diff --git a/src/basic/assert-util.c b/src/basic/assert-util.c
index 87b760e8fe..0a068ee82d 100644
--- a/src/basic/assert-util.c
+++ b/src/basic/assert-util.c
@@ -4,40 +4,13 @@
 #include <stdlib.h>
 
 #include "assert-util.h"
-#include "env-util.h"
 #include "errno-util.h"
 #include "log.h"
 
-static bool assert_return_is_critical = BUILD_MODE_DEVELOPER;
-
 /* Akin to glibc's __abort_msg; which is private and we hence cannot
  * use here. */
 static char *log_abort_msg = NULL;
 
-void log_set_assert_return_is_critical(bool b) {
-        assert_return_is_critical = b;
-}
-
-void log_set_assert_return_is_critical_from_env(void) {
-        static int cached = INT_MIN;
-        int r;
-
-        if (cached == INT_MIN) {
-                r = secure_getenv_bool("SYSTEMD_ASSERT_RETURN_IS_CRITICAL");
-                if (r < 0 && r != -ENXIO)
-                        log_debug_errno(r, "Failed to parse $SYSTEMD_ASSERT_RETURN_IS_CRITICAL, ignoring: %m");
-
-                cached = r;
-        }
-
-        if (cached >= 0)
-                log_set_assert_return_is_critical(cached);
-}
-
-bool log_get_assert_return_is_critical(void) {
-        return assert_return_is_critical;
-}
-
 static void log_assert(
         int level,
         const char *text,
@@ -73,8 +46,8 @@ _noreturn_ void log_assert_failed_unreachable(const char *file, int line, const
 }
 
 void log_assert_failed_return(const char *text, const char *file, int line, const char *func) {
-
-        if (assert_return_is_critical)
+        /* log_get_assert_return_is_critical is a weak symbol. It may be NULL. */
+        if (log_get_assert_return_is_critical && log_get_assert_return_is_critical())
                 log_assert_failed(text, file, line, func);
 
         PROTECT_ERRNO;
diff --git a/src/basic/assert-util.h b/src/basic/assert-util.h
index fa3e13b220..899a436560 100644
--- a/src/basic/assert-util.h
+++ b/src/basic/assert-util.h
@@ -5,9 +5,7 @@
 
 /* Logging for various assertions */
 
-void log_set_assert_return_is_critical(bool b);
-void log_set_assert_return_is_critical_from_env(void);
-bool log_get_assert_return_is_critical(void) _pure_;
+bool log_get_assert_return_is_critical(void) _weak_ _pure_;
 
 void log_assert_failed_return(const char *text, const char *file, int line, const char *func);
 
diff --git a/src/fuzz/fuzz.h b/src/fuzz/fuzz.h
index a4cc7ab67d..be708abfd1 100644
--- a/src/fuzz/fuzz.h
+++ b/src/fuzz/fuzz.h
@@ -7,6 +7,7 @@
 
 #include "fileio.h"
 #include "log.h"
+#include "log-assert-critical.h"
 
 /* The entry point into the fuzzer */
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
diff --git a/src/shared/log-assert-critical.c b/src/shared/log-assert-critical.c
new file mode 100644
index 0000000000..e30dc7df49
--- /dev/null
+++ b/src/shared/log-assert-critical.c
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "env-util.h"
+#include "log.h"
+#include "log-assert-critical.h"
+
+static bool assert_return_is_critical = BUILD_MODE_DEVELOPER;
+
+void log_set_assert_return_is_critical(bool b) {
+        assert_return_is_critical = b;
+}
+
+void log_set_assert_return_is_critical_from_env(void) {
+        static int cached = INT_MIN;
+        int r;
+
+        if (cached == INT_MIN) {
+                r = secure_getenv_bool("SYSTEMD_ASSERT_RETURN_IS_CRITICAL");
+                if (r < 0 && r != -ENXIO)
+                        log_debug_errno(r, "Failed to parse $SYSTEMD_ASSERT_RETURN_IS_CRITICAL, ignoring: %m");
+
+                cached = r;
+        }
+
+        if (cached >= 0)
+                log_set_assert_return_is_critical(cached);
+}
+
+bool log_get_assert_return_is_critical(void) {
+        return assert_return_is_critical;
+}
diff --git a/src/shared/log-assert-critical.h b/src/shared/log-assert-critical.h
new file mode 100644
index 0000000000..62c7360412
--- /dev/null
+++ b/src/shared/log-assert-critical.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include "basic-forward.h"
+
+void log_set_assert_return_is_critical(bool b);
+void log_set_assert_return_is_critical_from_env(void);
diff --git a/src/shared/meson.build b/src/shared/meson.build
index 15763d4c65..38915f3885 100644
--- a/src/shared/meson.build
+++ b/src/shared/meson.build
@@ -119,6 +119,7 @@ shared_sources = files(
         'libmount-util.c',
         'local-addresses.c',
         'locale-setup.c',
+        'log-assert-critical.c',
         'logs-show.c',
         'loop-util.c',
         'loopback-setup.c',
diff --git a/src/shared/nss-util.c b/src/shared/nss-util.c
index 32a36cd57e..5a40c40a41 100644
--- a/src/shared/nss-util.c
+++ b/src/shared/nss-util.c
@@ -6,6 +6,7 @@
 
 #include "assert-util.h"
 #include "log.h"
+#include "log-assert-critical.h"
 #include "nss-util.h"
 
 sd_json_dispatch_flags_t nss_json_dispatch_flags = SD_JSON_ALLOW_EXTENSIONS;
diff --git a/src/shared/tests.h b/src/shared/tests.h
index 3f50b3dc54..a408fbd087 100644
--- a/src/shared/tests.h
+++ b/src/shared/tests.h
@@ -7,6 +7,7 @@
 #include "errno-util.h"
 #include "shared-forward.h"
 #include "log.h"
+#include "log-assert-critical.h"
 #include "static-destruct.h"
 #include "signal-util.h"
 #include "stdio-util.h"