diff --git a/pkg/arvo/sys/hoon.hoon b/pkg/arvo/sys/hoon.hoon
index 43dc11b615..b259b1ed04 100644
--- a/pkg/arvo/sys/hoon.hoon
+++ b/pkg/arvo/sys/hoon.hoon
@@ -1619,6 +1619,7 @@
     [-.f a(l +.e, r +.f)]
   ::
   ++  run                                               ::  apply gate to values
+    ~/  %run
     |*  b/gate
     |-
     ?~  a  a
diff --git a/pkg/urbit/include/jets/w.h b/pkg/urbit/include/jets/w.h
index 98d8e07db3..c63026a192 100644
--- a/pkg/urbit/include/jets/w.h
+++ b/pkg/urbit/include/jets/w.h
@@ -89,6 +89,7 @@
     u3_noun u3wdb_put(u3_noun);
 #   define u3wdb_tap u3wdi_tap
     u3_noun u3wdb_uni(u3_noun);
+    u3_noun u3wdb_run(u3_noun);
 
     u3_noun u3wdi_bif(u3_noun);
     u3_noun u3wdi_del(u3_noun);
diff --git a/pkg/urbit/jets/d/by_run.c b/pkg/urbit/jets/d/by_run.c
new file mode 100644
index 0000000000..6fd2d2cf87
--- /dev/null
+++ b/pkg/urbit/jets/d/by_run.c
@@ -0,0 +1,38 @@
+/* j/4/by_run.c
+**
+*/
+#include "all.h"
+
+/* internal functions
+ */
+static u3_noun
+_by_run(u3_noun a, u3j_site* sit_u)
+{
+  if (u3_nul == a) {
+    return 0;
+  } else {
+    u3_noun n_a, l_a, r_a;
+    u3_noun p_n_a, q_n_a;
+    u3x_trel(a, &n_a, &l_a, &r_a);
+    u3x_cell(n_a, &p_n_a, &q_n_a);
+
+    u3_noun nu_q_n_a = u3j_gate_slam(sit_u, u3k(q_n_a));
+    u3_noun nu_l = _by_run(l_a, sit_u);
+    u3_noun nu_r = _by_run(r_a, sit_u);
+    return u3nt(u3nc(u3k(p_n_a), nu_q_n_a), nu_l, nu_r);
+  }
+}
+
+u3_noun
+u3wdb_run(u3_noun cor)
+{
+  u3_noun a, b;
+  u3j_site sit_u;
+
+  u3x_mean(cor, u3x_sam, &b, u3x_con_sam, &a, 0);
+
+  u3j_gate_prep(&sit_u, u3k(b));
+  u3_noun pro = _by_run(a, &sit_u);
+  u3j_gate_lose(&sit_u);
+  return pro;
+}
diff --git a/pkg/urbit/jets/tree.c b/pkg/urbit/jets/tree.c
index 43c266a960..283fae8191 100644
--- a/pkg/urbit/jets/tree.c
+++ b/pkg/urbit/jets/tree.c
@@ -1635,6 +1635,9 @@ static c3_c* _141_two__in_ha[] = {
     "2cc9f005fde5314e9ad545286493a8c81b5c3b775d645ad82954f405d9414a32",
     0
   };
+
+  static u3j_harm _141_two__by_run_a[] = {{".2", u3wdb_run, c3y}, {}};
+
   static u3j_harm _141_two__by_tap_a[] = {{".2", u3wdb_tap, c3y}, {}};
   static c3_c* _141_two__by_tap_ha[] = {
     "7dde59e2bd7684e785ce9787bc394571bd1216d7a62398c703447fc951c6b352",
@@ -1655,6 +1658,7 @@ static u3j_core _141_two__by_d[] =
     // { "int", 7, _141_two__by_int_a, 0, _141_two__by_int_ha },
     { "jab", 7, _141_two__by_jab_a, 0, _141_two__by_jab_ha },
     { "put", 7, _141_two__by_put_a, 0, _141_two__by_put_ha },
+    { "run", 7, _141_two__by_run_a },
     { "tap", 7, _141_two__by_tap_a, 0, _141_two__by_tap_ha },
     // { "uni", 7, _141_two__by_uni_a, 0, _141_two__by_uni_ha },
     {}