git a/testing/web-platform/mach_commands.py b/testing/web-platform/mach_commands.py
index 333425c16bf9..478f1352fa9e 100644
--- a/testing/web-platform/mach_commands.py
+++ b/testing/web-platform/mach_commands.py
@@ -480,7 +480,7 @@ class MachCommands(MachCommandBase):
         description="Run web-platform-tests.",
         parser=create_parser_wpt,
     )
-    def run_web_platform_tests(self, **params):
+    def run_web_platform_tests(self, command_context, **params):
         self.setup()
         if params["product"] is None:
             if conditions.is_android(self):
@@ -523,7 +523,7 @@ class MachCommands(MachCommandBase):
         description="Run web-platform-tests.",
         parser=create_parser_wpt,
     )
-    def run_wpt(self, **params):
+    def run_wpt(self, command_context, **params):
         return self.run_web_platform_tests(**params)
 
     @Command(
@@ -532,7 +532,7 @@ class MachCommands(MachCommandBase):
         description="Update web-platform-test metadata.",
         parser=create_parser_update,
     )
-    def update_web_platform_tests(self, **params):
+    def update_web_platform_tests(self, command_context, **params):
         self.setup()
         self.virtualenv_manager.install_pip_package("html5lib==1.0.1")
         self.virtualenv_manager.install_pip_package("ujson")
@@ -548,7 +548,7 @@ class MachCommands(MachCommandBase):
         description="Update web-platform-test metadata.",
         parser=create_parser_update,
     )
-    def update_wpt(self, **params):
+    def update_wpt(self, command_context, **params):
         return self.update_web_platform_tests(**params)
 
     @Command(
@@ -557,7 +557,7 @@ class MachCommands(MachCommandBase):
         description="Update web-platform-test manifests.",
         parser=create_parser_manifest_update,
     )
-    def wpt_manifest_update(self, **params):
+    def wpt_manifest_update(self, command_context, **params):
         self.setup()
         wpt_setup = self._spawn(WebPlatformTestsRunnerSetup)
         wpt_runner = WebPlatformTestsRunner(wpt_setup)
@@ -574,7 +574,7 @@ class MachCommands(MachCommandBase):
         description="Run the wpt server",
         parser=create_parser_serve,
     )
-    def wpt_serve(self, **params):
+    def wpt_serve(self, command_context, **params):
         self.setup()
         import logging
 
@@ -589,7 +589,7 @@ class MachCommands(MachCommandBase):
         description="Create a json summary of the wpt metadata",
         parser=create_parser_metadata_summary,
     )
-    def wpt_summary(self, **params):
+    def wpt_summary(self, command_context, **params):
         import metasummary
 
         wpt_setup = self._spawn(WebPlatformTestsRunnerSetup)
@@ -598,7 +598,7 @@ class MachCommands(MachCommandBase):
     @Command(
         "wpt-metadata-merge", category="testing", parser=create_parser_metadata_merge
     )
-    def wpt_meta_merge(self, **params):
+    def wpt_meta_merge(self, command_context, **params):
         import metamerge
 
         if params["dest"] is None:
@@ -611,7 +611,7 @@ class MachCommands(MachCommandBase):
         description="Run the wpt tools and wptrunner unit tests",
         parser=create_parser_unittest,
     )
-    def wpt_unittest(self, **params):
+    def wpt_unittest(self, command_context, **params):
         self.setup()
         self.virtualenv_manager.install_pip_package("tox")
         runner = self._spawn(WebPlatformTestsUnittestRunner)
@@ -623,7 +623,7 @@ class MachCommands(MachCommandBase):
         description="Get a mapping from test ids to files",
         parser=create_parser_testpaths,
     )
-    def wpt_test_paths(self, **params):
+    def wpt_test_paths(self, command_context, **params):
         runner = self._spawn(WebPlatformTestsTestPathsRunner)
         runner.run(**params)
         return 0
@@ -634,7 +634,7 @@ class MachCommands(MachCommandBase):
         description="Dump a list of fission-specific regressions",
         parser=create_parser_fission_regressions,
     )
-    def wpt_fission_regressions(self, **params):
+    def wpt_fission_regressions(self, command_context, **params):
         runner = self._spawn(WebPlatformTestsFissionRegressionsRunner)
         runner.run(**params)
         return 0
diff --git a/testing/web-platform/mach_test_package_commands.py b/testing/web-platform/mach_test_package_commands.py
index e64bc3b0a86b..d6b3815a279d 100644
--- a/testing/web-platform/mach_test_package_commands.py
+++ b/testing/web-platform/mach_test_package_commands.py
@@ -75,12 +75,12 @@ class WebPlatformTestsRunnerSetup(object):
 @CommandProvider
 class MachCommands(MachCommandBase):
     @Command("web-platform-tests", category="testing", parser=create_parser_wpt)
-    def run_web_platform_tests(self, **kwargs):
+    def run_web_platform_tests(self, command_context, **kwargs):
         self._mach_context.activate_mozharness_venv()
         return WebPlatformTestsRunner(
             WebPlatformTestsRunnerSetup(self._mach_context)
         ).run(**kwargs)
 
