diff --git a/core/actor.lisp b/core/actor.lisp
index 473c31f..2a44b2f 100644
--- a/core/actor.lisp
+++ b/core/actor.lisp
@@ -61,7 +61,7 @@
   (let ((*self* tsk))
     (handler-case (funcall bhv msg)
       (error (err) 
-             (util:lg :error "behavior" msg err))
+             (util:lg :error "behavior" msg tsk bhv err))
              ;(invoke-debugger err))
       )))
 
diff --git a/csys/csys.lisp b/csys/csys.lisp
index 76c5ea7..cc3164f 100644
--- a/csys/csys.lisp
+++ b/csys/csys.lisp
@@ -47,7 +47,18 @@
   scope)
 
 (defgeneric make-program (spec)
-  (:method ((fn function)) (lambda (scp) fn)))
+  (:method ((proc function)) (lambda (scp) proc))
+  (:method ((spec hash-table))
+    (lambda (scp)
+      (let* ((cat (cadr (categ scp)))
+             (stg (stage scp))
+             (proc (gethash (list cat stg) spec
+                     (gethash (list cat :default) spec
+                       (gethash (list :default stg) spec
+                         (gethash :default spec))))))
+        (unless proc
+          (util:lgw "proc not found" cat stg spec))
+        proc))))
 
 (defun create-zero (prg env &key (categ '(:csys :c00)) (name "0-0"))
   (let* ((domain (car categ))
@@ -72,7 +83,8 @@
 ;;;; message handlers, proc steps
 
 (defun process (scope)
-  (lambda (msg) (funcall (proc scope) msg scope)))
+  (lambda (msg) 
+    (funcall (proc scope) msg scope)))
 
 (defun std-proc (&key (default (remember)) actions)
   (lambda (msg scope) 
@@ -111,7 +123,8 @@
 
 (defun basic-actions ()
   (list :value (value-add)
-        :create (create)))
+        :create (create)
+        :next (no-op :no-forward t)))
  
 (defun no-op (&key no-forward) 
   (lambda (msg scope) 
@@ -141,6 +154,8 @@
       (notify-created msg new scope)
       nil)))
 
+;;;; synapse ops
+
 ;;;; helpers
 
 (defun new-msg-head (msg scope)
diff --git a/csys/environ.lisp b/csys/environ.lisp
index c3f6be3..6277ea3 100644
--- a/csys/environ.lisp
+++ b/csys/environ.lisp
@@ -36,7 +36,9 @@
          (new (getf data :new)))
     (when addr
       (register-cell (cells scope) addr new))
-    ;send startup message / create more cells
+    ;;;send :next message / create more cells:
+    ;(actor:send new 
+    ;  (message:create (list (message:domain msg) :next) :data (shape:data msg))
     msg))
 
 (defun forward (msg scope)
diff --git a/test/test-csys.lisp b/test/test-csys.lisp
index 25fa587..c91da83 100644
--- a/test/test-csys.lisp
+++ b/test/test-csys.lisp
@@ -60,11 +60,21 @@
     (csys:create-zero prg env)
     env))
 
-(defun actions () (csys:basic-actions))
+(defun test-program ()
+  (csys:make-program (csys:eff-proc :actions (actions-zero))))
+
+(defun next-zero ()
+  (lambda (msg scope) 
+    (util:lgi msg)
+    nil))
+
+(defun actions-zero () 
+  (let ((acts (csys:basic-actions)))
+    (setf (getf acts :next) (next-zero))
+    acts))
  
 (deftest test-basic-0 ()
-  (let ((env (setup-test (csys:make-program (csys:eff-proc :actions (actions)))))
-        ;(env (setup-test (test-program))
+  (let ((env (setup-test (test-program)))
         (rcvr (tc:receiver t:*test-suite*)))
     (sleep 0.1)
     (tc:expect rcvr (message:create '(:csys :effect :c00) :data '(:value 1)))