diff --git a/.github/workflows/wheels.yml b/.github/workflows/wheels.yml
index f32fc3298..82c73e1d6 100644
--- a/.github/workflows/wheels.yml
+++ b/.github/workflows/wheels.yml
@@ -20,7 +20,7 @@ jobs:
       CIBW_BEFORE_ALL_LINUX: yum install -y swig || apk add swig
       CIBW_BEFORE_ALL_MACOS: brew install gnu-sed swig automake
       CIBW_BEFORE_ALL_WINDOWS: choco install swig --version=3.0.12 --no-progress --allow-downgrade -y
-      CIBW_BEFORE_BUILD_WINDOWS: .\tools\msvc\wheel_preamble.bat
+      CIBW_BEFORE_BUILD_WINDOWS: .\tools\msvc\swig.bat
       CIBW_REPAIR_WHEEL_COMMAND_LINUX: auditwheel repair --only-plat -w {dest_dir} {wheel}
       LIBWALLY_DIR: "."
       SWIG_PATH: "C:\\ProgramData\\chocolatey\\lib\\swig\\tools\\install\\swigwin-3.0.12"
diff --git a/configure.ac b/configure.ac
index 13a01cfa0..71fee02da 100644
--- a/configure.ac
+++ b/configure.ac
@@ -212,12 +212,6 @@ AC_RUN_IFELSE([AC_LANG_SOURCE([[int main(void){static int a[2];return *((int*)((
               have_unaligned=1, have_unaligned=0, have_unaligned=0)
 AC_DEFINE_UNQUOTED([HAVE_UNALIGNED_ACCESS], [$have_unaligned], [Define if we have unaligned access])
 
-if test "x$is_osx" != "xyes"; then
-    # Assume we are using gcc (i.e. have this attribute) if cross-compiling
-    AC_COMPILE_IFELSE([AC_LANG_SOURCE([extern int foo(int) __attribute__((weak)); int main(void){return 0;}])],
-                      [AC_DEFINE([HAVE_ATTRIBUTE_WEAK], 1, [Define if we have __attribute__((weak))])])
-fi
-
 AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <sys/mman.h>]],[[mmap(0,0,0,0,0,0)]])],
                [AC_DEFINE(HAVE_MMAP, 1, [Define if we have mmap])])
 
diff --git a/setup.py b/setup.py
index 5a92df4a0..c0249ea6a 100644
--- a/setup.py
+++ b/setup.py
@@ -77,7 +77,7 @@ def call(args, cwd=abs_path):
     include_dirs=include_dirs,
     extra_compile_args=extra_compile_args,
     sources=[
-        'src/swig_python/swig_wrap.c' if is_windows else 'src/swig_python/swig_python_wrap.c',
+        'src/swig_python/swig_python_wrap.c',
         'src/amalgamation/combined.c',
         'src/amalgamation/combined_ccan.c',
         'src/amalgamation/combined_ccan2.c',
diff --git a/src/amalgamation/windows_config/config.h b/src/amalgamation/windows_config/config.h
index 312345559..454a73eca 100644
--- a/src/amalgamation/windows_config/config.h
+++ b/src/amalgamation/windows_config/config.h
@@ -1,36 +1,19 @@
 #ifndef LIBWALLYCORE_CONFIG_H
 #define LIBWALLYCORE_CONFIG_H
+
+/* config.h for Windows. Assumes a little-endian intel-ish target */
 #include <stddef.h>
 
-#define HAVE_ATTRIBUTE_WEAK 1
-#define HAVE_BIG_ENDIAN 0
-#define HAVE_BSWAP_64 0
-#define HAVE_BYTESWAP_H 0
-#define HAVE_DLFCN_H 1
-#define HAVE_INTTYPES_H 1
-#define HAVE_LITTLE_ENDIAN 1
-#define HAVE_MEMORY_H 1
-#define HAVE_MMAP 1
-#define HAVE_PTHREAD 1
-#define HAVE_PTHREAD_PRIO_INHERIT 1
-#define HAVE_PYTHON "2.7"
-#define HAVE_STDINT_H 1
-#define HAVE_STDLIB_H 1
-#define HAVE_STRINGS_H 1
-#define HAVE_STRING_H 1
-#define HAVE_SYS_STAT_H 1
-#define HAVE_SYS_TYPES_H 1
-#define HAVE_UNISTD_H 1
-#define STDC_HEADERS 1
-#define VERSION "0.6"
-#if (!defined(_SSIZE_T_DECLARED)) && (!defined(_ssize_t)) && (!defined(ssize_t))
-#define ssize_t long long
+#ifndef _WIN32
+#error windows_config/config.h is only intended for windows builds
 #endif
 
-#define alignment_ok(p, n) ((size_t)(p) % (n) == 0)
+#define HAVE_UNALIGNED_ACCESS 1
 
-void wally_clear(void *p, size_t len);
+#if (!defined(_SSIZE_T_DECLARED)) && (!defined(_ssize_t)) && (!defined(ssize_t))
+#define ssize_t long long
+#endif
 
-#define CCAN_CLEAR_MEMORY(p, len) wally_clear(p, len)
+#include "ccan_config.h"
 
-#endif /*LIBWALLYCORE_CONFIG_H*/
+#endif /* LIBWALLYCORE_CONFIG_H */
diff --git a/tools/msvc/swig.bat b/tools/msvc/swig.bat
index 5cd57dfc9..56c7b668b 100644
--- a/tools/msvc/swig.bat
+++ b/tools/msvc/swig.bat
@@ -1,5 +1,5 @@
 REM You need to set SWIG_PATH to the location where the swig zip
 REM file is expanded to
-%SWIG_PATH%\swig -python -Isrc -I%SWIG_PATH%\Lib\python -DBUILD_ELEMENTS=1 src\swig_python\swig.i
+%SWIG_PATH%\swig -python -Isrc -I%SWIG_PATH%\Lib\python -DBUILD_ELEMENTS=1 src\swig_python\swig.i -o src\swig_python\swig_python_wrap.c
 copy src\swig_python\wallycore.py + src\swig_python\python_extra.py_in src\swig_python\wallycore\__init__.py /B
 del src\swig_python\wallycore.py