     @Command("wpt", category="testing", parser=create_parser_wpt)
-    def run_wpt(self, **params):
+    def run_wpt(self, command_context, **params):
         return self.run_web_platform_tests(**params)
diff --git a/testing/xpcshell/mach_commands.py b/testing/xpcshell/mach_commands.py
index b7ec9c2e8561..60b2f3e9980e 100644
--- a/testing/xpcshell/mach_commands.py
+++ b/testing/xpcshell/mach_commands.py
@@ -228,7 +228,7 @@ class MachCommands(MachCommandBase):
         conditions=[lambda *args: True],
         parser=get_parser,
     )
-    def run_xpcshell_test(self, test_objects=None, **params):
+    def run_xpcshell_test(self, command_context, test_objects=None, **params):
         from mozbuild.controller.building import BuildDriver
 
         if test_objects is not None:
diff --git a/testing/xpcshell/mach_test_package_commands.py b/testing/xpcshell/mach_test_package_commands.py
index ba11d8160e22..f96219f37db9 100644
--- a/testing/xpcshell/mach_test_package_commands.py
+++ b/testing/xpcshell/mach_test_package_commands.py
@@ -60,6 +60,6 @@ class MochitestCommands(MachCommandBase):
         description="Run the xpcshell harness.",
         parser=parser_desktop,
     )
-    def xpcshell(self, **kwargs):
+    def xpcshell(self, command_context, **kwargs):
         self._mach_context.activate_mozharness_venv()
         return run_xpcshell(self._mach_context, **kwargs)
diff --git a/toolkit/components/telemetry/tests/marionette/mach_commands.py b/toolkit/components/telemetry/tests/marionette/mach_commands.py
index bc0129c180d1..90d3675f42c4 100644
--- a/toolkit/components/telemetry/tests/marionette/mach_commands.py
+++ b/toolkit/components/telemetry/tests/marionette/mach_commands.py
@@ -74,7 +74,7 @@ class TelemetryTest(MachCommandBase):
         conditions=[conditions.is_firefox_or_android],
         parser=create_parser_tests,
     )
-    def telemetry_test(self, tests, **kwargs):
+    def telemetry_test(self, command_context, tests, **kwargs):
         if "test_objects" in kwargs:
             tests = []
             for obj in kwargs["test_objects"]:
diff --git a/tools/browsertime/mach_commands.py b/tools/browsertime/mach_commands.py
index 489d87c13bc4..fdbae945238a 100644
--- a/tools/browsertime/mach_commands.py
+++ b/tools/browsertime/mach_commands.py
@@ -608,6 +608,7 @@ class MachBrowsertime(MachCommandBase):
     @CommandArgument("args", nargs=argparse.REMAINDER)
     def browsertime(
         self,
+        command_context,
         args,
         verbose=False,
         update_upstream_url="",
diff --git a/tools/compare-locales/mach_commands.py b/tools/compare-locales/mach_commands.py
index a8c1c901548a..f796e3ec5ce8 100644
--- a/tools/compare-locales/mach_commands.py
+++ b/tools/compare-locales/mach_commands.py
@@ -75,7 +75,7 @@ the output file, pass "-" to serialize to stdout and hide the default output.
     @CommandArgument(
         "--return-zero", action="store_true", help="Return 0 regardless of l10n status"
     )
-    def compare(self, **kwargs):
+    def compare(self, command_context, **kwargs):
         from compare_locales.commands import CompareLocales
 
