diff --git a/src/backends/regex.c b/src/backends/regex.c
index 4b8db6e2eeb61b76d1ba2316f50e429c09343f92..659b2d935707950306439218c59a0173e30be1fe 100644
--- a/src/backends/regex.c
+++ b/src/backends/regex.c
@@ -147,7 +147,7 @@ void* h_rvm_run__m(HAllocator *mm__, HRVMProg *prog, const char* input, size_t l
 
   
   ret_trace = invert_trace(ret_trace);
-  HParseResult *ret = run_trace(ret_trace, input, length);
+  HParseResult *ret = run_trace(mm__, ret_trace, input, length);
   // ret is in its own arena
   h_delete_arena(arena);
   return ret;
@@ -167,3 +167,7 @@ HRVMTrace *invert_trace(HRVMTrace *trace) {
   } while (trace->next);
   return trace;
 }
+
+HParseResult *run_trace(HAllocator mm__, HRVMTrace *trace, uint8_t *input, int len) {
+  
+}