diff --git a/bin/Makefile b/bin/Makefile
index 993588d..8395138 100644
--- a/bin/Makefile
+++ b/bin/Makefile
@@ -1,7 +1,7 @@
 
 CFLAGS = -I/opt/local/include -Wall -DNDEBUG -O3 #-fomit-frame-pointer
 #CFLAGS = -I/opt/local/include -Wall -g
-LDFLAGS = -L/opt/local/lib -g -ldl -lgmp -rdynamic
+LDFLAGS = -L/opt/local/lib -g -ldl -lgmp #-rdynamic
 CC = gcc
 all: ikarus
 
diff --git a/bin/ikarus b/bin/ikarus
index 23c6933..f21510f 100755
Binary files a/bin/ikarus and b/bin/ikarus differ
diff --git a/bin/ikarus-collect.c b/bin/ikarus-collect.c
index 830a30a..6feb0ca 100644
--- a/bin/ikarus-collect.c
+++ b/bin/ikarus-collect.c
@@ -66,7 +66,6 @@ static unsigned int meta_mt[meta_count] = {
   pointers_mt
 };
 
-#define generation_count 5  /* generations 0 (nursery), 1, 2, 3, 4 */
 
 
 typedef struct{
@@ -243,6 +242,7 @@ static ikp add_object_proc(gc_t* gc, ikp x);
 
 static void collect_stack(gc_t*, ikp top, ikp base);
 static void collect_loop(gc_t*);
+static void guardians_loop(gc_t*);
 static void fix_weak_pointers(gc_t*);
 static void gc_add_tconcs(gc_t*);
 
@@ -320,8 +320,13 @@ ik_collect(int mem_req, ikpcb* pcb){
   pcb->arg_list = add_object(&gc, pcb->arg_list, "args_list_foo");
   /* now we trace all live objects */
   collect_loop(&gc);
+  
+  /* next we trace all guardian/guarded objects,
+     the procedure does a collect_loop at the end */
+  guardians_loop(&gc);
 
-  fix_weak_pointers(&gc);
+  /* does not allocate, only bwp's dead pointers */
+  fix_weak_pointers(&gc); 
   /* now deallocate all unused pages */
   deallocate_unused_pages(&gc);
 
@@ -412,46 +417,17 @@ ik_collect(int mem_req, ikpcb* pcb){
   return pcb;
 }
 
+static void  
+guardians_loop(gc_t* gc){
 
+
+}
 #define disp_frame_offset -13
 #define disp_multivalue_rp -9
 
 
 #define CODE_EXTENSION_SIZE (pagesize)
 
-//X static ikp
-//X gc_alloc_new_code_extending(int size, int old_gen, gc_t* gc){
-//X   int mapsize = align_to_next_page(size);
-//X   if(mapsize < CODE_EXTENSION_SIZE){
-//X     mapsize = CODE_EXTENSION_SIZE;
-//X   }
-//X   if(gc->gen[old_gen].code_base){
-//X     qupages_t* p = ik_malloc(sizeof(qupages_t));
-//X     ikp aq = gc->gen[old_gen].code_aq;
-//X     ikp ap = gc->gen[old_gen].code_ap;
-//X     ikp ep = gc->gen[old_gen].code_ep;
-//X     p->p = aq;
-//X     p->q = ap;
-//X     p->next = gc->code_queue;
-//X     gc->code_queue = p;
-//X     ikp x = ap;
-//X     while(x < ep){
-//X       ref(x, 0) = 0;
-//X       x += wordsize;
-//X     }
-//X   }
-//X   ikp mem = ik_mmap_typed(
-//X       mapsize, 
-//X       code_mt | next_gen_tag[old_gen],
-//X       gc->pcb);
-//X   gc->segment_vector = gc->pcb->segment_vector;
-//X   gc->gen[old_gen].code_ap = mem + size;
-//X   gc->gen[old_gen].code_aq = mem;
-//X   gc->gen[old_gen].code_ep = mem + mapsize;
-//X   gc->gen[old_gen].code_base = mem;
-//X   return mem;
-//X }
-//X 
 static int alloc_code_count = 0;
 
