diff --git a/i/n/a.h b/i/n/a.h
index f13590230..4a6d60f50 100644
--- a/i/n/a.h
+++ b/i/n/a.h
@@ -125,8 +125,8 @@
         } all;
 
         struct {                              //  jet dashboard
-          u3p(u3h_root) har_p;                //  jet index (old style)
-          u3_noun         das;                //  dashboard (new style)
+          u3p(u3h_root) har_p;                //  warm state
+          u3_noun       das;                  //  cold state
         } jed;
 
         struct {                              //  namespace
diff --git a/i/n/e.h b/i/n/e.h
index 4c3fd1016..ab69b67fe 100644
--- a/i/n/e.h
+++ b/i/n/e.h
@@ -40,7 +40,7 @@
     /* u3e_pool: entire memory system.
     */
       typedef struct _u3e_pool {
-        c3_c*        cpu_c;                     //  path to 
+        c3_c*        dir_c;                     //  path to 
         c3_d         evt_d;                     //  last patch written at event
         c3_w         dit_w[u3a_pages >> 5];   //  touched since last save
         u3e_image  nor_u;                     //  north segment
@@ -68,10 +68,15 @@
       void
       u3e_save(void);
 
-    /* u3e_boot(): start the memory system.
+    /* u3e_live(): start the persistence system.
+    */
+      void
+      u3e_live(c3_o nuu_o, c3_c* dir_c);
+
+    /* u3e_boot(): start the u3 system.
     */
       void 
-      u3e_boot(c3_o nuu_o, c3_o bug_o, c3_c* cpu_c);
+      u3e_boot(c3_o nuu_o, c3_o bug_o, c3_c* dir_c);
 
     /* u3e_init(): start the environment, with/without checkpointing.
     */
diff --git a/i/n/j.h b/i/n/j.h
index da4249775..dbd6dd1ee 100644
--- a/i/n/j.h
+++ b/i/n/j.h
@@ -9,12 +9,18 @@
   ++  bash  ,@uvH                                         ::  ctx identity hash
   ++  bosh  ,@uvH                                         ::  local battery hash
   ++  batt  ,*                                            ::  battery
-  ++  calx                                                ::  cached by battery
+  ++  calf                                                ::  
     $:  jax=,@ud                                          ::  jet index
         pax=,@ud                                          ::  parent axis or 0
         hap=(map ,@ud ,@ud)                               ::  axis/jet
-        huc=(map term nock)                               ::  name/tool
     ==                                                    ::
+  ++  calx  (trel calf ,* (map term nock))                ::  cached by battery
+  ++  chum  $?  lef=term                                  ::  jet name
+                [std=term kel=@]                          ::  kelvin version
+                [ven=term pro=term kel=@]                 ::  vendor and product
+                [ven=term pro=term ver=@ kel=@]           ::  all of the above
+            ==                                            ::
+  ++  clue  ,[p=chum q=nock r=(list (pair term nock))]    ::  battery definition
   ++  clog  (pair cope (map batt (map term nock)))        ::  identity record
   ++  cope  (trel bane axis (each bash noun))             ::  core pattern
   ++  dash                                                ::  jet system
@@ -60,39 +66,35 @@
 
   /** Data structures.
   ***
-  *** All of these are transient structures allocated with malloc.
+  *** All of these are process structures on the heap or data segment.
   **/
     /* u3j_harm: jet arm.
     */
       typedef struct _u3j_harm {
-        c3_c*               fcs_c;             //  `.axe` or name
-        u3_noun           (*fun_f)(u3_noun);   //  compute or 0 / semitransfer
-        // c3_o           (*val_f)(u3_noun);   //  validate or 0 / retain
-        c3_o                ice;               //  perfect (don't test)
-        c3_o                tot;               //  total (never punts)
-        c3_o                liv;               //  live (enabled)
-        c3_l                axe_l;             //  computed/discovered axis
-        struct _u3j_core* cop_u;             //  containing core
+        c3_c*               fcs_c;            //  `.axe` or name
+        u3_noun           (*fun_f)(u3_noun);  //  compute or 0 / semitransfer
+        c3_o                ice;              //  perfect (don't test)
+        c3_o                tot;              //  total (never punts)
+        c3_o                liv;              //  live (enabled)
       } u3j_harm;
 
     /* u3j_core: driver definition.
     */
       typedef struct _u3j_core {
-        c3_c*               cos_c;      //  control string
-        struct _u3j_harm* arm_u;      //  blank-terminated static list
-        struct _u3j_core* dev_u;      //  blank-terminated static list
-        struct _u3j_core* par_u;      //  dynamic parent pointer 
-        c3_l                axe_l;      //  axis to parent
-        c3_l                jax_l;      //  index in global dashboard
+        c3_c*             cos_c;              //  control string
+        struct _u3j_harm* arm_u;              //  blank-terminated static list
+        struct _u3j_core* dev_u;              //  blank-terminated static list
+        struct _u3j_core* par_u;              //  initialized parent pointer 
+        c3_l              jax_l;              //  initialized jet index
       } u3j_core;
 
     /* u3e_dash, u3_Dash, u3D: jet dashboard singleton
     */
       typedef struct _u3e_dash {
-        u3j_core* dev_u;              //  null-terminated static list
-        c3_l        len_l;              //  dynamic array length
-        c3_l        all_l;              //  allocated length
-        u3j_core* ray_u;              //  dynamic array by axis
+        u3j_core* dev_u;                      //  null-terminated static list
+        c3_l      len_l;                      //  dynamic array length
+        c3_l      all_l;                      //  allocated length
+        u3j_core* ray_u;                      //  dynamic array by axis
       } u3j_dash;
 
   /** Globals.
@@ -110,11 +112,6 @@
         void
         u3j_boot(void);
 
-      /* u3j_clear(): clear jet table to re-register.
-      */
-        void
-        u3j_clear(void);
-
       /* u3j_hook():
       **
       **   Execute hook from core. 
@@ -145,19 +142,17 @@
       */
         u3_weak
         u3j_kick(u3_noun cor,
-                   u3_noun axe);
+                 u3_noun axe);
 
       /* u3j_kink(): kick either by jet or by nock.
       */
         u3_noun
-        u3j_kink(u3_noun cor,
-                   u3_noun axe);
+        u3j_kink(u3_noun cor, u3_noun axe);
  
