diff --git a/pyproject.toml b/pyproject.toml
index a930b8b..835ff80 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -172,11 +172,13 @@ fail_under = 79
 # https://github.com/wemake-services/coverage-conditional-plugin
 [tool.coverage.coverage_conditional_plugin.omit]
 "sys_platform != 'win32'" = [
-  "src/openjd/sessions/_linux/*.py",
   "src/openjd/sessions/_win32/*.py",
   "src/openjd/sessions/_scripts/_windows/*.py",
   "src/openjd/sessions/_windows*.py"
 ]
+"sys_platform == 'win32'" = [
+  "src/openjd/sessions/_linux/*.py",
+]
 
 [tool.coverage.coverage_conditional_plugin.rules]
 # This cannot be empty otherwise coverage-conditional-plugin crashes with:
diff --git a/src/openjd/sessions/_subprocess.py b/src/openjd/sessions/_subprocess.py
index e77fb20..cc70fb9 100644
--- a/src/openjd/sessions/_subprocess.py
+++ b/src/openjd/sessions/_subprocess.py
@@ -216,6 +216,9 @@ def _find_sudo_child_process_ids(
         *,
         timeout_seconds: float = 1,
     ) -> Optional[SudoChildProcessIDs]:
+        # Hint to mypy to not raise module attribute errors (e.g. missing os.getpgid)
+        if sys.platform == "win32":
+            raise NotImplementedError("This method is for POSIX hosts only")
         process = self._process
         if process is None:
             raise ValueError("Process not launched")
@@ -593,6 +596,10 @@ def _posix_signal_subprocess(
     ) -> None:
         """Send a given named signal to the subprocess."""
 
+        # Hint to mypy to not raise module attribute errors (e.g. missing os.getpgid)
+        if sys.platform == "win32":
+            raise NotImplementedError("This method is for POSIX hosts only")
+
         # We can run into a race condition where the process exits (and another thread sets self._process to None)
         # before the cancellation happens, so we swap to a local variable to ensure a cancellation that is not needed,
         # does not raise an exception here.
@@ -633,8 +640,7 @@ def _posix_signal_subprocess(
                     f"INTERRUPT: Unable to send {signal_name} to {process.pid}",
                     extra=LogExtraInfo(openjd_log_content=LogContent.PROCESS_CONTROL),
                 )
-            finally:
-                return
+            return
         elif signal_name == "kill":
             numeric_signal = signal.SIGKILL
         else:
diff --git a/testing_containers/localuser_sudo_environment/Dockerfile b/testing_containers/localuser_sudo_environment/Dockerfile
index d02f35e..3db697a 100644
--- a/testing_containers/localuser_sudo_environment/Dockerfile
+++ b/testing_containers/localuser_sudo_environment/Dockerfile
@@ -20,7 +20,7 @@ ENV PIP_INDEX_URL=$PIP_INDEX_URL
 #   hostuser: hostuser, sharedgroup
 #   targetuser: targetuser, sharedgroup
 #   disjointuser: disjointuser, disjointgroup
-RUN apt-get update && apt-get install -y sudo psmisc libcap2-bin libcap2 libcap-dev gcc && \
+RUN apt-get update && apt-get install -y libcap2-bin libcap2 libcap-dev gcc psmisc sudo && \
     # Clean up apt cache
     rm -rf /var/lib/apt/lists/* && \
     apt-get clean && \