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diff --git a/users/aspen/xanthous/src/Xanthous/App/Autocommands.hs b/users/aspen/xanthous/src/Xanthous/App/Autocommands.hs
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+--------------------------------------------------------------------------------
+module Xanthous.App.Autocommands
+  ( runAutocommand
+  , autoStep
+  ) where
+--------------------------------------------------------------------------------
+import           Xanthous.Prelude
+--------------------------------------------------------------------------------
+import           Control.Concurrent (threadDelay)
+import qualified Data.Aeson as A
+import           Data.Aeson (object)
+import           Data.List.NonEmpty (nonEmpty)
+import qualified Data.List.NonEmpty as NE
+import           Control.Monad.State (gets)
+--------------------------------------------------------------------------------
+import           Xanthous.App.Common
+import           Xanthous.App.Time
+import           Xanthous.Data
+import           Xanthous.Data.App
+import           Xanthous.Entities.Character (speed, isFullyHealed)
+import           Xanthous.Entities.Creature (Creature, creatureType)
+import           Xanthous.Entities.RawTypes (hostile)
+import           Xanthous.Game.State
+--------------------------------------------------------------------------------
+
+-- | Step the given autocommand forward once
+autoStep :: Autocommand -> AppM ()
+autoStep (AutoMove dir) = do
+  newPos <- uses characterPosition $ move dir
+  collisionAt newPos >>= \case
+    Nothing -> do
+      characterPosition .= newPos
+      stepGameBy =<< uses (character . speed) (|*| (1 :: Tiles))
+      describeEntitiesAt newPos
+      cancelIfDanger
+    Just _ -> cancelAutocommand
+
+autoStep AutoRest = do
+  done <- uses character isFullyHealed
+  if done
+    then say_ ["autocommands", "doneResting"] >> cancelAutocommand
+    else stepGame >> cancelIfDanger
+
+-- | Cancel the autocommand if the character is in danger
+cancelIfDanger :: AppM ()
+cancelIfDanger = do
+  maybeVisibleEnemies <- nonEmpty <$> enemiesInSight
+  for_ maybeVisibleEnemies $ \visibleEnemies -> do
+    say ["autocommands", "enemyInSight"]
+      $ object [ "firstEntity" A..= NE.head visibleEnemies ]
+    cancelAutocommand
+  where
+    enemiesInSight :: AppM [Creature]
+    enemiesInSight = do
+      ents <- gets characterVisibleEntities
+      pure $ ents
+          ^.. folded
+            . _SomeEntity @Creature
+            . filtered (view $ creatureType . hostile)
+
+--------------------------------------------------------------------------------
+
+autocommandIntervalμs :: Int
+autocommandIntervalμs = 1000 * 50 -- 50 ms
+
+runAutocommand :: Autocommand -> AppM ()
+runAutocommand ac = do
+  env <- ask
+  tid <- liftIO . async $ runReaderT go env
+  autocommand .= ActiveAutocommand ac tid
+  where
+    go = everyμs autocommandIntervalμs $ sendEvent AutoContinue
+
+-- | Perform 'act' every μs microseconds forever
+everyμs :: MonadIO m => Int -> m () -> m ()
+everyμs μs act = act >> liftIO (threadDelay μs) >> everyμs μs act