diff --git a/ngxpp/NgxHeaders.hpp b/ngxpp/NgxHeaders.hpp
index 4a2be80..ecf21fe 100644
--- a/ngxpp/NgxHeaders.hpp
+++ b/ngxpp/NgxHeaders.hpp
@@ -59,6 +59,11 @@ class NgxHeaders final : public NgxWrapper<T>
 
         return p->value;
     }
+
+    ngx_str_t operator[](const char* key) const
+    {
+        return operator[](string_ref_type(key));
+    }
 public:
     void add(const kv_type& kv) const
     {