       /* u3j_mine(): register core for jets.
       */
         void
-        u3j_mine(u3_noun clu,
-                   u3_noun cor);
+        u3j_mine(u3_noun clu, u3_noun cor);
 
       /* u3j_ream(): refresh after restoring from checkpoint.
       */
diff --git a/i/n/m.h b/i/n/m.h
index 292190058..10326e717 100644
--- a/i/n/m.h
+++ b/i/n/m.h
@@ -4,24 +4,10 @@
 */
     /** System management.
     **/
-      /* u3m_boot(): set up top-level road.
+      /* u3m_boot(): start the u3 system.
       */
         void
-        u3m_boot(c3_o nuu_o, c3_o bug_o);
-
-      /* u3m_trap(): setjmp within road.
-      */
-#if 0
-        c3_o
-        u3m_trap(void);
-#else
-#       define u3m_trap() (u3_noun)(setjmp(u3R->esc.buf))
-#endif
-
-      /* u3m_signal(): treat a nock-level exception as a signal interrupt.
-      */
-        void
-        u3m_signal(u3_noun sig_l);
+        u3m_boot(c3_o nuu_o, c3_o bug_o, c3_c* dir_c);
 
       /* u3m_bail(): bail out.  Does not return.
       **
@@ -34,45 +20,22 @@
       **    %foul               ::  assert failure
       **    %need               ::  network block
       **    %meme               ::  out of memory
+      **    %time               ::  timed out
+      **    %oops               ::  assertion failure
       */ 
         c3_i
         u3m_bail(c3_m how_m);
 
-      /* u3m_dump(): dump the current road to stderr.
-      */
-        void
-        u3m_dump(void);
-
       /* u3m_file(): load file, as atom, or bail.
       */
         u3_noun
         u3m_file(c3_c* pas_c);
 
-      /* u3m_clear(): clear all allocated data in road.
-      */
-        void
-        u3m_clear(void);
-
-      /* u3m_mark(): mark all nouns in the road.
-      */
-        void
-        u3m_mark(void);
-
       /* u3m_error(): bail out with %exit, ct_pushing error.
       */
         c3_i
         u3m_error(c3_c* str_c);
 
-      /* u3m_check(): checkpoint memory to file.  Asserts u3R == u3H.
-      */
-        void
-        u3m_check(void);
-
-      /* u3m_fall(): return to parent road.
-      */
-        void
-        u3m_fall(void);
-
       /* u3m_hate(): new, integrated leap mechanism (enter).
       */
         void
@@ -83,32 +46,6 @@
         u3_noun
         u3m_love(u3_noun pro);
 
-      /* u3m_leap(): in u3R, create a new road within the existing one.
-      */
-        void
-        u3m_leap(c3_w pad_w);
-
-      /* u3m_golf(): record cap length for u3_flog().
-      */
-        c3_w
-        u3m_golf(void);
-
-      /* u3m_flog(): pop the cap.
-      **
-      **    A common sequence for inner allocation is:
-      **
-      **    c3_w gof_w = u3m_golf();
-      **    u3m_leap();
-      **    //  allocate some inner stuff...
-      **    u3m_fall();
-      **    //  inner stuff is still valid, but on cap
-      **    u3m_flog(gof_w);
-      **
-      ** u3m_flog(0) simply clears the cap.
-      */
-        void
-        u3m_flog(c3_w gof_w);
-
       /* u3m_soft(): system soft wrapper.  unifies unix and nock errors.
       **
       **  Produces [%$ result] or [%error (list tank)].
@@ -116,19 +53,16 @@
         u3_noun
         u3m_soft(c3_w sec_w, u3_funk fun_f, u3_noun arg);
 
-      /* u3m_soft_top(): top-level safety wrapper.
-      */
-        u3_noun 
-        u3m_soft_top(c3_w    sec_w,                     //  timer seconds
-                     c3_w    pad_w,                     //  base memory pad
-                     u3_funk fun_f,
-                     u3_noun arg);
-
       /* u3m_soft_slam: top-level call.
       */
         u3_noun 
         u3m_soft_slam(u3_noun gat, u3_noun sam);
 
+      /* u3m_soft_nock: top-level nock.
+      */
+        u3_noun 
+        u3m_soft_nock(u3_noun bus, u3_noun fol);
+
       /* u3m_soft_sure(): top-level call assumed correct.
       */
         u3_noun 
@@ -138,9 +72,9 @@
       */
         u3_noun 
         u3m_soft_run(u3_noun fly,
-                       u3_funq fun_f,
-                       u3_noun aga,
-                       u3_noun agb);
+                     u3_funq fun_f,
+                     u3_noun aga,
+                     u3_noun agb);
 
       /* u3m_soft_esc(): namespace lookup to (unit ,*).
       */
diff --git a/i/v/vere.h b/i/v/vere.h
index be4cb4fc4..8b2c6ea67 100644
--- a/i/v/vere.h
+++ b/i/v/vere.h
@@ -537,8 +537,7 @@
     */
       typedef struct _u3_host {
         c3_w       kno_w;                   //  current executing stage
-        c3_c*      cpu_c;                   //  computer path
-
+        c3_c*      dir_c;                   //  pier path
         c3_d       now_d;                   //  event tick
         uv_loop_t* lup_u;                   //  libuv event loop
         u3_http*   htp_u;                   //  http servers
diff --git a/j/d/by_get.c b/j/d/by_get.c
index cd0adf06d..ce805d6af 100644
--- a/j/d/by_get.c
+++ b/j/d/by_get.c
@@ -36,8 +36,7 @@
     }
   }
   u3_noun
-  u3wdb_get(
-                      u3_noun cor)
+  u3wdb_get(u3_noun cor)
   {
     u3_noun a, b;
 
diff --git a/n/e.c b/n/e.c
index 557434388..9120bdc35 100644
--- a/n/e.c
+++ b/n/e.c
@@ -5,9 +5,6 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <sys/stat.h>
-#include <sigsegv.h>
-#include <pmmintrin.h>
-#include <xmmintrin.h>
 
 #include "all.h"
 
@@ -168,16 +165,16 @@ _ce_image_open(u3e_image* img_u, c3_o nuu_o)
   c3_i mod_i = _(nuu_o) ? (O_RDWR | O_CREAT) : O_RDWR;
   c3_c ful_c[8193];
 
