diff --git a/core/wasm_shims/python_c_api_probe_main.cc b/core/wasm_shims/python_c_api_probe_main.cc
new file mode 100644
index 0000000..508fa49
--- /dev/null
+++ b/core/wasm_shims/python_c_api_probe_main.cc
@@ -0,0 +1,73 @@
+#include "boost/python/object.hpp"
+
+#include <cstdlib>
+#include <cstring>
+
+// LinuxCNC source basis: src/emc/rs274ngc/gcodemodule.cc,
+// interpmodule.cc, and py*.cc use these Python C API entry points while
+// defining RS274 Python binding objects. The WASM shim keeps the API inert
+// and link-safe while browser Python execution remains disabled.
+namespace {
+
+struct ProbeObject {
+    PyObject_HEAD
+    int value;
+};
+
+} // namespace
+
+int main() {
+    if (Py_IsInitialized() != 1) {
+        return 1;
+    }
+    if (PyErr_Occurred() != nullptr) {
+        return 2;
+    }
+    PyObject *exc = reinterpret_cast<PyObject *>(1);
+    PyObject *val = reinterpret_cast<PyObject *>(1);
+    PyObject *tb = reinterpret_cast<PyObject *>(1);
+    PyErr_Fetch(&exc, &val, &tb);
+    if (exc || val || tb) {
+        return 3;
+    }
+    if (!Py_None || !Py_TYPE(Py_None) || std::strcmp(Py_TYPE(Py_None)->tp_name, "NoneType") != 0) {
+        return 4;
+    }
+    if (PyUnicode_FromString("linuxcnc") != Py_None) {
+        return 5;
+    }
+    if (std::strcmp(PyUnicode_AsUTF8(Py_None), "") != 0) {
+        return 6;
+    }
+    if (PyLong_FromLong(7) != Py_None || PyLong_AsLong(Py_None) != 0) {
+        return 7;
+    }
+    if (PyFloat_AsDouble(Py_None) != 0.0) {
+        return 8;
+    }
+    if (PyTuple_New(2) != Py_None || PyTuple_SetItem(Py_None, 0, Py_None) != 0 || PyTuple_Size(Py_None) != 0) {
+        return 9;
+    }
+    if (PyList_New(2) != Py_None || PyList_SetItem(Py_None, 0, Py_None) != 0 || PyList_Size(Py_None) != 0) {
+        return 10;
+    }
+    if (PyObject_IsTrue(Py_None) != 0 || PyCallable_Check(Py_None) != 0 || PyObject_IsInstance(Py_None, Py_None) != 0) {
+        return 11;
+    }
+    ProbeObject *probe = PyObject_New(ProbeObject, &PyList_Type);
+    if (!probe || Py_TYPE(reinterpret_cast<PyObject *>(probe)) != &PyList_Type) {
+        std::free(probe);
+        return 12;
+    }
+    std::free(probe);
+    if (PyModule_Create(nullptr) != Py_None || PyModule_AddObject(Py_None, "value", Py_None) != 0) {
+        return 13;
+    }
+    if (PyType_Ready(&PyList_Type) != 0 || PyType_GenericNew(&PyList_Type, Py_None, Py_None) != Py_None) {
+        return 14;
+    }
+    if (PyErr_Format(PyExc_TypeError, "linuxcnc") != nullptr) {
+        return 15;
+    }
+    return 0;
+}
diff --git a/test-linuxcnc-wasm-python-c-api-symbols.sh b/test-linuxcnc-wasm-python-c-api-symbols.sh
index f7a8b92..e7cab4d 100755
--- a/test-linuxcnc-wasm-python-c-api-symbols.sh
+++ b/test-linuxcnc-wasm-python-c-api-symbols.sh
@@ -70,6 +70,12 @@ object_sources=(
     "$python_c_api_shim"
     "$runtime_shim"
 )
+probe_objects=(
+    "$build_dir/python_c_api_probe_main.o"
+)
+probe_sources=(
+    core/wasm_shims/python_c_api_probe_main.cc
+)
 for source in "${python_binding_sources[@]}"; do
     object_name=$(basename "$source" .cc)
     objects+=("$build_dir/$object_name.o")
@@ -88,9 +94,11 @@ next_signature="$build_dir/python-c-api.signature.next"
     printf '\n'
     printf 'SOURCES:\n'
     printf '%s\n' "${object_sources[@]}"
+    printf 'PROBE_SOURCES:\n'
+    printf '%s\n' "${probe_sources[@]}"
 } > "$next_signature"
 if [[ ! -f "$signature" ]] || ! cmp -s "$signature" "$next_signature"; then
-    rm -f "$build_dir"/*.o "$build_dir"/*.d
+    rm -f "$build_dir"/*.o "$build_dir"/*.d "$build_dir/python_c_api_probe"
 fi
 mv "$next_signature" "$signature"
 
@@ -107,8 +115,11 @@ makefile="$build_dir/python-c-api.mk"
     for object in "${objects[@]}"; do
         printf 'DEP_FILES += %s.d\n' "$object"
     done
+    for object in "${probe_objects[@]}"; do
+        printf 'DEP_FILES += %s.d\n' "$object"
+    done
     printf '\n.PHONY: all\n'
-    printf 'all: $(OBJECTS)\n\n'
+    printf 'all: $(OBJECTS) %s\n\n' "$build_dir/python_c_api_probe"
 
     object_index=0
     for source in "${object_sources[@]}"; do
@@ -116,6 +127,14 @@ makefile="$build_dir/python-c-api.mk"
         printf '\t@$(CXX) $(COMMON_FLAGS) -MMD -MP -MF %s.d -c %s -o %s\n\n' "${objects[$object_index]}" "$source" "${objects[$object_index]}"
         object_index=$((object_index + 1))
     done
+    probe_index=0
+    for source in "${probe_sources[@]}"; do
+        printf '%s: %s\n' "${probe_objects[$probe_index]}" "$source"
+        printf '\t@$(CXX) $(COMMON_FLAGS) -MMD -MP -MF %s.d -c %s -o %s\n\n' "${probe_objects[$probe_index]}" "$source" "${probe_objects[$probe_index]}"
+        probe_index=$((probe_index + 1))
+    done
+    printf '%s: %s %s\n' "$build_dir/python_c_api_probe" "$build_dir/python_c_api_shim.o" "${probe_objects[*]}"
+    printf '\t@$(CXX) %s %s -o %s\n\n' "$build_dir/python_c_api_shim.o" "${probe_objects[*]}" "$build_dir/python_c_api_probe"
     printf '\n-include $(DEP_FILES)\n'
 } > "$makefile"
 make --output-sync=target -j"$build_jobs" -f "$makefile" >/dev/null
@@ -229,4 +248,6 @@ if [[ -s "$build_dir/object.missing-python" ]]; then
     exit 1
 fi
 
+"$build_dir/python_c_api_probe"
+
 echo "linuxcnc wasm Python C API symbol probe passed"