         class ErrorHelper(object):
diff --git a/tools/lint/mach_commands.py b/tools/lint/mach_commands.py
index 4d48866b38a9..f5800b1c1e5e 100644
--- a/tools/lint/mach_commands.py
+++ b/tools/lint/mach_commands.py
@@ -69,7 +69,7 @@ class MachCommands(MachCommandBase):
         description="Run linters.",
         parser=setup_argument_parser,
     )
-    def lint(self, *runargs, **lintargs):
+    def lint(self, command_context, *runargs, **lintargs):
         """Run linters."""
         self.activate_virtualenv()
         from mozlint import cli, parser
@@ -124,7 +124,7 @@ class MachCommands(MachCommandBase):
         nargs=argparse.REMAINDER,
         help="Extra args that will be forwarded to eslint.",
     )
-    def eslint(self, paths, extra_args=[], **kwargs):
+    def eslint(self, command_context, paths, extra_args=[], **kwargs):
         self._mach_context.commands.dispatch(
             "lint",
             self._mach_context,
diff --git a/tools/mach_commands.py b/tools/mach_commands.py
index 3b340bf891fd..f3b47bf5f56f 100644
--- a/tools/mach_commands.py
+++ b/tools/mach_commands.py
@@ -38,7 +38,7 @@ class BustedProvider(MachCommandBase):
         category="misc",
         description="Query known bugs in our tooling, and file new ones.",
     )
-    def busted_default(self):
+    def busted_default(self, command_context):
         unresolved = _get_busted_bugs({"resolution": "---"})
         creation_time = datetime.now() - timedelta(days=15)
         creation_time = creation_time.strftime("%Y-%m-%dT%H-%M-%SZ")
@@ -72,7 +72,7 @@ class BustedProvider(MachCommandBase):
             "can also run `mach busted file general`."
         ),
     )
-    def busted_file(self, against):
+    def busted_file(self, command_context, against):
         import webbrowser
 
         if (
@@ -262,7 +262,9 @@ class PastebinProvider(MachCommandBase):
         default=None,
         help="Path to file for upload to paste.mozilla.org",
     )
-    def pastebin(self, list_highlighters, highlighter, expires, verbose, path):
+    def pastebin(
+        self, command_context, list_highlighters, highlighter, expires, verbose, path
+    ):
         import requests
 
         def verbose_print(*args, **kwargs):
@@ -436,7 +438,7 @@ class MozregressionCommand(MachCommandBase):
         description=("Regression range finder for nightly" " and inbound builds."),
         parser=mozregression_create_parser,
     )
-    def run(self, **options):
+    def run(self, command_context, **options):
         self.activate_virtualenv()
         mozregression = PypiBasedTool("mozregression")
         mozregression.run(**options)
@@ -450,7 +452,7 @@ class NodeCommands(MachCommandBase):
         description="Run the NodeJS interpreter used for building.",
     )
     @CommandArgument("args", nargs=argparse.REMAINDER)
-    def node(self, args):
+    def node(self, command_context, args):
         from mozbuild.nodeutil import find_node_executable
 
         # Avoid logging the command
@@ -470,7 +472,7 @@ class NodeCommands(MachCommandBase):
         description="Run the npm executable from the NodeJS used for building.",
     )
     @CommandArgument("args", nargs=argparse.REMAINDER)
-    def npm(self, args):
+    def npm(self, command_context, args):
         from mozbuild.nodeutil import find_npm_executable
 
         # Avoid logging the command
@@ -503,7 +505,7 @@ class LogspamCommand(MachCommandBase):
         category="misc",
         description=("Warning categorizer for treeherder test runs."),
     )
-    def logspam(self):
+    def logspam(self, command_context):
         pass
 
     @SubCommand("logspam", "report", parser=partial(logspam_create_parser, "report"))
diff --git a/tools/moztreedocs/mach_commands.py b/tools/moztreedocs/mach_commands.py
index a8597690179d..406feff996c0 100644
--- a/tools/moztreedocs/mach_commands.py
+++ b/tools/moztreedocs/mach_commands.py
@@ -107,6 +107,7 @@ class Documentation(MachCommandBase):
     )
     def build_docs(
         self,
+        command_context,
         path=None,
         fmt="html",
         outdir=None,
@@ -390,7 +391,7 @@ class Documentation(MachCommandBase):
         "mach-telemetry",
         description="Generate documentation from Glean metrics.yaml files",
     )
-    def generate_telemetry_docs(self):
+    def generate_telemetry_docs(self, command_context):
         args = [
             sys.executable,
             "-m" "glean_parser",
diff --git a/tools/phabricator/mach_commands.py b/tools/phabricator/mach_commands.py
index 532a6f4a0dcb..58c64122993f 100644
--- a/tools/phabricator/mach_commands.py
+++ b/tools/phabricator/mach_commands.py
@@ -22,7 +22,7 @@ class PhabricatorCommandProvider(MachCommandBase):
         action="store_true",
         help="Force installation even if already installed.",
     )
-    def install_moz_phab(self, force=False):
+    def install_moz_phab(self, command_context, force=False):
         import logging
         import os
         import re
diff --git a/tools/power/mach_commands.py b/tools/power/mach_commands.py
index 19e27874be41..bce8ea5b3bf6 100644
--- a/tools/power/mach_commands.py
+++ b/tools/power/mach_commands.py
@@ -42,7 +42,7 @@ class MachCommands(MachCommandBase):
         default=30000,
         help="The sample period, measured in milliseconds. Defaults to 30000.",
     )
-    def power(self, interval):
+    def power(self, command_context, interval):
         import os
         import re
         import subprocess
diff --git a/tools/tryselect/mach_commands.py b/tools/tryselect/mach_commands.py
index 1f5ed1547d7b..85b0f690be39 100644
--- a/tools/tryselect/mach_commands.py
+++ b/tools/tryselect/mach_commands.py
@@ -202,7 +202,7 @@ class TrySelect(MachCommandBase):
         description="Push selected tasks to the try server",
         parser=generic_parser,
     )
-    def try_default(self, argv=None, **kwargs):
+    def try_default(self, command_context, argv=None, **kwargs):
         """Push selected tests to the try server.
 
