diff --git a/nullptr/analyzer.py b/nullptr/analyzer.py
index 2b148cd..9a966a9 100644
--- a/nullptr/analyzer.py
+++ b/nullptr/analyzer.py
@@ -165,7 +165,7 @@ def prices(c, system):
 
 def find_trade(c, system):
   max_traders = 3
-  prices = prices(system)
+  pcs= prices(c, system)
   occupied_routes = dict()
   for s in c.store.all('Ship'):
     if s.mission != 'trade':
@@ -176,7 +176,7 @@ def find_trade(c, system):
     else:
       occupied_routes[k] = 1
   best = None
-  for resource, markets in prices.items():
+  for resource, markets in pcs.items():
     source = sorted(markets, key=lambda x: x['buy'])[0]
     dest = sorted(markets, key=lambda x: x['sell'])[-1]
     swp = source['wp']
diff --git a/nullptr/commander.py b/nullptr/commander.py
index de653a2..88066b2 100644
--- a/nullptr/commander.py
+++ b/nullptr/commander.py
@@ -139,7 +139,7 @@ class Commander(CommandLine):
     symbol = input('agent name: ')
     agent = self.store.get(Agent, symbol, create=True)
     self.agent = agent
-    api = Api(self.store, agent)
+    api = Api(self.c, agent)
     self.api = api
     faction = input('faction or token: ')
     if len(faction) > 50:
@@ -571,3 +571,9 @@ class Commander(CommandLine):
     w = self.resolve('Waypoint', waypoint_str)
     p = find_nav_path(self.c, ship.location, w, ship.fuel_capacity)
     pprint(p)
+  
+  def do_list(self, klass):
+    ship = self.has_ship()
+    for o in self.store.all_members(klass, ship.location.system):
+      print(o)
+    
diff --git a/nullptr/general.py b/nullptr/general.py
index e1b9709..4ad4f39 100644
--- a/nullptr/general.py
+++ b/nullptr/general.py
@@ -46,8 +46,11 @@ class General:
     ag = self.agent.symbol
     command = self.store.get('Ship', f'{ag}-1')
     probe = self.store.get('Ship', f'{ag}-2')
-    command.role = 'probe'
-    probe.role = 'sitter'
+    if command.role is None:
+      command.role = 'probe'
+    if probe.role is None:
+      probe.role = 'sitter'
+    
     
   def phase_probes(self):
     # * probes on all markets
diff --git a/nullptr/missions/base.py b/nullptr/missions/base.py
index 51f8aed..5bb4313 100644
--- a/nullptr/missions/base.py
+++ b/nullptr/missions/base.py
@@ -322,7 +322,8 @@ class BaseMission(Mission):
     if self.ship.fuel_capacity == 0:
       steps = {
       
-      f'travel-{nm}': (calc, f'go-{nm}'),
+      f'travel-{nm}': (calc, f'orbit-{nm}'),
+      f'orbit-{nm}': (self.step_orbit, f'go-{nm}'),
       f'go-{nm}': (self.step_travel, f'nav-{nm}'),
       f'nav-{nm}': (self.step_navigate_traject, {
         'done': next_step,
diff --git a/nullptr/missions/trade.py b/nullptr/missions/trade.py
index 3310bd2..8655b45 100644
--- a/nullptr/missions/trade.py
+++ b/nullptr/missions/trade.py
@@ -13,7 +13,7 @@ class TradeMission(BaseMission):
     cargo_space = self.ship.cargo_capacity - self.ship.cargo_units
     smkt = self.store.get('Marketplace', self.st('site'))
     dmkt = self.store.get('Marketplace', self.st('dest'))
-    resource = find_deal(smkt, dmkt)
+    resource = find_deal(self.c, smkt, dmkt)
     if resource is None:
       return 'done'
     price = smkt.buy_price(resource)
diff --git a/nullptr/roles/__init__.py b/nullptr/roles/__init__.py
index 6a8a709..1dcd54c 100644
--- a/nullptr/roles/__init__.py
+++ b/nullptr/roles/__init__.py
@@ -4,6 +4,7 @@ from nullptr.roles.siphon import assign_siphon
 from nullptr.roles.hauler import assign_hauler
 from nullptr.roles.surveyor import assign_surveyor
 from nullptr.roles.miner import assign_miner
+from nullptr.roles.sitter import assign_sitter
 
 def assign_mission(c, s):
   if s.role == 'trader':
@@ -18,3 +19,5 @@ def assign_mission(c, s):
     assign_surveyor(c, s)
   elif s.role == 'miner':
     assign_miner(c, s)
+  elif s.role == 'sitter':
+    assign_sitter(c, s)
diff --git a/nullptr/roles/sitter.py b/nullptr/roles/sitter.py
new file mode 100644
index 0000000..aa37b4b
--- /dev/null
+++ b/nullptr/roles/sitter.py
@@ -0,0 +1,26 @@
+from nullptr.analyzer import Point
+
+def assign_sitter_at(c, s, w):
+  c.captain.init_mission(s, 'sit')
+  c.captain.smipa(s, 'dest', w.symbol)
+
+def assign_sitter(c, s):
+  system = s.location.system
+  ships = c.store.all('Ship')
+  markets = c.store.all_members(system, 'Marketplace')
+  origin = Point(0, 0)
+  markets = sorted(markets, key=lambda m: m.waypoint.distance(origin))
+  shipyards = c.store.all_members(system, 'Shipyard')
+  occupied = [s.mission_state['dest'] for s in ships if s.mission=='sit']
+  probe_shipyard = [y for y in shipyards if 'SHIP_PROBE' in y.types][0]
+  print('oc', occupied)
+  print('proya', probe_shipyard)
+  
+  if probe_shipyard.symbol not in occupied:
+    return assign_sitter_at(c, s, probe_shipyard)
+  for y in shipyards:
+    if y.symbol not in occupied:
+      return assign_sitter_at(c, s, y)
+  for m in markets:
+    if m.symbol not in occupied:
+      return assign_sitter_at(c, s, m)
\ No newline at end of file
diff --git a/nullptr/store.py b/nullptr/store.py
index cfd9afb..07b4fba 100644
--- a/nullptr/store.py
+++ b/nullptr/store.py
@@ -227,7 +227,7 @@ class Store:
     symbol = obj.symbol
     obj.store = self
     self.data[typ][symbol] = obj
-    if type(obj).__name__ in ['Waypoint','Marketplace', 'Jumpgate', 'Survey']:
+    if type(obj).__name__ in ['Waypoint','Marketplace', 'Jumpgate', 'Survey', 'Shipyard']:
       system_str = obj.system.symbol
       if system_str not in self.system_members:
         self.system_members[system_str] = set()