diff --git a/src/Stylist.hs b/src/Stylist.hs
--- a/src/Stylist.hs
+++ b/src/Stylist.hs
@@ -27,6 +27,9 @@
     inherit :: a -> a
     inherit = id
 
+    priority :: a -> [Text]
+    priority _ = []
+
     -- | Expand a shorthand property into longhand properties.
     shorthand :: a -> Text -> [Token] -> [(Text, [Token])]
     shorthand self key value | Just _ <- longhand self self key value = [(key, value)]
diff --git a/stylist-traits.cabal b/stylist-traits.cabal
--- a/stylist-traits.cabal
+++ b/stylist-traits.cabal
@@ -10,7 +10,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.1.2.0
+version:             0.1.3.0
 
 -- A short (one-line) description of the package.
 synopsis:            Traits, datatypes, & parsers for Haskell Stylist