diff --git a/GNUmakefile b/GNUmakefile
index c6b8d9a1..fbe63fe0 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -24,7 +24,6 @@ all: mes
 
 mes.o: mes.c
 mes.o: mes.c mes.h mes.i mes.environment.i mes.symbols.i
-mes.o: cache.c cache.h cache.i cache.environment.i
 mes.o: define.c define.h define.i define.environment.i
 mes.o: display.c display.h display.i display.environment.i
 mes.o: lib.c lib.h lib.i lib.environment.i
diff --git a/cache.c b/cache.c
deleted file mode 100644
index 58e03f18..00000000
--- a/cache.c
+++ /dev/null
@@ -1,103 +0,0 @@
-/* -*-comment-start: "//";comment-end:""-*-
- * Mes --- Maxwell Equations of Software
- * Copyright © 2016 Jan Nieuwenhuizen <janneke@gnu.org>
- *
- * This file is part of Mes.
- *
- * Mes is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 3 of the License, or (at
- * your option) any later version.
- *
- * Mes is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with Mes.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-#define CACHE_SIZE 30
-#define ENV_HEAD 15
-
-#if! ENV_CACHE
-SCM cache_invalidate (SCM x){}
-SCM cache_invalidate_range (SCM p,SCM a){}
-SCM cache_save (SCM p){}
-SCM cache_lookup (SCM x){}
-#else // ENV_CACHE
-
-SCM env_cache_cars[CACHE_SIZE];
-SCM env_cache_cdrs[CACHE_SIZE];
-int cache_threshold = 0;
-SCM
-cache_save (SCM p)
-{
-  int n = g_cells[car (p)].hits;
-  if (n < cache_threshold) return cell_unspecified;
-  int j = -1;
-  for (int i=0; i < CACHE_SIZE; i++) {
-    if (!env_cache_cars[i]) {
-      j = i;
-      break;
-    }
-    if (env_cache_cars[i] == car (p)) return cell_unspecified;
-    if (n > g_cells[env_cache_cars[i]].hits) {
-      n = g_cells[env_cache_cars[i]].hits;
-      j = i;
-    }
-  }
-  if (j >= 0) {
-    cache_threshold = g_cells[car (p)].hits;
-    env_cache_cars[j] = car (p);
-    env_cache_cdrs[j] = cdr (p);
-  }
-  return cell_unspecified;
-}
-
-SCM
-cache_lookup (SCM x)
-{
-  for (int i=0; i < CACHE_SIZE; i++) {
-    if (!env_cache_cars[i]) break;
-    if (env_cache_cars[i] == x) return env_cache_cdrs[i];
-  }
-  return cell_undefined;
-}
-
-SCM
-cache_invalidate (SCM x)
-{
-  for (int i=0; i < CACHE_SIZE; i++) {
-    if (env_cache_cars[i] == x) {
-      env_cache_cars[i] = 0;
-      break;
-    }
-  }
-  return cell_unspecified;
-}
-
-SCM
-cache_invalidate_range (SCM p, SCM a)
-{
-  do {
-    cache_invalidate (caar (p));
-    p = cdr (p);
-  } while (p != a);
-  return cell_unspecified;
-}
-
-SCM
-assq_ref_cache (SCM x, SCM a) ///((internal))
-{
-  g_cells[x].hits++;
-  SCM c = cache_lookup (x);
-  if (c != cell_undefined) return c;
-  int i = 0;
-  while (a != cell_nil && x != CAAR (a)) {i++;a = cdr (a);}
-  if (a == cell_nil) return cell_undefined;
-  if (i>ENV_HEAD) cache_save (car (a));
-  return cdar (a);
-}
-#endif // ENV_CACHE
diff --git a/define.c b/define.c
index dd661218..31521197 100644
--- a/define.c
+++ b/define.c
@@ -35,7 +35,6 @@ vm_define_env ()
   else {
     r2 = car (r2);
     SCM p = pairlis (cadr (r1), cadr (r1), r0);
-    cache_invalidate_range (p, r0);
     x = eval_env (make_lambda (cdadr (r1), cddr (r1)), p);
   }
   if (eq_p (car (r1), cell_symbol_define_macro) == cell_t)
diff --git a/mes.c b/mes.c
index 91705885..e1956300 100644
--- a/mes.c
+++ b/mes.c
@@ -31,7 +31,8 @@
 #define DEBUG 0
 #define QUASIQUOTE 1
 #define QUASISYNTAX 0
-#define ENV_CACHE 1
+#define ENV_CACHE 0
+#define FIXED_PRIMITIVES 1
 
 int ARENA_SIZE = 100000;
 int MAX_ARENA_SIZE = 20000000;
@@ -78,7 +79,6 @@ function functions[200];
 int g_function = 0;
 