         The |mach try| command is a frontend for scheduling tasks to
@@ -234,7 +234,7 @@ class TrySelect(MachCommandBase):
         description="Select tasks on try using a fuzzy finder",
         parser=get_parser("fuzzy"),
     )
-    def try_fuzzy(self, **kwargs):
+    def try_fuzzy(self, command_context, **kwargs):
         """Select which tasks to run with a fuzzy finding interface (fzf).
 
         When entering the fzf interface you'll be confronted by two panes. The
@@ -337,7 +337,7 @@ class TrySelect(MachCommandBase):
         description="Schedule tasks by selecting them from a web " "interface.",
         parser=get_parser("chooser"),
     )
-    def try_chooser(self, **kwargs):
+    def try_chooser(self, command_context, **kwargs):
         """Push tasks selected from a web interface to try.
 
         This selector will build the taskgraph and spin up a dynamically
@@ -361,7 +361,7 @@ class TrySelect(MachCommandBase):
         "selector is EXPERIMENTAL.",
         parser=get_parser("auto"),
     )
-    def try_auto(self, **kwargs):
+    def try_auto(self, command_context, **kwargs):
         return self.run(**kwargs)
 
     @SubCommand(
@@ -370,7 +370,7 @@ class TrySelect(MachCommandBase):
         description="Schedule a previously generated (non try syntax) " "push again.",
         parser=get_parser("again"),
     )
-    def try_again(self, **kwargs):
+    def try_again(self, command_context, **kwargs):
         return self.run(**kwargs)
 
     @SubCommand(
@@ -379,7 +379,7 @@ class TrySelect(MachCommandBase):
         description="Push to try without scheduling any tasks.",
         parser=get_parser("empty"),
     )
-    def try_empty(self, **kwargs):
+    def try_empty(self, command_context, **kwargs):
         """Push to try, running no builds or tests
 
         This selector does not prompt you to run anything, it just pushes
@@ -396,7 +396,7 @@ class TrySelect(MachCommandBase):
         description="Select tasks on try using try syntax",
         parser=get_parser("syntax"),
     )
-    def try_syntax(self, **kwargs):
+    def try_syntax(self, command_context, **kwargs):
         """Push the current tree to try, with the specified syntax.
 
         Build options, platforms and regression tests may be selected
@@ -456,7 +456,7 @@ class TrySelect(MachCommandBase):
         description="Select tasks on try using coverage data",
         parser=get_parser("coverage"),
     )
-    def try_coverage(self, **kwargs):
+    def try_coverage(self, command_context, **kwargs):
         """Select which tasks to use using coverage data."""
         return self.run(**kwargs)
 
@@ -466,7 +466,7 @@ class TrySelect(MachCommandBase):
         description="Push the current tree to try, configured for a staging release.",
         parser=get_parser("release"),
     )
-    def try_release(self, **kwargs):
+    def try_release(self, command_context, **kwargs):
         """Push the current tree to try, configured for a staging release."""
         return self.run(**kwargs)
 
@@ -476,7 +476,7 @@ class TrySelect(MachCommandBase):
         description="Run scriptworker tasks against a recent release.",
         parser=get_parser("scriptworker"),
     )
-    def try_scriptworker(self, **kwargs):
+    def try_scriptworker(self, command_context, **kwargs):
         """Run scriptworker tasks against a recent release.
 
         Requires VPN and shipit access.
diff --git a/tools/vcs/mach_commands.py b/tools/vcs/mach_commands.py
index 0208399b857b..fb7bf111beb2 100644
--- a/tools/vcs/mach_commands.py
+++ b/tools/vcs/mach_commands.py
@@ -71,7 +71,12 @@ class PullRequestImporter(MachCommandBase):
         "https://github.com/servo/webrender/pull/3665).",
     )
     def import_pr(
-        self, pull_request, bug_number=None, bugzilla_token=None, reviewer=None
+        self,
+        command_context,
+        pull_request,
+        bug_number=None,
+        bugzilla_token=None,
+        reviewer=None,
     ):
         import requests