-  snprintf(ful_c, 8192, "%s", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s", u3P.dir_c);
   mkdir(ful_c, 0700);
 
-  snprintf(ful_c, 8192, "%s/.urb", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s/.urb", u3P.dir_c);
   mkdir(ful_c, 0700);
 
-  snprintf(ful_c, 8192, "%s/.urb/chk", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s/.urb/chk", u3P.dir_c);
   mkdir(ful_c, 0700);
 
-  snprintf(ful_c, 8192, "%s/.urb/chk/%s.bin", u3P.cpu_c, img_u->nam_c);
+  snprintf(ful_c, 8192, "%s/.urb/chk/%s.bin", u3P.dir_c, img_u->nam_c);
   if ( -1 == (img_u->fid_i = open(ful_c, mod_i, 0666)) ) {
     perror(ful_c);
     return c3n;
@@ -266,18 +263,18 @@ _ce_patch_create(u3_ce_patch* pat_u)
 {
   c3_c ful_c[8193];
 
-  snprintf(ful_c, 8192, "%s", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s", u3P.dir_c);
   mkdir(ful_c, 0700);
 
-  snprintf(ful_c, 8192, "%s/.urb", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s/.urb", u3P.dir_c);
   mkdir(ful_c, 0700);
 
-  snprintf(ful_c, 8192, "%s/.urb/chk/control.bin", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s/.urb/chk/control.bin", u3P.dir_c);
   if ( -1 == (pat_u->ctl_i = open(ful_c, O_RDWR | O_CREAT | O_EXCL, 0666)) ) {
     c3_assert(0);
   }
 
-  snprintf(ful_c, 8192, "%s/.urb/chk/memory.bin", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s/.urb/chk/memory.bin", u3P.dir_c);
   if ( -1 == (pat_u->mem_i = open(ful_c, O_RDWR | O_CREAT | O_EXCL, 0666)) ) {
     c3_assert(0);
   }
@@ -290,10 +287,10 @@ _ce_patch_delete(void)
 {
   c3_c ful_c[8193];
 
-  snprintf(ful_c, 8192, "%s/.urb/chk/control.bin", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s/.urb/chk/control.bin", u3P.dir_c);
   unlink(ful_c);
 
-  snprintf(ful_c, 8192, "%s/.urb/chk/memory.bin", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s/.urb/chk/memory.bin", u3P.dir_c);
   unlink(ful_c);
 }
 
@@ -358,18 +355,18 @@ _ce_patch_open(void)
   c3_c ful_c[8193];
   c3_i ctl_i, mem_i;
 
-  snprintf(ful_c, 8192, "%s", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s", u3P.dir_c);
   mkdir(ful_c, 0700);
 
-  snprintf(ful_c, 8192, "%s/.urb", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s/.urb", u3P.dir_c);
   mkdir(ful_c, 0700);
 
-  snprintf(ful_c, 8192, "%s/.urb/chk/control.bin", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s/.urb/chk/control.bin", u3P.dir_c);
   if ( -1 == (ctl_i = open(ful_c, O_RDWR)) ) {
     return 0;
   }
 
-  snprintf(ful_c, 8192, "%s/.urb/chk/memory.bin", u3P.cpu_c);
+  snprintf(ful_c, 8192, "%s/.urb/chk/memory.bin", u3P.dir_c);
   if ( -1 == (mem_i = open(ful_c, O_RDWR)) ) {
     close(ctl_i);
 
@@ -808,149 +805,12 @@ u3e_save(void)
   _ce_patch_free(pat_u);
 }
 
-/* _ce_limits(): set up global modes and limits.
-*/
-static void
-_ce_limits(void)
-{
-  struct rlimit rlm;
-  c3_i          ret_i;
-
-  /* Set compatible floating-point modes.
-  */
-  {
-    _MM_SET_FLUSH_ZERO_MODE(_MM_FLUSH_ZERO_ON);
-    _MM_SET_DENORMALS_ZERO_MODE(_MM_DENORMALS_ZERO_ON);
-  }
-
-  /* Moar stack.
-  */
-  {
-    ret_i = getrlimit(RLIMIT_STACK, &rlm);
-    c3_assert(0 == ret_i);
-    rlm.rlim_cur = (rlm.rlim_max > (65536 << 10)) 
-                          ? (65536 << 10)
-                          : rlm.rlim_max;
-    if ( 0 != setrlimit(RLIMIT_STACK, &rlm) ) {
-      perror("stack");
-      exit(1);
-    }
-  }
-
-  /* Moar filez.
-  */
-  {
-    ret_i = getrlimit(RLIMIT_NOFILE, &rlm);
-    c3_assert(0 == ret_i);
-    rlm.rlim_cur = 4096;
-    if ( 0 != setrlimit(RLIMIT_NOFILE, &rlm) ) {
-      perror("file limit");
-      //  no exit, not a critical limit
-    }
-  }
-
-  /* Moar core.
-  */
-  {
-    getrlimit(RLIMIT_CORE, &rlm);
-    rlm.rlim_cur = RLIM_INFINITY;
-    if ( 0 != setrlimit(RLIMIT_CORE, &rlm) ) {
-      perror("core limit");
-      //  no exit, not a critical limit
-    }
-  }
-}
-
-/* _ce_signals(): set up interrupts, etc.
-*/
-static void
-_ce_signals(void)
-{
-  if ( 0 != sigsegv_install_handler(u3e_fault) ) {
-    fprintf(stderr, "sigsegv install failed\n");
-    exit(1);
-  }
-  // signal(SIGINT, _loom_stop);
-}
-
-/* u3e_init(): start the environment, with/without checkpointing.
+/* u3e_live(): start the persistence system.
 */
 void
-u3e_init(c3_o chk_o)
+u3e_live(c3_o nuu_o, c3_c* dir_c)
 {
-  _ce_limits();
-  _ce_signals();
-
-  /* Make sure GMP uses our malloc.
-  */
-  mp_set_memory_functions(u3a_malloc, u3a_realloc2, u3a_free2);
-
-  /* Map at fixed address.
-  */
-  {
-    c3_w  len_w = u3a_bytes;
-    void* map_v;
-
-    map_v = mmap((void *)u3_Loom,
-                 len_w,
-                 _(chk_o) ? PROT_READ : (PROT_READ | PROT_WRITE),
-                 (MAP_ANON | MAP_FIXED | MAP_PRIVATE),
-                 -1, 0);
-
-    if ( -1 == (c3_ps)map_v ) {
-      map_v = mmap((void *)0,
-                   len_w,
-                   PROT_READ,
-                   MAP_ANON | MAP_PRIVATE,
-                   -1, 0);
-
-      if ( -1 == (c3_ps)map_v ) {
-        fprintf(stderr, "boot: map failed twice\r\n");
-      } else {
-        fprintf(stderr, "boot: map failed - try U3_OS_LoomBase %p\r\n", map_v);
-      }
-      exit(1);
-    }
-    printf("loom: mapped %dMB\r\n", len_w >> 20);
-  }
-}
-
-/* u3e_grab(): garbage-collect the world, plus extra roots, then 
-*/
-void
-u3e_grab(c3_c* cap_c, u3_noun som, ...)   // terminate with u3_none
-{
-  // u3h_free(u3R->cax.har_p);
-  // u3R->cax.har_p = u3h_new();
-
-  u3v_mark();
-  u3m_mark();
-  {
-    va_list vap;
-    u3_noun tur;
-
-    va_start(vap, som);
-
-    if ( som != u3_none ) {
-      u3a_mark_noun(som);
-
-      while ( u3_none != (tur = va_arg(vap, u3_noun)) ) {
-        u3a_mark_noun(tur);
-      }
-    }
-    va_end(vap);
-  }
-  u3a_sweep(cap_c);
-}
-
-/* u3e_boot(): start the u3 system.
-*/
-void
-u3e_boot(c3_o nuu_o, c3_o bug_o, c3_c* cpu_c)
-{
-  u3e_init(nuu_o);
-
-  u3P.cpu_c = cpu_c;
+  u3P.dir_c = dir_c;
   u3P.nor_u.nam_c = "north";
   u3P.sou_u.nam_c = "south";
 