 #include "mes.symbols.h"
-#include "cache.h"
 #include "define.h"
 #include "display.h"
 #include "lib.h"
@@ -144,6 +144,12 @@ scm scm_symbol_primitive_load = {SYMBOL, "primitive-load"};
 
 scm scm_symbol_the_unquoters = {SYMBOL, "*the-unquoters*"};
 
+scm scm_symbol_car = {SYMBOL, "car"};
+scm scm_symbol_cdr = {SYMBOL, "cdr"};
+scm scm_symbol_null_p = {SYMBOL, "null?"};
+scm scm_symbol_eq_p = {SYMBOL, "eq?"};
+scm scm_symbol_cons = {SYMBOL, "cons"};
+
 scm char_eof = {CHAR, .name="*eof*", .value=-1};
 scm char_nul = {CHAR, .name="nul", .value=0};
 scm char_backspace = {CHAR, .name="backspace", .value=8};
@@ -177,6 +183,7 @@ scm *g_news = 0;
 #define CDAR(x) CDR (CAR (x))
 #define CAAR(x) CAR (CAR (x))
 #define CADAR(x) CAR (CDR (CAR (x)))
+#define CADDR(x) CAR (CDR (CDR (x)))
 #define CDADAR(x) CAR (CDR (CAR (CDR (x))))
 #define CADR(x) CAR (CDR (x))
 
@@ -255,7 +262,6 @@ SCM
 set_cdr_x (SCM x, SCM e)
 {
   assert (TYPE (x) == PAIR);
-  cache_invalidate (cdr (x));
   CDR (x) = e;
   return cell_unspecified;
 }
@@ -263,7 +269,6 @@ set_cdr_x (SCM x, SCM e)
 SCM
 set_env_x (SCM x, SCM e, SCM a)
 {
-  cache_invalidate (x);
   SCM p = assert_defined (x, assq (x, a));
   return set_cdr_x (p, e);
 }
@@ -309,7 +314,6 @@ assq (SCM x, SCM a)
   return a != cell_nil ? car (a) : cell_f;
 }
 
-#if! ENV_CACHE
 SCM
 assq_ref_cache (SCM x, SCM a)
 {
@@ -317,7 +321,6 @@ assq_ref_cache (SCM x, SCM a)
   if (x == cell_f) return cell_undefined;
   return cdr (x);
 }
-#endif // !ENV_CACHE
 
 SCM
 assert_defined (SCM x, SCM e)
@@ -356,10 +359,7 @@ call_lambda (SCM e, SCM x, SCM aa, SCM a) ///((internal))
   r0 = cl;
   r2 = a;
   r3 = aa;
-  cache_invalidate_range (r0, CDR (r3));
-  SCM r = vm_call_lambda ();
-  cache_invalidate_range (r0, CDR (r3));
-  return r;
+  return vm_call_lambda ();
 }
 
 SCM
@@ -417,6 +417,18 @@ vm_eval_env ()
     {
     case PAIR:
       {
+#if FIXED_PRIMITIVES
+        if (car (r1) == cell_symbol_car)
+          return car (eval_env (CADR (r1), r0));
+        if (car (r1) == cell_symbol_cdr)
+          return cdr (eval_env (CADR (r1), r0));
+        if (car (r1) == cell_symbol_cons) {
+          SCM m = evlis_env (CDR (r1), r0);
+          return cons (CAR (m), CADR (m));
+        }
+        if (car (r1) == cell_symbol_null_p)
+          return null_p (eval_env (CADR (r1), r0));
+#endif // FIXED_PRIMITIVES
         if (car (r1) == cell_symbol_quote)
           return cadr (r1);
 #if QUASISYNTAX
@@ -589,10 +601,7 @@ vm_call (function0_t f, SCM p1, SCM p2, SCM a)
   r2 = p2;
   r0 = a;
   if (g_free.value + GC_SAFETY > ARENA_SIZE)
-    {
-      cache_invalidate_range (r0, cell_nil);
-      gc_stack (stack);
-    }
+    gc_stack (stack);
 
   SCM r = f ();
   frame = gc_frame (stack);
@@ -1086,7 +1095,6 @@ mes_builtins (SCM a)
 {
 #include "mes.i"
 
-#include "cache.i"
 #include "define.i"
 #include "display.i"
 #include "lib.i"
@@ -1097,7 +1105,6 @@ mes_builtins (SCM a)
 #include "string.i"
 #include "type.i"
 
-#include "cache.environment.i"
 #include "define.environment.i"
 #include "display.environment.i"
 #include "lib.environment.i"
@@ -1228,7 +1235,6 @@ bload_env (SCM a)
 }
 
 #include "type.c"
-#include "cache.c"
 #include "define.c"
 #include "display.c"
 #include "lib.c"