diff -r 07b815faa6ac -r f00d03835dd9 src/server/test/strreplace.c
--- a/src/server/test/strreplace.c	Tue Dec 30 21:44:49 2025 +0100
+++ b/src/server/test/strreplace.c	Tue Jan 13 18:09:20 2026 +0100
@@ -202,7 +202,7 @@
 }
 
 static cxmutstr get_var(const CxAllocator *a, StringTemplateSegment *seg, void *userdata, WSBool *free_str) {
-    cxmutstr var_value = cx_strcat_a(a, 3, cx_str("var("), seg->str, cx_str(")"));
+    cxmutstr var_value = cx_strcat_a(a, CX_NULLSTR, 3, cx_str("var("), seg->str, cx_str(")"));
     *free_str = TRUE;
     return var_value;
 }
@@ -212,7 +212,7 @@
     const CxAllocator *a = mp->allocator;
     
     CxBuffer buf;
-    cxBufferInit(&buf, NULL, 1024, a, CX_BUFFER_AUTO_EXTEND|CX_BUFFER_FREE_CONTENTS);
+    cxBufferInit(&buf, a, NULL, 1024, CX_BUFFER_AUTO_EXTEND|CX_BUFFER_FREE_CONTENTS);
     StringTemplate *tpl = NULL;
     CX_TEST_DO {
         tpl = string_template_compile(a, cx_str("hello world"));