diff --git a/polysemy-plugin.cabal b/polysemy-plugin.cabal
--- a/polysemy-plugin.cabal
+++ b/polysemy-plugin.cabal
@@ -1,11 +1,11 @@
 cabal-version: 2.0
 
--- This file has been generated from package.yaml by hpack version 0.36.1.
+-- This file has been generated from package.yaml by hpack version 0.38.3.
 --
 -- see: https://github.com/sol/hpack
 
 name:           polysemy-plugin
-version:        0.4.5.3
+version:        0.4.6.0
 synopsis:       Disambiguate obvious uses of effects.
 description:    Please see the README on GitHub at <https://github.com/polysemy-research/polysemy/tree/master/polysemy-plugin#readme>
 category:       Polysemy
@@ -27,7 +27,7 @@
 
 custom-setup
   setup-depends:
-      Cabal <3.13
+      Cabal <3.15
     , base >=4.9 && <5
     , cabal-doctest >=1.0.6 && <1.1
 
@@ -65,13 +65,15 @@
       UnicodeSyntax
   build-depends:
       base >=4.9 && <5
-    , containers >=0.5 && <0.8
+    , containers >=0.5 && <0.9
     , ghc >=8.6.5 && <10
-    , ghc-tcplugins-extra >=0.3 && <0.6
     , polysemy >=1.7
     , syb ==0.7.*
     , transformers >=0.5.2.0 && <0.7
   default-language: Haskell2010
+  if impl(ghc < 9.14)
+    build-depends:
+        ghc-tcplugins-extra >=0.3 && <0.6
 
 test-suite polysemy-plugin-test
   type: exitcode-stdio-1.0
@@ -110,10 +112,9 @@
   ghc-options: -threaded -rtsopts -with-rtsopts=-N -fplugin=Polysemy.Plugin
   build-depends:
       base >=4.9 && <5
-    , containers >=0.5 && <0.8
-    , doctest >=0.16.0.1 && <0.25
+    , containers >=0.5 && <0.9
+    , doctest >=0.16.0.1 && <0.26
     , ghc >=8.6.5 && <10
-    , ghc-tcplugins-extra >=0.3 && <0.6
     , hspec >=2.6.0 && <3
     , hspec-discover
     , inspection-testing >=0.4.2 && <0.7
diff --git a/src/Polysemy/Plugin/Fundep.hs b/src/Polysemy/Plugin/Fundep.hs
--- a/src/Polysemy/Plugin/Fundep.hs
+++ b/src/Polysemy/Plugin/Fundep.hs
@@ -100,6 +100,10 @@
 import           TysPrim (alphaTys)
 #endif
 
+#if __GLASGOW_HASKELL__ >= 914
+import           GHC.Core.Predicate (tyCoVarsOfTypeWellScoped)
+#endif
+
 fundepPlugin :: TcPlugin
 fundepPlugin = TcPlugin
   { tcPluginInit =
@@ -249,7 +253,11 @@
            $ newWantedEq (fcLoc fc) Nominal wanted given
 #endif
   pure ( Unification (OrdType wanted) (OrdType given)
+#if __GLASGOW_HASKELL__ >= 914
+       , CNonCanonical (CtWanted ev)
+#else
        , CNonCanonical ev
+#endif
        )
   where
     wanted = fcEffect fc
diff --git a/src/Polysemy/Plugin/Fundep/Stuff.hs b/src/Polysemy/Plugin/Fundep/Stuff.hs
--- a/src/Polysemy/Plugin/Fundep/Stuff.hs
+++ b/src/Polysemy/Plugin/Fundep/Stuff.hs
@@ -8,7 +8,6 @@
 
 import Data.Kind (Type)
 import GHC (Name, Class, TyCon, mkModuleName)
-import GHC.TcPluginM.Extra (lookupModule, lookupName)
 #if __GLASGOW_HASKELL__ >= 900
 import GHC.Data.FastString (fsLit)
 import GHC.Types.Name.Occurrence (mkTcOcc)
@@ -36,6 +35,39 @@
 import Outputable (pprPanic, text, (<+>), ($$))
 #endif
 
+#if __GLASGOW_HASKELL__ >= 914
+import GHC (Module, ModuleName)
+import GHC.Data.FastString (FastString)
+import GHC.Driver.Env (hsc_home_unit_maybe)
+import GHC.Tc.Plugin (findImportedModule, lookupOrig, tcPluginIO)
+import GHC.Types.Name (OccName)
+import GHC.Types.PkgQual (PkgQual (ThisPkg))
+import GHC.Unit.Finder (FindResult (Found), findPluginModule)
+import GHC.Unit.Home (homeUnitId)
+import GHC.Utils.Outputable (ppr)
+import GHC.Utils.Panic (panicDoc)
+#else
+import GHC.TcPluginM.Extra (lookupModule, lookupName)
+#endif
+
+#if __GLASGOW_HASKELL__ >= 914
+
+-- | Port of @lookupModule@ from the abandoned @ghc-tcplugins-extra@.
+lookupModule :: ModuleName -> FastString -> TcPluginM Module
+lookupModule mod_nm _pkg = do
+  hsc_env <- getTopEnv
+  tcPluginIO (findPluginModule hsc_env mod_nm) >>= \case
+    Found _ m -> pure m
+    _ -> do
+      let pkg_qual = maybe NoPkgQual (ThisPkg . homeUnitId) (hsc_home_unit_maybe hsc_env)
+      findImportedModule mod_nm pkg_qual >>= \case
+        Found _ m -> pure m
+        _ -> panicDoc "Couldn't find module" (ppr mod_nm)
+
+lookupName :: Module -> OccName -> TcPluginM Name
+lookupName = lookupOrig
+
+#endif
 
 
 ------------------------------------------------------------------------------
diff --git a/src/Polysemy/Plugin/Fundep/Unification.hs b/src/Polysemy/Plugin/Fundep/Unification.hs
--- a/src/Polysemy/Plugin/Fundep/Unification.hs
+++ b/src/Polysemy/Plugin/Fundep/Unification.hs
@@ -81,22 +81,41 @@
         InterpreterUse _ s -> s
         FunctionDef s      -> s
 
+#if __GLASGOW_HASKELL__ < 914
+
 #if __GLASGOW_HASKELL__ >= 902
+
 #define BINDME (const BindMe)
 #define APART (const Apart)
+
 #else
+
 #define BINDME BindMe
 #define APART Skolem
+
 #endif
 
+#endif
+
 tryUnifyUnivarsButNotSkolems :: Set TyVar -> Type -> Type -> Maybe SUBST
 tryUnifyUnivarsButNotSkolems skolems goal inst =
+#if __GLASGOW_HASKELL__ >= 914
+  -- the tyfam case only distinguishes MaybeApart from SurelyApart anyway, so it doesn't matter what we do..
   case tcUnifyTysFG
+         alwaysBindFam
+         (\ tv _ -> bool BindMe DontBindMe (S.member tv skolems))
+         [inst]
+         [goal] of
+    Unifiable subst -> pure subst
+    _               -> Nothing
+#else
+  case tcUnifyTysFG
          (bool BINDME APART . flip S.member skolems)
          [inst]
          [goal] of
     Unifiable subst -> pure subst
     _               -> Nothing
+#endif
 
 ------------------------------------------------------------------------------
 -- | A wrapper for two types that we want to say have been unified.