diff --git a/pkg/urbit/daemon/main.c b/pkg/urbit/daemon/main.c
index 02f69acf8a..657d1c2ac5 100644
--- a/pkg/urbit/daemon/main.c
+++ b/pkg/urbit/daemon/main.c
@@ -93,10 +93,11 @@ _main_getopt(c3_i argc, c3_c** argv)
   u3_Host.ops_u.tex = c3n;
   u3_Host.ops_u.tra = c3n;
   u3_Host.ops_u.veb = c3n;
+  u3_Host.ops_u.hap_w = 50000;
   u3_Host.ops_u.kno_w = DefaultKernel;
 
   while ( -1 != (ch_i=getopt(argc, argv,
-                 "G:J:B:K:A:H:I:w:u:e:F:k:p:LljacdgqstvxPDRS")) )
+                 "G:J:B:K:A:H:I:C:w:u:e:F:k:p:LljacdgqstvxPDRS")) )
   {
     switch ( ch_i ) {
       case 'J': {
@@ -123,6 +124,12 @@ _main_getopt(c3_i argc, c3_c** argv)
         u3_Host.ops_u.jin_c = strdup(optarg);
         break;
       }
+      case 'C': {
+        if ( c3n == _main_readw(optarg, 1000000000, &u3_Host.ops_u.hap_w) ) {
+          return c3n;
+        }
+        break;
+      }
       case 'e': {
         u3_Host.ops_u.eth_c = strdup(optarg);
         break;
@@ -367,9 +374,9 @@ u3_ve_usage(c3_i argc, c3_c** argv)
     "where ship_name is a @p phonetic representation of an urbit address\n",
     "without the leading '~', and options is some subset of the following:\n",
     "\n",
-    // XX find a way to re-enable
-    // "-A dir        Use dir for initial galaxy sync\n",
+    "-A dir        Use dir for initial clay sync\n",
     "-B pill       Bootstrap from this pill\n",
+    "-C limit      Set memo cache max size; 0 means uncapped\n",
     "-c pier       Create a new urbit in pier/\n",
     "-D            Recompute from events\n",
     "-d            Daemon mode; implies -t\n",
diff --git a/pkg/urbit/include/vere/vere.h b/pkg/urbit/include/vere/vere.h
index f8e5452197..41a539b803 100644
--- a/pkg/urbit/include/vere/vere.h
+++ b/pkg/urbit/include/vere/vere.h
@@ -559,6 +559,7 @@
         c3_o    gab;                        //  -g, test garbage collection
         c3_c*   dns_c;                      //  -H, ames bootstrap domain
         c3_c*   jin_c;                      //  -I, inject raw event
+        c3_w    hap_w;                      //  -C, cap memo cache
         c3_c*   lit_c;                      //  -J, ivory (fastboot) kernel
         c3_o    tra;                        //  -j, json trace
         c3_w    kno_w;                      //  -K, kernel version
diff --git a/pkg/urbit/noun/manage.c b/pkg/urbit/noun/manage.c
index b4c1968cbb..f5127be741 100644
--- a/pkg/urbit/noun/manage.c
+++ b/pkg/urbit/noun/manage.c
@@ -10,6 +10,7 @@
 #include <openssl/crypto.h>
 
 #include "all.h"
+#include "vere/vere.h"
 
 //  XX stack-overflow recovery should be gated by -a
 //
@@ -496,7 +497,7 @@ _pave_south(c3_w* mem_w, c3_w siz_w, c3_w len_w)
 static void
 _pave_parts(void)
 {
-  u3R->cax.har_p = u3h_new_cache(50000);
+  u3R->cax.har_p = u3h_new_cache(u3_Host.ops_u.hap_w);
   u3R->jed.war_p = u3h_new();
   u3R->jed.cod_p = u3h_new();
   u3R->jed.han_p = u3h_new();
diff --git a/pkg/urbit/vere/pier.c b/pkg/urbit/vere/pier.c
index fff3f15581..0c5b114422 100644
--- a/pkg/urbit/vere/pier.c
+++ b/pkg/urbit/vere/pier.c
@@ -1039,11 +1039,12 @@ _pier_work_create(u3_pier* pir_u)
   /* spawn new process and connect to it
   */
   {
-    c3_c* arg_c[5];
+    c3_c* arg_c[6];
     c3_c* bin_c = u3_Host.wrk_c;
     c3_c* pax_c = pir_u->pax_c;
     c3_c  key_c[256];
     c3_c  wag_c[11];
+    c3_c  hap_c[11];
     c3_i  err_i;
 
     sprintf(key_c, "%" PRIx64 ":%" PRIx64 ":%" PRIx64 ":%" PRIx64 "",
@@ -1053,12 +1054,14 @@ _pier_work_create(u3_pier* pir_u)
                    pir_u->key_d[3]);
 
     sprintf(wag_c, "%u", pir_u->wag_w);
+    sprintf(hap_c, "%u", u3_Host.ops_u.hap_w);
 
     arg_c[0] = bin_c;                   //  executable
     arg_c[1] = pax_c;                   //  path to checkpoint directory
     arg_c[2] = key_c;                   //  disk key
     arg_c[3] = wag_c;                   //  runtime config
-    arg_c[4] = 0;
+    arg_c[4] = hap_c;                   //  hash table size
+    arg_c[5] = 0;
 
     uv_pipe_init(u3L, &god_u->inn_u.pyp_u, 0);
     uv_pipe_init(u3L, &god_u->out_u.pyp_u, 0);
diff --git a/pkg/urbit/worker/main.c b/pkg/urbit/worker/main.c
index d3148773b1..064029a6c1 100644
--- a/pkg/urbit/worker/main.c
+++ b/pkg/urbit/worker/main.c
@@ -1015,8 +1015,9 @@ main(c3_i argc, c3_c* argv[])
   c3_c*      dir_c = argv[1];
   c3_c*      key_c = argv[2];
   c3_c*      wag_c = argv[3];
+  c3_c*      hap_c = argv[4];
 
-  c3_assert(4 == argc);
+  c3_assert(5 == argc);
 
   memset(&u3V, 0, sizeof(u3V));
   memset(&u3_Host.tra_u, 0, sizeof(u3_Host.tra_u));
@@ -1035,6 +1036,7 @@ main(c3_i argc, c3_c* argv[])
   */
   {
     sscanf(wag_c, "%" SCNu32, &u3C.wag_w);
+    sscanf(hap_c, "%" SCNu32, &u3_Host.ops_u.hap_w);
   }
 
   /* load pier directory