@@ -1019,32 +879,4 @@ u3e_boot(c3_o nuu_o, c3_o bug_o, c3_c* cpu_c)
       nuu_o = c3y;
     }
   }
-
-  /* Construct or activate the allocator.
-  */
-  u3m_boot(nuu_o, bug_o);
-
-  /* Initialize the jet system.
-  */
-  u3j_boot();
-
-  /* Install the kernel.
-  */
-  if ( _(nuu_o) ) {
-    c3_c pas_c[2049];
-    struct stat buf_u;
-
-    snprintf(pas_c, 2048, "%s/.urb/urbit.pill", cpu_c);
-    if ( -1 == stat(pas_c, &buf_u) ) {
-      snprintf(pas_c, 2048, "%s/urbit.pill", U3_LIB);
-    }
-    printf("boot: loading %s\r\n", pas_c);
-    u3v_make(pas_c);
-
-    u3v_jack();
-  }
-  else {
-    u3v_hose();
-    u3j_ream();
-  }
 }
diff --git a/n/j.c b/n/j.c
index 83c305e2c..3043aed97 100644
--- a/n/j.c
+++ b/n/j.c
@@ -355,12 +355,12 @@ _cj_warm_hump(c3_l jax_l, u3_noun huc)
   return hap;
 }
 
-/* _cj_boil_mean(): in parent, declare a core.  RETAINS.
+/* _cj_hot_mean(): in parent, declare a core.  RETAINS.
 **
 ** XX bat is used only for printing, remove.
 */
 static c3_l
-_cj_boil_mean(c3_l par_l, u3_noun mop, u3_noun bat)
+_cj_hot_mean(c3_l par_l, u3_noun mop, u3_noun bat)
 {
   u3j_core* par_u;
   u3j_core* dev_u;
@@ -395,10 +395,10 @@ _cj_boil_mean(c3_l par_l, u3_noun mop, u3_noun bat)
   return 0;
 }
 
-/* _cj_boil_mine(): in boiling state, declare a core.  RETAINS.
+/* _cj_hot_mine(): in boiling state, declare a core.  RETAINS.
 */
 static c3_l
-_cj_boil_mine(u3_noun mop, u3_noun cor)
+_cj_hot_mine(u3_noun mop, u3_noun cor)
 {
   u3_noun p_mop, q_mop, r_mop, hr_mop, tr_mop;
 
@@ -417,7 +417,7 @@ _cj_boil_mine(u3_noun mop, u3_noun cor)
     }
     else par_l = 0;
 
-    return _cj_boil_mean(par_l, mop, u3h(cor));
+    return _cj_hot_mean(par_l, mop, u3h(cor));
   }
 }
 
@@ -498,7 +498,7 @@ _cj_warm_ream_at(u3_noun soh, u3_noun cag)
     }
     else par_l = 0;
 
-    jax_l = _cj_boil_mean(par_l, mop, 0);
+    jax_l = _cj_hot_mean(par_l, mop, 0);
    
     _cj_warm_ream_is(jax_l, q_mop, sab);
     return jax_l;
@@ -569,7 +569,7 @@ _cj_warm_mine(u3_noun clu, u3_noun cor)
       u3_noun mop;
 
       if ( u3_none != (mop = _cj_cold_mine(cey, cor)) ) {
-        c3_l jax_l = _cj_boil_mine(mop, cor);
+        c3_l jax_l = _cj_hot_mine(mop, cor);
 
         // fprintf(stderr, "warm: bat %x\r\n", u3r_mug(bat));
         u3h_put(u3R->jed.har_p, 
diff --git a/n/m.c b/n/m.c
index f5767e201..e4e52bb34 100644
--- a/n/m.c
+++ b/n/m.c
@@ -7,9 +7,75 @@
 #include <sys/stat.h>
 #include <ctype.h>
 #include <sigsegv.h>
+#include <pmmintrin.h>
+#include <xmmintrin.h>
 
 #include "all.h"
 
