diff --git a/fleetd/src/test/java/dev/ltms/fleet/session/GitWorktreesTest.java b/fleetd/src/test/java/dev/ltms/fleet/session/GitWorktreesTest.java
index 09e266e..971eeb6 100644
--- a/fleetd/src/test/java/dev/ltms/fleet/session/GitWorktreesTest.java
+++ b/fleetd/src/test/java/dev/ltms/fleet/session/GitWorktreesTest.java
@@ -1809,4 +1809,43 @@ class GitWorktreesTest {
                         + "different count means a helper now bypasses the hermetic factory; route "
                         + "it through gitProcessBuilder or document the new exception here");
     }
+
+    /**
+     * fleetd #369 review round 2. {@link #everyGitSubprocessGoesThroughTheHermeticFactory} counts
+     * call sites, not behaviour — it catches a NEW helper built the old, leak-prone way, but it
+     * cannot catch {@link #gitProcessBuilder} itself being gutted: deleting {@code
+     * pb.environment().putAll(hermeticEnv())} from inside the factory leaves every call site
+     * unchanged, the count stays 2, and the whole unpoisoned suite stays green — the exact leak
+     * this ticket fixed would come back silently, with nothing but a human remembering to re-run
+     * the poison command to catch it. This test instead inspects what the factory actually hands
+     * to {@link ProcessBuilder#start()}, so it fails the moment the hermetic environment stops
+     * being applied, on any machine, with no poison needed.
+     *
+     * <p>The property under test: every git subprocess this class starts must run with an
+     * environment that cannot see the operator's real git configuration. A call-site count is a
+     * proxy for that; this is the thing itself.
+     */
+    @Test
+    void gitProcessBuilderCarriesTheFullHermeticEnvironment(@TempDir Path tmp) {
+        Map<String, String> env = gitProcessBuilder(tmp, "status", "--porcelain").environment();
+
+        assertEquals("/dev/null", env.get("GIT_CONFIG_GLOBAL"),
+                "GIT_CONFIG_GLOBAL must be neutralized, or the operator's real ~/.gitconfig applies");
+        assertEquals("/dev/null", env.get("GIT_CONFIG_SYSTEM"),
+                "GIT_CONFIG_SYSTEM must be neutralized, or the machine's real /etc/gitconfig applies");
+        assertEquals("0", env.get("GIT_TERMINAL_PROMPT"),
+                "GIT_TERMINAL_PROMPT must be disabled, or a credential prompt can hang the subprocess");
+
+        String xdg = env.get("XDG_CONFIG_HOME");
+        assertNotNull(xdg,
+                "XDG_CONFIG_HOME must be set — left unset, git falls back to the operator's real "
+                        + "$HOME/.config/git/ignore (gitignore(5)), exactly fleetd #369's leak");
+        assertFalse(xdg.isBlank(), "XDG_CONFIG_HOME must not be blank — blank behaves like unset");
+        assertTrue(Path.of(xdg).startsWith(CLASS_TMP),
+                "XDG_CONFIG_HOME must point inside this test class's own throwaway directory, "
+                        + "never the operator's real one or the JVM's inherited value — got: " + xdg);
+        assertFalse(Files.exists(Path.of(xdg, "git", "ignore")),
+                "the resolved XDG default excludes file must provably not exist, or its contents "
+                        + "would silently apply to every git status this test class runs");
+    }
 }