diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 27c989d..da67ce5 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -87,7 +87,7 @@ jobs:
         with:
           postgres-version: 14
       - run: |
-          call "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Auxiliary\Build\vcvars64.bat" && ^
+          call "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Auxiliary\Build\vcvars32.bat" && ^
           nmake /NOLOGO /F Makefile.win && ^
           nmake /NOLOGO /F Makefile.win install && ^
           nmake /NOLOGO /F Makefile.win installcheck && ^
diff --git a/src/bitutils.h b/src/bitutils.h
index b4d85bb..14d67aa 100644
--- a/src/bitutils.h
+++ b/src/bitutils.h
@@ -8,6 +8,9 @@
 #error "Requires PostgreSQL 13+"
 #endif
 
+/* Check architecture in first header */
+StaticAssertDecl(sizeof(Datum) == SIZEOF_DATUM, "Architecture mismatch");
+
 extern uint64 (*BitHammingDistance) (uint32 bytes, unsigned char *ax, unsigned char *bx, uint64 distance);
 extern double (*BitJaccardDistance) (uint32 bytes, unsigned char *ax, unsigned char *bx, uint64 ab, uint64 aa, uint64 bb);