diff --color -Naur a/configure b/configure
--- a/configure	2025-02-22 17:51:50
+++ b/configure	2025-02-22 17:52:18
@@ -32135,7 +32135,7 @@
     # isn't great, so it's disabled on ARM64.
     { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for HACL* SIMD128 implementation" >&5
 printf %s "checking for HACL* SIMD128 implementation... " >&6; }
-    if test "$UNIVERSAL_ARCHS" == "universal2"; then
+    if [[ "$build_cpu" == "aarch64" && "$build_vendor" == "apple" ]]; then
       LIBHACL_SIMD128_OBJS="Modules/_hacl/Hacl_Hash_Blake2s_Simd128_universal2.o"
       { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: universal2" >&5
 printf "%s\n" "universal2" >&6; }
@@ -32210,7 +32210,7 @@
     # wrapped implementation if we're building for universal2.
     { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for HACL* SIMD256 implementation" >&5
 printf %s "checking for HACL* SIMD256 implementation... " >&6; }
-    if test "$UNIVERSAL_ARCHS" == "universal2"; then
+    if [[ "$build_cpu" == "aarch64" && "$build_vendor" == "apple" ]]; then
       LIBHACL_SIMD256_OBJS="Modules/_hacl/Hacl_Hash_Blake2b_Simd256_universal2.o"
       { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: universal2" >&5
 printf "%s\n" "universal2" >&6; }
diff --color -Naur a/configure.ac b/configure.ac
--- a/configure.ac	2025-02-22 17:51:50
+++ b/configure.ac	2025-02-22 17:52:28
@@ -7869,7 +7869,7 @@
     # available on x86_64. However, performance of the HACL SIMD128 implementation
     # isn't great, so it's disabled on ARM64.
     AC_MSG_CHECKING([for HACL* SIMD128 implementation])
-    if test "$UNIVERSAL_ARCHS" == "universal2"; then
+    if [[ "$build_cpu" == "aarch64" && "$build_vendor" == "apple" ]]; then
       [LIBHACL_SIMD128_OBJS="Modules/_hacl/Hacl_Hash_Blake2s_Simd128_universal2.o"]
       AC_MSG_RESULT([universal2])
     else
@@ -7899,7 +7899,7 @@
     # implementation requires symbols that aren't available on ARM64. Use a
     # wrapped implementation if we're building for universal2.
     AC_MSG_CHECKING([for HACL* SIMD256 implementation])
-    if test "$UNIVERSAL_ARCHS" == "universal2"; then
+    if [[ "$build_cpu" == "aarch64" && "$build_vendor" == "apple" ]]; then
       [LIBHACL_SIMD256_OBJS="Modules/_hacl/Hacl_Hash_Blake2b_Simd256_universal2.o"]
       AC_MSG_RESULT([universal2])
     else