diff --git a/H/Regs.h b/H/Regs.h
index e5c4208a1..344c8dc2e 100644
--- a/H/Regs.h
+++ b/H/Regs.h
@@ -92,7 +92,6 @@ INLINE_ONLY inline EXTERN void save_B(void);
 
 typedef struct regstore_t
   {
-    Int     CurSlot_;
     CELL    CreepFlag_;		/* 13                                         */
     CELL   *HB_;		/* 4 heap (global) stack top at latest c.p.   */
 #if defined(YAPOR_SBA) || defined(TABLING)
@@ -634,7 +633,6 @@ INLINE_ONLY EXTERN inline void restore_B(void) {
 
 #endif
 
-#define	CurSlot       Yap_REGS.CurSlot_
 #define	AuxBase       Yap_REGS.AuxBase_
 #define	AuxSp         Yap_REGS.AuxSp_
 #define	AuxTop        Yap_REGS.AuxTop_
diff --git a/H/Yap.h b/H/Yap.h
index f315677be..36ead420b 100755
--- a/H/Yap.h
+++ b/H/Yap.h
@@ -747,81 +747,7 @@ extern struct worker_local Yap_local;
 
 #include "YapCompoundTerm.h"
 
-
-
-/*************************************************************************************************
-                                           slots
-*************************************************************************************************/
-
-
-static inline void
-Yap_StartSlots( USES_REGS1 ) {
-  if (CurSlot == LCL0-ASP)
-    return;
-  *--ASP = MkIntegerTerm(CurSlot);
-  *--ASP = MkIntTerm(0);
-  CurSlot = LCL0-ASP;
-}
-
-/* pop slots when pruning */
-static inline void
-Yap_PopSlots( USES_REGS1 ) {
-  while (LCL0-CurSlot < ASP) {
-    Int old_slots;
-    CELL *ptr = LCL0-CurSlot;
-    old_slots = IntOfTerm(ptr[0]);
-    ptr += (old_slots+1);
-    CurSlot = IntOfTerm(*ptr);    
-  }
-}
-
-static inline void
-Yap_CloseSlots( USES_REGS1 ) {
-  Int old_slots;
-  Yap_PopSlots( PASS_REGS1 );
-  if (LCL0-CurSlot == ASP) {
-    old_slots = IntOfTerm(ASP[0]);
-    ASP += (old_slots+1);
-    CurSlot = IntOfTerm(*ASP);
-    ASP++;
-  }
-}
-
-static inline Int
-Yap_CurrentSlot( USES_REGS1 ) {
-  return IntOfTerm(ASP[0]);
-}
-
-static inline Term
-Yap_GetFromSlot(Int slot USES_REGS)
-{
-  return(Deref(LCL0[slot]));
-}
-
-static inline Term
-Yap_GetDerefedFromSlot(Int slot USES_REGS)
-{
-  return LCL0[slot];;
-}
-
-static inline Term
-Yap_GetPtrFromSlot(Int slot USES_REGS)
-{
-  return(LCL0[slot]);
-}
-
-static inline Term *
-Yap_AddressFromSlot(Int slot USES_REGS)
-{
-  return(LCL0+slot);
-}
-
-static inline void
-Yap_PutInSlot(Int slot, Term t USES_REGS)
-{
-  LCL0[slot] = t;
-}
-
+#include "YapHandles.h"
 
 #endif /* YAP_H */
 
diff --git a/H/Yapproto.h b/H/Yapproto.h
index 3f366fbe0..043dfbf52 100644
--- a/H/Yapproto.h
+++ b/H/Yapproto.h
@@ -55,9 +55,6 @@ Term	Yap_NWideStringToDiffListOfAtoms(wchar_t *, Term, size_t);
 int     Yap_AtomIncreaseHold(Atom);
 int     Yap_AtomDecreaseHold(Atom);
 struct operator_entry *Yap_OpPropForModule(Atom, Term);
-Int	Yap_InitSlot(Term CACHE_TYPE);
-Int     Yap_NewSlots(int CACHE_TYPE);
-int     Yap_RecoverSlots(int CACHE_TYPE);
 
 
 #ifdef SFUNC
diff --git a/H/cut_c.h b/H/cut_c.h
index 752f7b1fc..b1c7b0333 100644
--- a/H/cut_c.h
+++ b/H/cut_c.h
@@ -39,9 +39,7 @@ struct cut_c_str{
         cut_c_str_ptr TOP = Yap_REGS.CUT_C_TOP;                                            \
         CPredicate func = (CPredicate)((yamop *)TOP->try_userc_cut_yamop)->u.OtapFs.f;   \
         PredEntry *pred = (PredEntry *)((yamop *)TOP->try_userc_cut_yamop)->u.OtapFs.p;  \
-	Yap_StartSlots( PASS_REGS1 ); \
         YAP_ExecuteOnCut(pred, func, TOP); \
-	Yap_CloseSlots( PASS_REGS1 ); \
         cut_c_pop();
 
 
diff --git a/H/dhstruct.h b/H/dhstruct.h
index 62452cc40..72b9bf919 100644
--- a/H/dhstruct.h
+++ b/H/dhstruct.h
@@ -71,6 +71,7 @@
 #define LOCKPRED_OPCODE Yap_heap_regs->lockpred_op
 #define ORLAST_OPCODE Yap_heap_regs->orlast_op
 #define UNDEF_OPCODE Yap_heap_regs->undef_op
+#define RETRY_USERC_OPCODE Yap_heap_regs->retry_userc_op
 
 #define NOfAtoms Yap_heap_regs->n_of_atoms
 #define AtomHashTableSize Yap_heap_regs->atom_hash_table_size
diff --git a/H/dlocals.h b/H/dlocals.h
index 418fe3d62..3162fdc16 100644
--- a/H/dlocals.h
+++ b/H/dlocals.h
@@ -412,6 +412,9 @@
 