+      /* (u3_noun)setjmp(u3R->esc.buf): setjmp within road.
+      */
+#if 0
+        c3_o
+        u3m_trap(void);
+#else
+#       define u3m_trap() (u3_noun)(setjmp(u3R->esc.buf))
+#endif
+
+      /* u3m_signal(): treat a nock-level exception as a signal interrupt.
+      */
+        void
+        u3m_signal(u3_noun sig_l);
+
+      /* u3m_dump(): dump the current road to stderr.
+      */
+        void
+        u3m_dump(void);
+
+      /* u3m_mark(): mark all nouns in the road.
+      */
+        void
+        u3m_mark(void);
+
+      /* u3m_fall(): return to parent road.
+      */
+        void
+        u3m_fall(void);
+
+      /* u3m_leap(): in u3R, create a new road within the existing one.
+      */
+        void
+        u3m_leap(c3_w pad_w);
+
+      /* u3m_golf(): record cap length for u3_flog().
+      */
+        c3_w
+        u3m_golf(void);
+
+      /* u3m_flog(): pop the cap.
+      **
+      **    A common sequence for inner allocation is:
+      **
+      **    c3_w gof_w = u3m_golf();
+      **    u3m_leap();
+      **    //  allocate some inner stuff...
+      **    u3m_fall();
+      **    //  inner stuff is still valid, but on cap
+      **    u3m_flog(gof_w);
+      **
+      ** u3m_flog(0) simply clears the cap.
+      */
+        void
+        u3m_flog(c3_w gof_w);
+
+      /* u3m_soft_top(): top-level safety wrapper.
+      */
+        u3_noun 
+        u3m_soft_top(c3_w    sec_w,                     //  timer seconds
+                     c3_w    pad_w,                     //  base memory pad
+                     u3_funk fun_f,
+                     u3_noun arg);
+
+
 static jmp_buf u3_Signal;
 
 #ifndef SIGSTKSZ
@@ -294,7 +360,7 @@ _find_south(c3_w* mem_w, c3_w siz_w, c3_w len_w)
 #endif
 
 static u3_road*
-_boot_north(c3_w* mem_w, c3_w siz_w, c3_w len_w)
+_pave_north(c3_w* mem_w, c3_w siz_w, c3_w len_w)
 {
   c3_w*    rut_w = mem_w;
   c3_w*    hat_w = rut_w;
@@ -314,10 +380,10 @@ _boot_north(c3_w* mem_w, c3_w siz_w, c3_w len_w)
   return rod_u;
 }
 
-/* _boot_south(): install a south road.
+/* _pave_south(): install a south road.
 */
 static u3_road*
-_boot_south(c3_w* mem_w, c3_w siz_w, c3_w len_w)
+_pave_south(c3_w* mem_w, c3_w siz_w, c3_w len_w)
 {
   c3_w*    rut_w = (mem_w + len_w);
   c3_w*    hat_w = rut_w;
@@ -337,10 +403,10 @@ _boot_south(c3_w* mem_w, c3_w siz_w, c3_w len_w)
   return rod_u;
 }
 
-/* _boot_parts(): build internal tables.
+/* _pave_parts(): build internal tables.
 */
 static void
-_boot_parts(void)
+_pave_parts(void)
 {
   u3R->cax.har_p = u3h_new();
   u3R->jed.har_p = u3h_new();
@@ -362,18 +428,18 @@ u3m_mark(void)
   u3h_mark(u3R->cax.har_p);
 }
 
-/* u3m_boot(): instantiate or activate image.
+/* _cm_pave(): instantiate or activate image.
 */
-void
-u3m_boot(c3_o nuu_o, c3_o bug_o)
+static void
+_cm_pave(c3_o nuu_o, c3_o bug_o)
 {
   if ( c3y == nuu_o ) {
-    u3H = (void *)_boot_north(u3_Loom + 1, 
+    u3H = (void *)_pave_north(u3_Loom + 1, 
                               c3_wiseof(u3v_home), 
                               u3a_words - 1);
     u3R = &u3H->rod_u;
 
-    _boot_parts();
+    _pave_parts();
   } 
   else {
     u3H = (void *)_find_north(u3_Loom + 1, 
@@ -387,6 +453,7 @@ u3m_boot(c3_o nuu_o, c3_o bug_o)
   }
 }
 
+#if 0
 /* u3m_clear(): clear all allocated data in road.
 */
 void
@@ -397,7 +464,6 @@ u3m_clear(void)
   u3a_lose(u3R->jed.das);
 }
 
-#if 0
 void
 u3m_dump(void)
 {
@@ -578,7 +644,7 @@ u3m_leap(c3_w pad_w)
       bot_p = (u3R->cap_p - len_w);
       u3R->cap_p -= len_w;
 
-      rod_u = _boot_south(u3a_into(bot_p), c3_wiseof(u3a_road), len_w);
+      rod_u = _pave_south(u3a_into(bot_p), c3_wiseof(u3a_road), len_w);
 #if 0
       fprintf(stderr, "leap: from north %p (cap %x), to south %p\r\n",
               u3R,
@@ -590,7 +656,7 @@ u3m_leap(c3_w pad_w)
       bot_p = u3R->cap_p;
       u3R->cap_p += len_w;
 
-      rod_u = _boot_north(u3a_into(bot_p), c3_wiseof(u3a_road), len_w);
+      rod_u = _pave_north(u3a_into(bot_p), c3_wiseof(u3a_road), len_w);
 #if 0
       fprintf(stderr, "leap: from north %p (cap %p), to south %p\r\n",
               u3R,
@@ -615,7 +681,7 @@ u3m_leap(c3_w pad_w)
       rod_u->how.fag_w |= u3a_flag_debug;
     }
     u3R = rod_u;
-    _boot_parts();
+    _pave_parts();
   }
 }
 
@@ -755,7 +821,7 @@ u3m_soft_top(c3_w    sec_w,                     //  timer seconds
 
   /* Trap for ordinary nock exceptions.
   */
-  if ( 0 == (why = u3m_trap()) ) {
+  if ( 0 == (why = (u3_noun)setjmp(u3R->esc.buf)) ) {
     pro = fun_f(arg);
 
     /* Make sure the inner routine did not create garbage.
@@ -814,6 +880,15 @@ u3m_soft_slam(u3_noun gat, u3_noun sam)
   return u3m_soft_sure(_cm_slam, u3nc(gat, sam));
 }
 
+/* u3m_soft_nock: top-level nock.
+*/
+u3_noun _cm_nock(u3_noun arg) { return u3n_nock_on(u3h(arg), u3t(arg)); }
+u3_noun 
+u3m_soft_nock(u3_noun bus, u3_noun fol)
+{
+  return u3m_soft_sure(_cm_nock, u3nc(bus, fol));
+}
+
 /* u3m_soft_run(): descend into virtualization context.
 */
 u3_noun 
@@ -838,7 +913,7 @@ u3m_soft_run(u3_noun fly,
 
