diff --git a/config.m4 b/config.m4
index 57fc2db..7270051 100644
--- a/config.m4
+++ b/config.m4
@@ -433,7 +433,6 @@
     third_party/boringssl/crypto/cpu-intel.c \
     third_party/boringssl/crypto/cpu-ppc64le.c \
     third_party/boringssl/crypto/crypto.c \
-    third_party/boringssl/crypto/curve25519/curve25519.c \
     third_party/boringssl/crypto/curve25519/spake25519.c \
     third_party/boringssl/crypto/curve25519/x25519-x86_64.c \
     third_party/boringssl/crypto/dh/check.c \
@@ -619,6 +618,7 @@
     third_party/boringssl/ssl/tls13_server.cc \
     third_party/boringssl/ssl/tls_method.cc \
     third_party/boringssl/ssl/tls_record.cc \
+    third_party/boringssl/third_party/fiat/curve25519.c \
     , $ext_shared, , -fvisibility=hidden \
     -DOPENSSL_NO_ASM -D_GNU_SOURCE -DWIN32_LEAN_AND_MEAN \
     -D_HAS_EXCEPTIONS=0 -DNOMINMAX -DGRPC_ARES=0)
@@ -726,5 +726,6 @@
   PHP_ADD_BUILD_DIR($ext_builddir/third_party/boringssl/crypto/x509)
   PHP_ADD_BUILD_DIR($ext_builddir/third_party/boringssl/crypto/x509v3)
   PHP_ADD_BUILD_DIR($ext_builddir/third_party/boringssl/ssl)
+  PHP_ADD_BUILD_DIR($ext_builddir/third_party/boringssl/third_party/fiat)
   PHP_ADD_BUILD_DIR($ext_builddir/third_party/nanopb)
 fi