diff --git a/crypto/x509/by_file.c b/crypto/x509/by_file.c
index e6d0e6e1a6..b89456fd87 100644
--- a/crypto/x509/by_file.c
+++ b/crypto/x509/by_file.c
@@ -97,7 +97,10 @@ static int by_file_ctrl(X509_LOOKUP *ctx, int cmd, const char *argp,
     switch (cmd) {
     case X509_L_FILE_LOAD:
         if (argl == X509_FILETYPE_DEFAULT) {
-            file = ossl_safe_getenv(X509_get_default_cert_file_env());
+            file = ossl_safe_getenv("NIX_SSL_CERT_FILE");
+
+            if (!file)
+                file = ossl_safe_getenv(X509_get_default_cert_file_env());
 
             if (file)
                 ok = (X509_load_cert_crl_file(ctx, file,