   /* Trap for exceptions.
   */
-  if ( 0 == (why = u3m_trap()) ) {
+  if ( 0 == (why = (u3_noun)setjmp(u3R->esc.buf)) ) {
     pro = fun_f(aga, agb);
 
     if ( u3R->how.fag_w & u3a_flag_debug ) {
@@ -926,7 +1001,7 @@ u3m_soft_esc(u3_noun sam)
 
   /* Trap for exceptions.
   */
-  if ( 0 == (why = u3m_trap()) ) {
+  if ( 0 == (why = (u3_noun)setjmp(u3R->esc.buf)) ) {
     pro = u3n_slam_on(fly, sam);
 
     /* Fall back to the old road, leaving temporary memory intact.
@@ -1189,3 +1264,180 @@ u3m_wall(u3_noun wol)
   }
   u3z(wol);
 }
+
+/* _cm_limits(): set up global modes and limits.
+*/
+static void
+_cm_limits(void)
+{
+  struct rlimit rlm;
+  c3_i          ret_i;
+
+  /* Set compatible floating-point modes.
+  */
+  {
+    _MM_SET_FLUSH_ZERO_MODE(_MM_FLUSH_ZERO_ON);
+    _MM_SET_DENORMALS_ZERO_MODE(_MM_DENORMALS_ZERO_ON);
+  }
+
+  /* Moar stack.
+  */
+  {
+    ret_i = getrlimit(RLIMIT_STACK, &rlm);
+    c3_assert(0 == ret_i);
+    rlm.rlim_cur = (rlm.rlim_max > (65536 << 10)) 
+                          ? (65536 << 10)
+                          : rlm.rlim_max;
+    if ( 0 != setrlimit(RLIMIT_STACK, &rlm) ) {
+      perror("stack");
+      exit(1);
+    }
+  }
+
+  /* Moar filez.
+  */
+  {
+    ret_i = getrlimit(RLIMIT_NOFILE, &rlm);
+    c3_assert(0 == ret_i);
+    rlm.rlim_cur = 4096;
+    if ( 0 != setrlimit(RLIMIT_NOFILE, &rlm) ) {
+      perror("file limit");
+      //  no exit, not a critical limit
+    }
+  }
+
+  /* Moar core.
+  */
+  {
+    getrlimit(RLIMIT_CORE, &rlm);
+    rlm.rlim_cur = RLIM_INFINITY;
+    if ( 0 != setrlimit(RLIMIT_CORE, &rlm) ) {
+      perror("core limit");
+      //  no exit, not a critical limit
+    }
+  }
+}
+
+/* _cm_signals(): set up interrupts, etc.
+*/
+static void
+_cm_signals(void)
+{
+  if ( 0 != sigsegv_install_handler(u3e_fault) ) {
+    fprintf(stderr, "sigsegv install failed\n");
+    exit(1);
+  }
+  // signal(SIGINT, _loom_stop);
+}
+
+/* _cm_init(): start the environment, with/without checkpointing.
+*/
+void
+_cm_init(c3_o chk_o)
+{
+  _cm_limits();
+  _cm_signals();
+
+  /* Make sure GMP uses our malloc.
+  */
+  mp_set_memory_functions(u3a_malloc, u3a_realloc2, u3a_free2);
+
+  /* Map at fixed address.
+  */
+  {
+    c3_w  len_w = u3a_bytes;
+    void* map_v;
+
+    map_v = mmap((void *)u3_Loom,
+                 len_w,
+                 _(chk_o) ? PROT_READ : (PROT_READ | PROT_WRITE),
+                 (MAP_ANON | MAP_FIXED | MAP_PRIVATE),
+                 -1, 0);
+
+    if ( -1 == (c3_ps)map_v ) {
+      map_v = mmap((void *)0,
+                   len_w,
+                   PROT_READ,
+                   MAP_ANON | MAP_PRIVATE,
+                   -1, 0);
+
+      if ( -1 == (c3_ps)map_v ) {
+        fprintf(stderr, "boot: map failed twice\r\n");
+      } else {
+        fprintf(stderr, "boot: map failed - try U3_OS_LoomBase %p\r\n", map_v);
+      }
+      exit(1);
+    }
+    printf("loom: mapped %dMB\r\n", len_w >> 20);
+  }
+}
+
+/* u3e_grab(): garbage-collect the world, plus extra roots, then 
+*/
+void
+u3e_grab(c3_c* cap_c, u3_noun som, ...)   // terminate with u3_none
+{
+  // u3h_free(u3R->cax.har_p);
+  // u3R->cax.har_p = u3h_new();
+
+  u3v_mark();
+  u3m_mark();
+  {
+    va_list vap;
+    u3_noun tur;
+
+    va_start(vap, som);
+
+    if ( som != u3_none ) {
+      u3a_mark_noun(som);
+
+      while ( u3_none != (tur = va_arg(vap, u3_noun)) ) {
+        u3a_mark_noun(tur);
+      }
+    }
+    va_end(vap);
+  }
+  u3a_sweep(cap_c);
+}
+
+/* u3m_boot(): start the u3 system.
+*/
+void
+u3m_boot(c3_o nuu_o, c3_o bug_o, c3_c* dir_c)
+{
+  /* Activate the loom.
+  */
+  _cm_init(nuu_o);
+
+  /* Activate the storage system.
+  */
+  u3e_live(nuu_o, dir_c);
+
+  /* Construct or activate the allocator.
+  */
+  _cm_pave(nuu_o, bug_o);
+
+  /* Initialize the jet system.
+  */
+  u3j_boot();
+
+  /* Install or reactivate the kernel.
+  */
+  if ( _(nuu_o) ) {
+    c3_c pas_c[2049];
+    struct stat buf_u;
+
+    snprintf(pas_c, 2048, "%s/.urb/urbit.pill", dir_c);
+    if ( -1 == stat(pas_c, &buf_u) ) {
+      snprintf(pas_c, 2048, "%s/urbit.pill", U3_LIB);
+    }
+    printf("boot: loading %s\r\n", pas_c);
+    u3v_make(pas_c);
+
+    u3v_jack();
+  }
+  else {
+    u3v_hose();
+    u3j_ream();
+  }
+}
diff --git a/v/main.c b/v/main.c
index 92199a84a..22990653a 100644
--- a/v/main.c
+++ b/v/main.c
@@ -164,7 +164,7 @@ _main_getopt(c3_i argc, c3_c** argv)
       }
     }
 
