diff --git a/README.md b/README.md
index 18e8ba4..5c159ab 100644
--- a/README.md
+++ b/README.md
@@ -63,10 +63,8 @@ Create a new database and user, for example:
 ```
 $ sudo -iu postgres
 $ psql
-# CREATE DATABASE "hanab-live";
-# \c hanab-live
 # CREATE USER hanabi WITH PASSWORD 'Insert password here';
-# ALTER DATABASE "hanab-live" OWNER TO hanabi;
+# CREATE DATABASE "hanab-live" with owner "hanabi";
 ```
 Put the connection parameters in a config file (for the format, see `example_config.yaml`).
 This should be located at your system default for the application `hanabi-suite`,
diff --git a/hanabi/hanab_game.py b/hanabi/hanab_game.py
index 08d00f8..0783f21 100644
--- a/hanabi/hanab_game.py
+++ b/hanabi/hanab_game.py
@@ -287,6 +287,12 @@ class GameState:
 
     # Utilities
 
+    def is_playable(self, card: DeckCard):
+        return self.stacks[card.suitIndex] + 1 == card.rank
+
+    def is_trash(self, card: DeckCard):
+        return self.stacks[card.suitIndex] >= card.rank
+
     def holding_players(self, card):
         for (player, hand) in enumerate(self.hands):
             if card in hand:
diff --git a/requirements.txt b/requirements.txt
index cf70c11..af32b12 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,3 +10,4 @@ verboselogs
 pebble
 platformdirs
 PyYAML
+cython==0.29.36