diff --git a/csys/csys.lisp b/csys/csys.lisp
index d701b81..0a20a1a 100644
--- a/csys/csys.lisp
+++ b/csys/csys.lisp
@@ -29,39 +29,39 @@
 ;(defvar *environment* (make-instance 'environment))
 (defvar *environment* nil)
 
-(defun add-action (key fn &optional (env *environment*))
-  ;(util:lgi key fn env)
-  (setf (gethash key (actions env)) fn))
+(defun add-action (key fn)
+  ;(util:lgi key fn *environment*)
+  (setf (gethash key (actions *environment*)) fn))
 
-(defun add-sensors (key sns &optional (env *environment*))
-  ;(util:lgi key sns env)
-  (setf (gethash key (sensors env)) sns))
+(defun add-sensors (key sns)
+  ;(util:lgi key sns *environment*)
+  (setf (gethash key (sensors *environment*)) sns))
 
 ;;;; neurons (= behavior factories) and synapses (connection factories)
 
 (defun neuron (proc &optional state syns (env *environment*))
   (lambda (msg) 
-    (funcall proc msg state syns env)))
+    (let ((*environment* env)) 
+      (funcall proc msg state syns))))
 
 (defun synapse (rcvr &optional (op #'identity))
   (lambda (msg)
     (actor:send rcvr (funcall op msg))))
 
-(defun make-neuron (syn-target &key proc state 
-                                    (syn-op #'identity) (env *environment*))
-  (let ((proc (or proc (gethash :default (procs env) #'std-proc)))
+(defun make-neuron (syn-target &key proc state (syn-op #'identity))
+  (let ((proc (or proc (gethash :default (procs *environment*) #'std-proc)))
         (syns (if syn-target (list (synapse syn-target syn-op)) nil)))
-    (actor:create (neuron proc state syns env))))
+    (actor:create (neuron proc state syns))))
 
-(defun update-neuron (proc state syns &optional (env *environment*))
-  (actor:become (neuron proc state syns env)))
+(defun update-neuron (proc state syns)
+  (actor:become (neuron proc state syns)))
 
-(defun std-proc (msg state syns env)
+(defun std-proc (msg state syns)
   ;(util:lgi msg state syns env)
   (destructuring-bind (nmsg nst nsyns) 
-        (handle-action msg state syns env :default #'remember)
+        (handle-action msg state syns :default #'remember)
     (forward nmsg nsyns)
-    (update-neuron (next-proc nst) nst nsyns env)))
+    (update-neuron (next-proc nst) nst nsyns)))
 
 ;;;; neuron state methods
 
@@ -88,7 +88,7 @@
 
 ;;;; effector procs for pseudo-neurons embedded in environment
 
-(defun do-log (msg state syns env)
+(defun do-log (msg state syns)
   (util:lgi msg))
 
 ;;;; helper / utility funtions
@@ -97,28 +97,27 @@
   (dolist (s syns) 
     (funcall s msg)))
 
-(defun handle-action (msg state syns env &key (default #'no-op))
+(defun handle-action (msg state syns &key (default #'no-op))
   (let* ((key (shape:head-value msg :action))
-         (act (gethash key (actions env) default)))
-    (funcall act msg state syns env)))
+         (act (gethash key (actions *environment*) default)))
+    (funcall act msg state syns)))
 
 ;;;; predefined neuron actions
 
-(defun no-op (msg state syns env)
+(defun no-op (msg state syns)
   (list msg state syns))
 
-(defun remember (msg state syns env)
+(defun remember (msg state syns)
   ;(list msg (make-neuron-state (shape:data msg) syns))
   (list msg (shape:data msg) syns))
  
-(defun create-sensor (msg state syns env)
+(defun create-sensor (msg state syns)
   (let* ((key (shape:data msg))
-         (sensor (make-neuron actor:*self* :state key :env env))
+         (sensor (make-neuron actor:*self* :state key))
          (nmsg (message:create (list :csys :created (car key) (cadr key)))))
-    ;(setf (gethash key (sensors env)) (list sensor))
-    (add-sensors key (list sensor) env)
+    (add-sensors key (list sensor))
     (list nmsg state syns)))
 
-(defun add (msg state syns env)
+(defun add (msg state syns)
   (list msg (+ (shape:data msg) state) syns))
  
diff --git a/test/test-csys.lisp b/test/test-csys.lisp
index 43a90e3..22fde32 100644
--- a/test/test-csys.lisp
+++ b/test/test-csys.lisp
@@ -36,10 +36,10 @@
   (config:add-action '(:csys) (constantly nil))
   )
 
-(defun eff-proc (msg state syns env)
-  (let ((t:*test-suite* (test-suite env))) 
+(defun eff-proc (msg state syns)
+  (let ((t:*test-suite* (test-suite csys:*environment*))) 
     (destructuring-bind (nmsg nst nsyns) 
-          (csys:handle-action msg state syns env)
+          (csys:handle-action msg state syns)
       (util:lgi nmsg)
       (actor:send (core:mailbox (tc:receiver t:*test-suite*)) nmsg))))