-    u3_Host.cpu_c = strdup(argv[optind]);
+    u3_Host.dir_c = strdup(argv[optind]);
     return c3y;
   }
 }
@@ -195,7 +195,7 @@ u3_ve_panic(c3_i argc, c3_c** argv)
 static void
 u3_ve_sysopt()
 {
-  u3_Local = strdup(u3_Host.cpu_c);
+  u3_Local = strdup(u3_Host.dir_c);
   u3_System = U3_LIB;
   u3_Flag_Abort = u3_Host.ops_u.abo;
   u3_Flag_Garbage = u3_Host.ops_u.gab;
@@ -294,7 +294,7 @@ main(c3_i   argc,
 
   printf("~\n");
   printf("welcome.\n");
-  printf("vere: urbit home is %s\n", u3_Host.cpu_c);
+  printf("vere: urbit home is %s\n", u3_Host.dir_c);
   printf("vere: hostname is %s\n", u3_Host.ops_u.nam_c);
 
   if ( c3y == u3_Host.ops_u.dem && c3n == u3_Host.ops_u.bat ) {
@@ -309,7 +309,7 @@ main(c3_i   argc,
   {
     /*  Boot the image and checkpoint.
     */
-    u3e_boot(u3_Host.ops_u.nuu, u3_Host.ops_u.gab, u3_Host.cpu_c);
+    u3m_boot(u3_Host.ops_u.nuu, u3_Host.ops_u.gab, u3_Host.dir_c);
 
     /*  Start Arvo.
     */
diff --git a/v/sist.c b/v/sist.c
index f2b95d308..753df3354 100644
--- a/v/sist.c
+++ b/v/sist.c
@@ -100,7 +100,7 @@ u3_sist_put(const c3_c* key_c, const c3_y* val_y, size_t siz_i)
   c3_i ret_i;
   c3_i fid_i;
 
-  ret_i = snprintf(ful_c, 2048, "%s/.urb/sis/_%s", u3_Host.cpu_c, key_c);
+  ret_i = snprintf(ful_c, 2048, "%s/.urb/sis/_%s", u3_Host.dir_c, key_c);
   c3_assert(ret_i < 2048);
 
   if ( (fid_i = open(ful_c, O_CREAT | O_TRUNC | O_WRONLY, 0600)) < 0 ) {
@@ -132,7 +132,7 @@ u3_sist_has(const c3_c* key_c)
   c3_i        ret_i;
   struct stat sat_u;
 
-  ret_i = snprintf(ful_c, 2048, "%s/.urb/sis/_%s", u3_Host.cpu_c, key_c);
+  ret_i = snprintf(ful_c, 2048, "%s/.urb/sis/_%s", u3_Host.dir_c, key_c);
   c3_assert(ret_i < 2048);
 
   if ( (ret_i = stat(ful_c, &sat_u)) < 0 ) {
@@ -161,7 +161,7 @@ u3_sist_get(const c3_c* key_c, c3_y* val_y)
   c3_i        fid_i;
   struct stat sat_u;
 
-  ret_i = snprintf(ful_c, 2048, "%s/.urb/sis/_%s", u3_Host.cpu_c, key_c);
+  ret_i = snprintf(ful_c, 2048, "%s/.urb/sis/_%s", u3_Host.dir_c, key_c);
   c3_assert(ret_i < 2048);
 
   if ( (fid_i = open(ful_c, O_RDONLY)) < 0 ) {
@@ -193,7 +193,7 @@ u3_sist_nil(const c3_c* key_c)
   c3_c ful_c[2048];
   c3_i ret_i;
 
-  ret_i = snprintf(ful_c, 2048, "%s/.urb/sis/_%s", u3_Host.cpu_c, key_c);
+  ret_i = snprintf(ful_c, 2048, "%s/.urb/sis/_%s", u3_Host.dir_c, key_c);
   c3_assert(ret_i < 2048);
 
   if ( (ret_i = unlink(ful_c)) < 0 ) {
@@ -281,24 +281,24 @@ _sist_home()
   //  Create subdirectories.
   //
   {
-    mkdir(u3_Host.cpu_c, 0700);
+    mkdir(u3_Host.dir_c, 0700);
 
-    snprintf(ful_c, 2048, "%s/.urb", u3_Host.cpu_c);
+    snprintf(ful_c, 2048, "%s/.urb", u3_Host.dir_c);
     mkdir(ful_c, 0700);
 
-    snprintf(ful_c, 2048, "%s/.urb/get", u3_Host.cpu_c);
+    snprintf(ful_c, 2048, "%s/.urb/get", u3_Host.dir_c);
     if ( 0 != mkdir(ful_c, 0700) ) {
       perror(ful_c);
       u3_lo_bail();
     }
 
-    snprintf(ful_c, 2048, "%s/.urb/put", u3_Host.cpu_c);
+    snprintf(ful_c, 2048, "%s/.urb/put", u3_Host.dir_c);
     if ( 0 != mkdir(ful_c, 0700) ) {
       perror(ful_c);
       u3_lo_bail();
     }
 