 
diff --git a/bin/ikarus-runtime.c b/bin/ikarus-runtime.c
index 4d195be..e02d01c 100644
--- a/bin/ikarus-runtime.c
+++ b/bin/ikarus-runtime.c
@@ -821,3 +821,27 @@ ikrt_write_char(){
   fprintf(stderr, "ikrt_write_char\n");
   return void_object;
 }
+
+
+
+ikp 
+ikrt_register_guardian(ikp tc, ikp obj, ikpcb* pcb){
+  ik_guardian_table* g = pcb->guardians[0];
+  if((!g) || (g->count == ik_guardian_table_size)){
+    if(sizeof(ik_guardian_table) != pagesize){
+      fprintf(stderr, "ERR: invaldi guardian table size\n");
+      exit(-1);
+    }
+    ik_guardian_table* p = 
+      (ik_guardian_table*)ik_alloc(pcb, sizeof(ik_guardian_table));
+    p->next = g;
+    p->count = 0;
+    pcb->guardians[0] = p;
+    g=p;
+  } 
+  ik_guardian_pair* p = &(g->p[g->count]);
+  p->tc = tc;
+  p->obj = obj;
+  g->count++;
+  return 0;
+}
diff --git a/bin/ikarus.h b/bin/ikarus.h
index 0c98416..56bc56d 100644
--- a/bin/ikarus.h
+++ b/bin/ikarus.h
@@ -59,6 +59,11 @@ inthash(int key) {
 
 
 
+#define wordsize 4
+#define wordshift 2
+#define pagesize 4096
+#define generation_count 5  /* generations 0 (nursery), 1, 2, 3, 4 */
+
 typedef unsigned char* ikp;
 void ik_error(ikp args);
 
@@ -78,6 +83,20 @@ typedef struct ikdl{ /* double-link */
   struct ikdl* next;
 } ikdl;
 
+typedef struct ik_guardian_pair{
+  ikp tc;
+  ikp obj;
+} ik_guardian_pair;
+
+#define ik_guardian_table_size \
+  ((pagesize - sizeof(int) - sizeof(struct ik_guardian_table*))/sizeof(ik_guardian_pair))
+
+typedef struct ik_guardian_table{
+  int count;
+  struct ik_guardian_table* next;
+  ik_guardian_pair p[ik_guardian_table_size];
+} ik_guardian_table;
+  
 
 typedef struct {
   /* the first locations may be accessed by some     */
@@ -104,6 +123,7 @@ typedef struct {
   ikp   stack_base;
   int   stack_size;
   ikp   oblist;
+  ik_guardian_table* guardians[generation_count];
   unsigned int* dirty_vector_base;
   unsigned int* segment_vector_base;
   unsigned char* memory_base;
@@ -147,9 +167,6 @@ ikp ik_asm_reenter(ikpcb*, ikp code_object, ikp val);
 ikp ik_underflow_handler(ikpcb*);
 ikp ik_alloc(ikpcb* pcb, int size);
 #include "ikarus-data.h"
-#define wordsize 4
-#define wordshift 2
-#define pagesize 4096
 #define ik_eof_p(x) ((x) == ik_eof_object)
 #define page_index(x) (((unsigned int)(x)) >> pageshift)
 
diff --git a/lab/optimize-gc.txt b/lab/optimize-gc.txt
index 870a53d..9a0278a 100644
--- a/lab/optimize-gc.txt
+++ b/lab/optimize-gc.txt
@@ -17,3 +17,6 @@ Copyright (c) 2006 Abdulaziz Ghuloum
 > 
         4.23 real         3.23 user         1.00 sys
 
+As of r127:
+        3.79 real         3.15 user         0.63 sys
+