diff --git a/runtime/main.c b/runtime/main.c
index a6cbf0b3..6b351a68 100644
--- a/runtime/main.c
+++ b/runtime/main.c
@@ -318,13 +318,17 @@ static int readable(uint64_t a, uint64_t n) { return plat_mem_readable(a, n); }
 // capture tool or a post-processing injector, by the words such files carry in their names. A crash inside one is that
 // program's: one report was an access violation in a recorder's layer the moment the present mode changed and the
 // swapchain was made again, another an injector's layer reading a null pointer at the end of every shader
-// preparation.
+// preparation. Vulkan layers are mostly named VkLayer_<name>.dll, and a recorder's Vulkan hook and a driver's capture
+// tool carry names of their own (the words below). The validation layer is left out: the game loads it itself when
+// NX2NAVI_VK_VALIDATION asks.
 static int foreign_hook(const char *module) {
     char low[160];
     size_t n = 0;
     for (; module && module[n] && n < sizeof low - 1; n++) low[n] = (char)tolower((unsigned char)module[n]);
     low[n] = 0;
-    return strstr(low, "vk_layer") || strstr(low, "hook") || strstr(low, "overlay") || strstr(low, "reshade");
+    if (strstr(low, "vklayer_khronos")) return 0;
+    return strstr(low, "vk_layer") || strstr(low, "vklayer") || strstr(low, "hook") || strstr(low, "overlay") ||
+           strstr(low, "reshade") || strstr(low, "obs-vulkan") || strstr(low, "nvspcap");
 }
 
 // Set when main_run has returned: the mode's work is done and saved, and all that still runs is the C runtime's exit
diff --git a/tests/foreign_hook_check.py b/tests/foreign_hook_check.py
new file mode 100644
index 00000000..097dcc99
--- /dev/null
+++ b/tests/foreign_hook_check.py
@@ -0,0 +1,72 @@
+"""The crash report's test for a module another program put into the game (runtime/main.c foreign_hook): the Vulkan
+layers, hooks and overlays of recorders, overlays and capture tools are named as theirs; the game's own libraries and
+the drivers are not, nor the validation layer the game loads itself (NX2NAVI_VK_VALIDATION). Builds foreign_hook, cut
+out of main.c, into a test program. No game files.
+
+Usage: python tests/foreign_hook_check.py [path to clang]"""
+import os
+import shutil
+import subprocess
+import sys
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[1]
+MSYS_BIN = Path(r'C:\msys64\ucrt64\bin')
+source = (ROOT / 'runtime' / 'main.c').read_text(encoding='utf-8')
+
+FOREIGN = ['RTSSHooks64.dll', 'graphics-hook64.dll', 'GameOverlayRenderer64.dll', 'ReShade64.dll',
+           'EOSOverlayVkLayer-Win64.dll', 'VkLayer_steam_fossilize64.dll', 'VkLayer_obs64.dll', 'obs-vulkan64.dll',
+           'nvspcap64.dll']
+OWN = ['VkLayer_khronos_validation.dll', 'amdvlk64.dll', 'nvoglv64.dll', 'nvngx_dlss.dll', 'ucrtbase.dll', 'SDL3.dll',
+       'amd_fidelityfx_vk.dll', 'ntdll.dll', 'nx2navi_dlssg.dll', '']
+
+
+def compiler():
+    if len(sys.argv) > 1:
+        return sys.argv[1]
+    if os.environ.get('CC'):
+        return os.environ['CC']
+    if os.name == 'nt' and (MSYS_BIN / 'clang.exe').exists():
+        return str(MSYS_BIN / 'clang.exe')
+    return shutil.which('clang') or 'clang'
+
+
+def function(signature):
+    start = source.index(signature)
+    brace = source.index('{', start)
+    depth, end = 1, brace + 1
+    while depth:
+        depth += (source[end] == '{') - (source[end] == '}')
+        end += 1
+    return source[start:end]
+
+
+def main():
+    names = FOREIGN + OWN
+    src = ('#include <ctype.h>\n#include <stdio.h>\n#include <string.h>\n' + function('static int foreign_hook(')
+           + '\nint main(int argc, char **argv) {\n    for (int i = 1; i < argc; i++) printf("%d\\n", foreign_hook(argv[i]));\n'
+           '    return 0;\n}\n')
+    work = ROOT / 'build' / 'test' / 'foreign_hook'
+    work.mkdir(parents=True, exist_ok=True)
+    (work / 'foreign_hook_check.c').write_text(src, encoding='utf-8')
+    exe = work / ('foreign_hook_check.exe' if os.name == 'nt' else 'foreign_hook_check')
+    env = dict(os.environ)
+    if os.name == 'nt' and MSYS_BIN.exists():
+        env['PATH'] = str(MSYS_BIN) + os.pathsep + env.get('PATH', '')
+    subprocess.check_call([compiler(), '-O1', '-Wall', str(work / 'foreign_hook_check.c'), '-o', str(exe)], env=env)
+    got = subprocess.run([str(exe), *names], env=env, capture_output=True, text=True, timeout=60).stdout.split()
+    bad = 0
+    for name, g in zip(names, got):
+        want = '1' if name in FOREIGN else '0'
+        if g != want:
+            bad += 1
+        print(f'{name or "(outside every module)"}: {"another program" if g == "1" else "not foreign"}'
+              f'{"" if g == want else " FAIL"}')
+    if len(got) != len(names):
+        bad += 1
+    print(f'foreign_hook_check: {"FAILED" if bad else "ok"}')
+    return 1 if bad else 0
+
+
+if __name__ == '__main__':
+    sys.exit(main())