diff --git a/modules/modpython/CMakeLists.txt b/modules/modpython/CMakeLists.txt
index e65cc860..7184f42f 100644
--- a/modules/modpython/CMakeLists.txt
+++ b/modules/modpython/CMakeLists.txt
@@ -29,6 +29,17 @@ if(APPLE)
 endif()
 
 if(SWIG_FOUND)
+	set(SWIG_VERSION_HEADER "${CMAKE_CURRENT_BINARY_DIR}/swig_version.h")
+
+	add_custom_command(
+	    OUTPUT "${SWIG_VERSION_HEADER}"
+	    COMMAND ${CMAKE_COMMAND}
+	            -DSWIG_EXECUTABLE=${SWIG_EXECUTABLE}
+	            -DSWIG_VERSION_HEADER=${SWIG_VERSION_HEADER}
+	            -P "${CMAKE_CURRENT_SOURCE_DIR}/generate_swig_version.cmake"
+	    DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/generate_swig_version.cmake"
+	)
+
 	add_custom_command(
 		OUTPUT "pyfunctions.cpp"
 		COMMAND "${PERL_EXECUTABLE}"
@@ -36,7 +47,7 @@ if(SWIG_FOUND)
 		"${CMAKE_CURRENT_SOURCE_DIR}/functions.in"
 		"pyfunctions.cpp"
 		VERBATIM
-		DEPENDS codegen.pl functions.in)
+		DEPENDS codegen.pl functions.in "${SWIG_VERSION_HEADER}")
 
 	add_custom_command(
 		OUTPUT "swigpyrun.h"
@@ -98,7 +109,7 @@ endfunction()
 add_custom_target(modpython_dist
 	COMMAND "${CMAKE_COMMAND}" -E tar cz
 	"${CMAKE_CURRENT_SOURCE_DIR}/generated.tar.gz"
-	"swigpyrun.h" "znc_core.py" "modpython_biglib.cpp" "pyfunctions.cpp"
-	DEPENDS swigpyrun.h znc_core.py modpython_biglib.cpp pyfunctions.cpp
+	"swigpyrun.h" "znc_core.py" "modpython_biglib.cpp" "pyfunctions.cpp" "${SWIG_VERSION_HEADER}"
+	DEPENDS swigpyrun.h znc_core.py modpython_biglib.cpp pyfunctions.cpp "${SWIG_VERSION_HEADER}"
 	VERBATIM)
 add_dependencies(modpython_dist copy_csocket_h)
diff --git a/modules/modpython/codegen.pl b/modules/modpython/codegen.pl
index 1f01dd81..bbd8e2d5 100755
--- a/modules/modpython/codegen.pl
+++ b/modules/modpython/codegen.pl
@@ -49,6 +49,8 @@ print $out <<'EOF';
  * Don't change it manually.                                               *
  ***************************************************************************/
 
+#include "swig_version.h"
+
 namespace {
 	inline swig_type_info* ZNC_SWIG_pchar_descriptor(void) {
 		static int init = 0;
@@ -60,11 +62,8 @@ namespace {
 		return info;
 	}
 
-// SWIG 4.2.0 replaced SWIG_Python_str_AsChar with SWIG_PyUnicode_AsUTF8AndSize.
-// SWIG doesn't provide any good way to detect SWIG version (other than parsing
-// `swig -version`), but it also introduced SWIG_NULLPTR in 4.2.0.
-// So let's abuse that define to do different code for new SWIG.
-#ifdef SWIG_NULLPTR
+// SWIG_VERSION is defined as 0x040200 for 4.2.0.
+#if defined(SWIG_VERSION) && SWIG_VERSION >= 0x040200
 	// This is copied/adapted from SWIG 4.2.0 from pystrings.swg
 	inline int ZNC_SWIG_AsCharPtrAndSize(PyObject *obj, char** cptr, size_t* psize, int *alloc) {
 #if PY_VERSION_HEX>=0x03000000
diff --git a/modules/modpython/generate_swig_version.cmake b/modules/modpython/generate_swig_version.cmake
new file mode 100644
index 00000000..2d52501c
--- /dev/null
+++ b/modules/modpython/generate_swig_version.cmake
@@ -0,0 +1,53 @@
+# generate_swig_version.cmake
+execute_process(
+    COMMAND ${SWIG_EXECUTABLE} -version
+    OUTPUT_VARIABLE SWIG_OUTPUT
+    ERROR_VARIABLE SWIG_ERROR
+    OUTPUT_STRIP_TRAILING_WHITESPACE
+    ERROR_STRIP_TRAILING_WHITESPACE
+)
+
+set(FULL_OUTPUT "${SWIG_OUTPUT}\n${SWIG_ERROR}")
+
+string(REGEX MATCH "SWIG Version ([0-9]+)\\.([0-9]+)\\.([0-9]+)" MATCH_FOUND "${FULL_OUTPUT}")
+
+if(MATCH_FOUND)
+    # Extract capture groups
+    set(SWIG_VERSION_MAJOR ${CMAKE_MATCH_1})
+    set(SWIG_VERSION_MINOR ${CMAKE_MATCH_2})
+    set(SWIG_VERSION_PATCH ${CMAKE_MATCH_3})
+
+    message(STATUS "Found SWIG Version: ${SWIG_VERSION_MAJOR}.${SWIG_VERSION_MINOR}.${SWIG_VERSION_PATCH}")
+
+    # Format: 0x<MAJ><MIN><PATCH> (assuming 8 bits per component)
+    # Calculation: (Major << 16) | (Minor << 8) | Patch
+
+    math(EXPR VERSION_NUM
+        "(${SWIG_VERSION_MAJOR} << 16) + (${SWIG_VERSION_MINOR} << 8) + ${SWIG_VERSION_PATCH}"
+        OUTPUT_FORMAT HEXADECIMAL
+    )
+
+    set(HEADER_FILE "swig_version.h")
+
+    file(WRITE ${SWIG_VERSION_HEADER}
+"// Auto-generated by CMake
+#ifndef SWIG_VERSION_META_H
+#define SWIG_VERSION_META_H
+
+#define SWIG_VERSION_MAJOR ${SWIG_VERSION_MAJOR}
+#define SWIG_VERSION_MINOR ${SWIG_VERSION_MINOR}
+#define SWIG_VERSION_PATCH ${SWIG_VERSION_PATCH}
+
+// Hex format 0xMAJMINPAT (e.g. 4.1.0 -> 0x40100)
+#define SWIG_VERSION  ${VERSION_NUM}
+
+#endif // SWIG_VERSION_META_H
+"
+    )
+
+    message(STATUS "Generated ${HEADER_FILE} with version ${VERSION_NUM}")
+
+else()
+    message(WARNING "Could not parse SWIG version from output:\n${FULL_OUTPUT}")
+endif()
+