diff --git a/scheme/bcomp/comp-prim.scm b/scheme/bcomp/comp-prim.scm
index 05d24aa..6fb60a6 100644
--- a/scheme/bcomp/comp-prim.scm
+++ b/scheme/bcomp/comp-prim.scm
@@ -223,20 +223,6 @@
             (apply define-data-struct-primitives stuff))
           stob-data)
 
-; For flat environments
-
-(let ((:value (sexp->type ':value #t))
-      (:vector (sexp->type ':vector #t)))
-  (define-simple-primitive 'make-cell
-    (proc (:value) :vector)
-    (instruction (enum op make-stored-object) 1 (enum stob vector)))
-  (define-simple-primitive 'cell-ref
-    (proc (:vector) :value)
-    (instruction (enum op stored-object-ref) (enum stob vector) 0))
-  (define-simple-primitive 'cell-set!
-    (proc (:vector :value) unspecific-type)
-    (instruction (enum op stored-object-set!) (enum stob vector) 0)))
-
 ; Define primitives for vector-like stored objects.
 
 (define (define-vector-primitives name element-type make length ref set!)
diff --git a/scheme/interfaces.scm b/scheme/interfaces.scm
index da51c7e..e909627 100644
--- a/scheme/interfaces.scm
+++ b/scheme/interfaces.scm
@@ -112,6 +112,12 @@
 	  ((bitwise-and bitwise-ior bitwise-xor)
 	   (proc (&rest :exact-integer) :exact-integer))))
 
+(define-interface cells-interface
+  (export cell?
+	  make-cell
+	  cell-ref
+	  cell-set!))
+
 (define-interface locations-interface
   (export location?
 	  location-defined?
diff --git a/scheme/low-packages.scm b/scheme/low-packages.scm
index fea64b9..9a3d238 100644
--- a/scheme/low-packages.scm
+++ b/scheme/low-packages.scm
@@ -18,6 +18,7 @@
 		    (vm-exposure vm-exposure-interface)
 		    (ascii ascii-interface)
 		    (locations locations-interface)
+		    (cells cells-interface)
 		    (low-channels low-channels-interface)
 		    (ports ports-interface)
 		    (shared-bindings shared-bindings-interface)
diff --git a/scheme/packages.scm b/scheme/packages.scm
index 8464f08..402295e 100644
--- a/scheme/packages.scm
+++ b/scheme/packages.scm
@@ -234,6 +234,7 @@
   (export ((ascii
 	    bitwise
 	    byte-vectors
+	    cells
 	    code-vectors
 	    features
 	    ;; records  - lose
diff --git a/scheme/vm/arch.scm b/scheme/vm/arch.scm
index a2fde31..fe9fbe8 100644
--- a/scheme/vm/arch.scm
+++ b/scheme/vm/arch.scm
@@ -398,6 +398,7 @@
    vector
    closure
    location
+   cell
    channel
    port
    ratnum
@@ -432,6 +433,8 @@
     (location location? make-location
       (location-id set-location-id!)
       (contents set-contents!))
+    (cell cell? make-cell
+      (cell-ref cell-set!))
     (closure closure? make-closure
       (closure-template) (closure-env))
     (weak-pointer weak-pointer? make-weak-pointer
diff --git a/scheme/vm/interfaces.scm b/scheme/vm/interfaces.scm
index 7f3af39..3887c01 100644
--- a/scheme/vm/interfaces.scm
+++ b/scheme/vm/interfaces.scm
@@ -248,6 +248,7 @@
 	  vm-symbol-next vm-set-symbol-next!
 	  closure? closure-size make-closure closure-template closure-env
 	  location? location-size make-location contents set-contents! location-id
+  	  cell? cell-size make-cell cell-ref cell-set!
 	  weak-pointer? weak-pointer-size make-weak-pointer weak-pointer-ref
 
 	  shared-binding? shared-binding-size make-shared-binding
diff --git a/scheme/vm/struct.scm b/scheme/vm/struct.scm
index 75ebd13..33992a9 100644
--- a/scheme/vm/struct.scm
+++ b/scheme/vm/struct.scm
@@ -22,6 +22,7 @@
   (symbol-next set-symbol-next!))       		; hidden from RTS
 (define-shared-primitive-data-type closure #f #t)
 (define-shared-primitive-data-type location)
+(define-shared-primitive-data-type cell)
 (define-shared-primitive-data-type weak-pointer)
 (define-shared-primitive-data-type shared-binding #f #f
   #f