-    snprintf(ful_c, 2048, "%s/.urb/sis", u3_Host.cpu_c);
+    snprintf(ful_c, 2048, "%s/.urb/sis", u3_Host.dir_c);
     if ( 0 != mkdir(ful_c, 0700) ) {
       perror(ful_c);
       u3_lo_bail();
@@ -309,7 +309,7 @@ _sist_home()
   //
   {
     snprintf(ful_c, 2048, "cp %s/urbit.pill %s/.urb",
-                    U3_LIB, u3_Host.cpu_c);
+                    U3_LIB, u3_Host.dir_c);
     printf("%s\r\n", ful_c);
     if ( 0 != system(ful_c) ) {
       uL(fprintf(uH, "could not %s\n", ful_c));
@@ -322,7 +322,7 @@ _sist_home()
   //
   if ( u3_Host.ops_u.imp_c ) {
     snprintf(ful_c, 2048, "cp -r %s/zod %s/%s",
-                    U3_LIB, u3_Host.cpu_c, u3_Host.ops_u.imp_c+1);
+                    U3_LIB, u3_Host.dir_c, u3_Host.ops_u.imp_c+1);
     printf("%s\r\n", ful_c);
     if ( 0 != system(ful_c) ) {
       uL(fprintf(uH, "could not %s\n", ful_c));
@@ -464,7 +464,7 @@ static void
 _sist_fast(u3_noun pas, c3_l key_l)
 {
   c3_c    ful_c[2048];
-  c3_c*   hom_c = u3_Host.cpu_c;
+  c3_c*   hom_c = u3_Host.dir_c;
   u3_noun gum   = u3dc("scot", 'p', key_l);
   c3_c*   gum_c = u3r_string(gum);
   u3_noun yek   = u3dc("scot", 'p', pas);
@@ -496,7 +496,7 @@ static u3_noun
 _sist_staf(c3_l key_l)
 {
   c3_c    ful_c[2048];
-  c3_c*   hom_c = u3_Host.cpu_c;
+  c3_c*   hom_c = u3_Host.dir_c;
   u3_noun gum   = u3dc("scot", 'p', key_l);
   c3_c*   gum_c = u3r_string(gum);
   u3_noun txt;
@@ -568,7 +568,7 @@ _sist_zest()
 #ifdef O_DSYNC
     pig_i |= O_DSYNC;
 #endif
-    snprintf(ful_c, 2048, "%s/.urb/egz.hope", u3_Host.cpu_c);
+    snprintf(ful_c, 2048, "%s/.urb/egz.hope", u3_Host.dir_c);
 
     if ( ((fid_i = open(ful_c, pig_i, 0600)) < 0) ||
          (fstat(fid_i, &buf_b) < 0) )
@@ -731,7 +731,7 @@ _sist_rest_nuu(u3_ulog* lug_u, u3_uled led_u, c3_c* old_c)
     u3_lo_bail();
   }
 
-  ret_i = snprintf(nuu_c, 2048, "%s/.urb/ham.hope", u3_Host.cpu_c);
+  ret_i = snprintf(nuu_c, 2048, "%s/.urb/ham.hope", u3_Host.dir_c);
   c3_assert(ret_i < 2048);
 
   if ( (fud_i = open(nuu_c, O_CREAT | O_TRUNC | O_RDWR, 0600)) < 0 ) {
@@ -834,7 +834,7 @@ _sist_rest()
 #ifdef O_DSYNC
     pig_i |= O_DSYNC;
 #endif
-    snprintf(ful_c, 2048, "%s/.urb/egz.hope", u3_Host.cpu_c);
+    snprintf(ful_c, 2048, "%s/.urb/egz.hope", u3_Host.dir_c);
     if ( ((fid_i = open(ful_c, pig_i)) < 0) || (fstat(fid_i, &buf_b) < 0) ) {
       uL(fprintf(uH, "rest: can't open record (%s)\n", ful_c));
       u3_lo_bail();
@@ -904,7 +904,7 @@ _sist_rest()
       u3_noun key;
 
       while ( 1 ) {
-        pas = pas ? pas : _sist_cask(u3_Host.cpu_c, c3n);
+        pas = pas ? pas : _sist_cask(u3_Host.dir_c, c3n);
 
         key = _sist_fatt(sal_l, pas);
 
@@ -1123,9 +1123,9 @@ _sist_rest()
     c3_c*   fil_c;
     c3_c*   who_c;
 
-    if ( (fil_c = strrchr(u3_Host.cpu_c, '/')) ) {
+    if ( (fil_c = strrchr(u3_Host.dir_c, '/')) ) {
       fil_c++;
-    } else fil_c = u3_Host.cpu_c;
+    } else fil_c = u3_Host.dir_c;
 
     who = u3dc("scot", 'p', u3k(u3A->our)));
     who_c = u3r_string(who);
@@ -1219,7 +1219,7 @@ u3_sist_boot(void)
 
     if ( 0 == u3_Host.ops_u.imp_c ) {
       c3_c get_c[2049];
-      snprintf(get_c, 2048, "%s/.urb/get", u3_Host.cpu_c);
+      snprintf(get_c, 2048, "%s/.urb/get", u3_Host.dir_c);
       if ( 0 == access(get_c, 0) ) {
           uL(fprintf(uH, "pier: already built\n"));
           u3_lo_bail();
diff --git a/v/term.c b/v/term.c
index 269fe53f1..06017d494 100644
--- a/v/term.c
+++ b/v/term.c
@@ -617,7 +617,7 @@ _term_it_path(u3_noun fyl, u3_noun pax)
 
   //  measure
   //
-  len_w = strlen(u3_Host.cpu_c);
+  len_w = strlen(u3_Host.dir_c);
   {
     u3_noun wiz = pax;
 
@@ -630,7 +630,7 @@ _term_it_path(u3_noun fyl, u3_noun pax)
   //  cut
   //
   pas_c = c3_malloc(len_w + 1);
-  strncpy(pas_c, u3_Host.cpu_c, len_w);
+  strncpy(pas_c, u3_Host.dir_c, len_w);
   pas_c[len_w] = '\0';
   {
     u3_noun wiz   = pax;
diff --git a/v/unix.c b/v/unix.c
index 580c08cbd..703e62df5 100644
--- a/v/unix.c
+++ b/v/unix.c
@@ -1026,7 +1026,7 @@ _unix_hot_gain(u3_noun who, u3_noun mek)
 {
   u3_noun hox = u3dc("scot", 'p', u3k(who));
   c3_c*   hox_c = u3r_string(hox);
-  c3_c*   pax_c = _unix_down(u3_Host.cpu_c, hox_c + 1);
+  c3_c*   pax_c = _unix_down(u3_Host.dir_c, hox_c + 1);
   DIR*    rid_u = opendir(pax_c);
 
   if ( !rid_u ) {
@@ -1527,7 +1527,7 @@ u3_unix_io_init(void)
 void
 u3_unix_io_talk()
 {
-  u3_unix_acquire(u3_Host.cpu_c);
+  u3_unix_acquire(u3_Host.dir_c);
   u3_unix_ef_move();
   uv_check_start(&u3_Host.unx_u.syn_u, _unix_ef_sync);
 }
@@ -1538,7 +1538,7 @@ void
 u3_unix_io_exit(void)
 {
   uv_check_stop(&u3_Host.unx_u.syn_u);
-  u3_unix_release(u3_Host.cpu_c);
+  u3_unix_release(u3_Host.dir_c);
 
   {
     u3_uhot* hot_u;