 #define LOCAL_search_atoms LOCAL->search_atoms_
 #define REMOTE_search_atoms(wid) REMOTE(wid)->search_atoms_
+
+#define LOCAL_CurSlot LOCAL->CurSlot_
+#define REMOTE_CurSlot(wid) REMOTE(wid)->CurSlot_
 #define LOCAL_SourceModule LOCAL->SourceModule_
 #define REMOTE_SourceModule(wid) REMOTE(wid)->SourceModule_
 
diff --git a/H/hlocals.h b/H/hlocals.h
index 4486c3a07..426c20b44 100644
--- a/H/hlocals.h
+++ b/H/hlocals.h
@@ -232,5 +232,7 @@ typedef struct worker_local {
   UInt  exo_arg_;
 
   struct scan_atoms*  search_atoms_;
+
+  Int  CurSlot_;
   Term  SourceModule_;
 } w_local;
diff --git a/H/hstruct.h b/H/hstruct.h
index d6a085603..be7d29a0b 100755
--- a/H/hstruct.h
+++ b/H/hstruct.h
@@ -71,6 +71,7 @@
   OPCODE  lockpred_op;
   OPCODE  orlast_op;
   OPCODE  undef_op;
+  OPCODE  retry_userc_op;
 
   UInt  n_of_atoms;
   UInt  atom_hash_table_size;
@@ -228,7 +229,6 @@
   UInt  dirty_cps;
   UInt  freed_cps;
 #endif
-
   UInt  expand_clauses_sz;
 
   struct udi_info  *udi_control_blocks;
diff --git a/H/ihstruct.h b/H/ihstruct.h
index 04d993f4e..b2d47aa5b 100644
--- a/H/ihstruct.h
+++ b/H/ihstruct.h
@@ -71,6 +71,7 @@
   LOCKPRED_OPCODE = Yap_opcode(_lock_pred);
   ORLAST_OPCODE = Yap_opcode(_or_last);
   UNDEF_OPCODE = Yap_opcode(_undef_p);
+  RETRY_USERC_OPCODE = Yap_opcode(_retry_userc);
 
 
 
diff --git a/H/ilocals.h b/H/ilocals.h
index bbd21acc0..e02715073 100644
--- a/H/ilocals.h
+++ b/H/ilocals.h
@@ -232,5 +232,7 @@ static void InitWorker(int wid) {
   REMOTE_exo_arg(wid) = 0;
 
 
+
+  REMOTE_CurSlot(wid) = 0;
   REMOTE_SourceModule(wid) = 0;
 }
diff --git a/H/pl-yap.h b/H/pl-yap.h
index e334cfcf6..14875b3bc 100644
--- a/H/pl-yap.h
+++ b/H/pl-yap.h
@@ -124,7 +124,7 @@ void PL_license(const char *license, const char *module);
 
 #define arityFunctor(f) YAP_PLArityOfSWIFunctor(f)
 
-#define stringAtom(w)	YAP_AtomName(YAP_AtomFromSWIAtom(w))
+#define stringAtom(w)	(YAP_AtomFromSWIAtom(w)->StrOfAE)
 #define isInteger(A) (!IsVarTerm(A) && ( IsIntegerTerm((A)) || YAP_IsBigNumTerm((A)) ))
 #define isString(A) (!IsVarTerm(A) && Yap_IsStringTerm(A) )
 #define isAtom(A) (!IsVarTerm(A) && IsAtomTerm((A)) )
diff --git a/H/rhstruct.h b/H/rhstruct.h
index 43fe14b91..f6500dac7 100644
--- a/H/rhstruct.h
+++ b/H/rhstruct.h
@@ -71,6 +71,7 @@
   LOCKPRED_OPCODE = Yap_opcode(_lock_pred);
   ORLAST_OPCODE = Yap_opcode(_or_last);
   UNDEF_OPCODE = Yap_opcode(_undef_p);
+  RETRY_USERC_OPCODE = Yap_opcode(_retry_userc);
 
 
 
diff --git a/H/rlocals.h b/H/rlocals.h
index df9184d10..742dfd5de 100644
--- a/H/rlocals.h
+++ b/H/rlocals.h
@@ -230,6 +230,8 @@ static void RestoreWorker(int wid USES_REGS) {
 
 
 
+
+
 
 
 
diff --git a/misc/HEAPFIELDS b/misc/HEAPFIELDS
index 48f8e9e24..77d8e417c 100644
--- a/misc/HEAPFIELDS
+++ b/misc/HEAPFIELDS
@@ -70,6 +70,7 @@ OPCODE		index_op		INDEX_OPCODE		MkOp _index_pred
 OPCODE		lockpred_op		LOCKPRED_OPCODE		MkOp _lock_pred
 OPCODE		orlast_op		ORLAST_OPCODE		MkOp _or_last
 OPCODE		undef_op		UNDEF_OPCODE		MkOp _undef_p
+OPCODE		retry_userc_op		RETRY_USERC_OPCODE	MkOp _retry_userc
 
 /* atom tables */
 UInt		n_of_atoms		NOfAtoms		void void
diff --git a/misc/LOCALS b/misc/LOCALS
index 9172055b8..668f7a5d6 100644
--- a/misc/LOCALS
+++ b/misc/LOCALS
@@ -265,6 +265,10 @@ UInt				exo_arg					=0
 // atom completion
 struct scan_atoms*		search_atoms				void
 
+// Slots
+Int				CurSlot					=0
+
+
 Term				SourceModule				=0
 
 END_WORKER_LOCAL