diff --git a/prospect/ground.rkt b/prospect/ground.rkt
index 2a3b6c4..8e34f32 100644
--- a/prospect/ground.rkt
+++ b/prospect/ground.rkt
@@ -6,6 +6,7 @@
 (require racket/match)
 (require racket/list)
 (require "core.rkt")
+(require "trace.rkt")
 (require "trace/stderr.rkt")
 
 (provide (struct-out external-event)
@@ -77,7 +78,10 @@
                         (current-ground-event-async-channel)
                         (if inert? never-evt idle-handler)
                         (extract-active-events interests))))
-	  (match (clean-transition (world-handle-event e w))
+          (trace-process-step e #f world-handle-event w)
+          (define resulting-transition (clean-transition (world-handle-event e w)))
+          (trace-process-step-result e #f world-handle-event w #f resulting-transition)
+	  (match resulting-transition
 	    [#f ;; inert
 	     (await-interrupt #t w interests)]
 	    [(transition w actions)
diff --git a/prospect/trace.rkt b/prospect/trace.rkt
index 08f2170..2ef29f2 100644
--- a/prospect/trace.rkt
+++ b/prospect/trace.rkt
@@ -34,25 +34,30 @@
   (when (log-level? trace-logger 'info)
     (log-message trace-logger 'info name "" r #f)))
 
-;; Event PID Process -> Void
-(define (trace-process-step e pid beh st)
-  (record-trace-event 'process-step (list (cons pid (trace-pid-stack)) e beh st)))
+(define (cons-pid pid)
+  (if pid
+      (cons pid (trace-pid-stack))
+      (trace-pid-stack)))
 
-;; Event PID Process (Option Exception) (Option Transition) -> Void
+;; Event (Option PID) Process -> Void
+(define (trace-process-step e pid beh st)
+  (record-trace-event 'process-step (list (cons-pid pid) e beh st)))
+
+;; Event (Option PID) Process (Option Exception) (Option Transition) -> Void
 (define (trace-process-step-result e pid beh st exn t)
   (when exn
     (log-error "Process ~a died with exception:\n~a"
-	       (cons pid (trace-pid-stack))
+	       (cons-pid pid)
 	       (exn->string exn)))
-  (record-trace-event 'process-step-result (list (cons pid (trace-pid-stack)) e beh st exn t)))
+  (record-trace-event 'process-step-result (list (cons-pid pid) e beh st exn t)))
 
-;; PID Action World -> Void
+;; (Option PID) Action World -> Void
 (define (trace-internal-action pid a w)
-  (record-trace-event 'internal-action (list (cons pid (trace-pid-stack)) a w)))
+  (record-trace-event 'internal-action (list (cons-pid pid) a w)))
 
-;; PID Action World Transition -> Void
+;; (Option PID) Action World Transition -> Void
 (define (trace-internal-action-result pid a w t)
-  (record-trace-event 'internal-action-result (list (cons pid (trace-pid-stack)) a w t)))
+  (record-trace-event 'internal-action-result (list (cons-pid pid) a w t)))
 
 (define (string-indent amount s)
   (define pad (make-string amount #\space))
diff --git a/prospect/trace/stderr.rkt b/prospect/trace/stderr.rkt
index e859d4b..e4eb6fc 100644
--- a/prospect/trace/stderr.rkt
+++ b/prospect/trace/stderr.rkt
@@ -33,6 +33,7 @@
 (define show-message-actions? #f)
 (define show-actions? #f)
 (define show-routing-table? #f)
+(define world-is-boring? #t)
 
 (define (set-stderr-trace-flags! flags-string)
   (set! flags (for/set [(c flags-string)] (string->symbol (string c))))
@@ -46,7 +47,8 @@
   (set! show-patch-actions? (set-member? flags 'R))
   (set! show-message-actions? (set-member? flags 'M))
   (set! show-actions? (set-member? flags 'a))
-  (set! show-routing-table? (set-member? flags 'g)))
+  (set! show-routing-table? (set-member? flags 'g))
+  (set! world-is-boring? (not (set-member? flags 'W))))
 
 (set-stderr-trace-flags! (or (getenv "MINIMART_TRACE") ""))
 
@@ -75,11 +77,11 @@
 
 (define (output-state state)
   (cond
-   [(world? state) (output "#<world>\n")]
+   [(world? state) (pretty-print-world state)]
    [else (pretty-write state (current-error-port))]))
 
 (define (boring-state? state)
-  (or (world? state)
+  (or (and (world? state) world-is-boring?)
       (void? state)))
 
 (define (set-color! c) (when colored-output? (output "\e[0~am" c)))