diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Revision history for large-anon
 
+## 0.3.4 -- 2026-05-20
+
+* Support ghc 9.14
+* Use ghc-tcplugin-api 0.19
+
 ## 0.3.3 -- 2025-07-19
 
 * Support ghc 9.8 (Gabriele Sales)
diff --git a/large-anon.cabal b/large-anon.cabal
--- a/large-anon.cabal
+++ b/large-anon.cabal
@@ -1,6 +1,6 @@
 cabal-version:      2.4
 name:               large-anon
-version:            0.3.3
+version:            0.3.4
 synopsis:           Scalable anonymous records
 description:        The @large-anon@ package provides support for anonymous
                     records in Haskell, with a focus on compile-time (and
@@ -13,12 +13,14 @@
 extra-doc-files:    CHANGELOG.md
                     test/Test/Sanity/RebindableSyntax/Tests.hs
 tested-with:        GHC ==8.10.7
+                    GHC ==9.0.2
                     GHC ==9.2.8
                     GHC ==9.4.8
                     GHC ==9.6.7
                     GHC ==9.8.4
                     GHC ==9.10.2
                     GHC ==9.12.2
+                    GHC ==9.14.1
 
 library
   exposed-modules:
@@ -76,11 +78,11 @@
 
   build-depends:
     , aeson            >= 1.4.4  && < 2.3
-    , base             >= 4.14   && < 4.22
+    , base             >= 4.14   && < 4.23
     , containers       >= 0.6.2  && < 0.9
     , deepseq          >= 1.4.4  && < 1.6
-    , ghc              >= 8.10   && < 9.13
-    , ghc-tcplugin-api >= 0.16.1 && < 0.17
+    , ghc              >= 8.10   && < 9.15
+    , ghc-tcplugin-api >= 0.19   && < 0.20
     , hashable         >= 1.3    && < 1.6
     , mtl              >= 2.2.1  && < 2.4
     , optics-core      >= 0.3    && < 0.5
@@ -109,6 +111,10 @@
     cpp-options:
       -DDEBUG
 
+  if flag(enable-core-lint)
+    ghc-options:
+      -dcore-lint
+
 test-suite test-large-anon
   default-language:
       Haskell2010
@@ -192,7 +198,16 @@
     cpp-options:
       -DNO_RECORD_DOT_PREPROCESSOR
 
+  if flag(enable-core-lint)
+    ghc-options:
+      -dcore-lint
+
 Flag debug
   Description: Enable internal debugging features
+  Default: False
+  Manual: True
+
+Flag enable-core-lint
+  Description: Debugging: Enable GHC's core linter
   Default: False
   Manual: True
diff --git a/src/Data/Record/Anon.hs b/src/Data/Record/Anon.hs
--- a/src/Data/Record/Anon.hs
+++ b/src/Data/Record/Anon.hs
@@ -72,7 +72,3 @@
 import Data.Record.Anon.Internal.Advanced (Field, Some(..))
 import Data.Record.Anon.Internal.Reflection (Reflected(Reflected))
 
-
-
-
-
diff --git a/src/Data/Record/Anon/Advanced.hs b/src/Data/Record/Anon/Advanced.hs
--- a/src/Data/Record/Anon/Advanced.hs
+++ b/src/Data/Record/Anon/Advanced.hs
@@ -583,4 +583,3 @@
 castEqual :: Equal a b => a -> b
 castEqual = TypeLet.castEqual
 
-
diff --git a/src/Data/Record/Anon/Internal/Advanced.hs b/src/Data/Record/Anon/Internal/Advanced.hs
--- a/src/Data/Record/Anon/Internal/Advanced.hs
+++ b/src/Data/Record/Anon/Internal/Advanced.hs
@@ -677,4 +677,3 @@
   -> Record f r
 letInsertAs _ n x r = letAs' (insert n x r)
 
-
diff --git a/src/Data/Record/Anon/Internal/Core/Canonical.hs b/src/Data/Record/Anon/Internal/Core/Canonical.hs
--- a/src/Data/Record/Anon/Internal/Core/Canonical.hs
+++ b/src/Data/Record/Anon/Internal/Core/Canonical.hs
diff --git a/src/Data/Record/Anon/Internal/Core/FieldName.hs b/src/Data/Record/Anon/Internal/Core/FieldName.hs
--- a/src/Data/Record/Anon/Internal/Core/FieldName.hs
+++ b/src/Data/Record/Anon/Internal/Core/FieldName.hs
@@ -65,4 +65,3 @@
 instance Outputable FieldName where
   ppr = pprString . fieldNameLabel
 
-
diff --git a/src/Data/Record/Anon/Internal/Plugin.hs b/src/Data/Record/Anon/Internal/Plugin.hs
--- a/src/Data/Record/Anon/Internal/Plugin.hs
+++ b/src/Data/Record/Anon/Internal/Plugin.hs
@@ -40,6 +40,7 @@
       tcPluginInit    = nameResolution
     , tcPluginSolve   = solve
     , tcPluginRewrite = rewrite
-    , tcPluginStop    = const $ return ()
+    , tcPluginPostTc   = const $ return ()
+    , tcPluginShutdown = const $ return ()
     }
 
diff --git a/src/Data/Record/Anon/Internal/Plugin/Source/GhcShim.hs b/src/Data/Record/Anon/Internal/Plugin/Source/GhcShim.hs
--- a/src/Data/Record/Anon/Internal/Plugin/Source/GhcShim.hs
+++ b/src/Data/Record/Anon/Internal/Plugin/Source/GhcShim.hs
@@ -257,6 +257,9 @@
 #if __GLASGOW_HASKELL__ >= 906
     , ideclImportList = Nothing
 #endif
+#if __GLASGOW_HASKELL__ >= 914
+    , ideclLevelSpec = NotLevelled
+#endif
     }
 
 issueWarning :: SrcSpan -> SDoc -> Hsc ()
@@ -294,7 +297,11 @@
                          (initPrintConfig dynFlags)
                          (initDiagOpts dynFlags)
 
+#if __GLASGOW_HASKELL__ >= 914
+    let msg :: Err.UnknownDiagnostic opts Err.GhcHint
+#else
     let msg :: Err.UnknownDiagnostic opts
+#endif
         msg = Err.mkSimpleUnknownDiagnostic $
                 mkPlainError [] errMsg
 #endif
diff --git a/src/Data/Record/Anon/Internal/Plugin/TC/Constraints/KnownHash.hs b/src/Data/Record/Anon/Internal/Plugin/TC/Constraints/KnownHash.hs
--- a/src/Data/Record/Anon/Internal/Plugin/TC/Constraints/KnownHash.hs
+++ b/src/Data/Record/Anon/Internal/Plugin/TC/Constraints/KnownHash.hs
@@ -48,7 +48,7 @@
   -> Ct
   -> ParseResult Void (GenLocated CtLoc CKnownHash)
 parseKnownHash _ ResolvedNames{..} =
-    parseConstraint isRelevant $ \(ty, label) -> do
+    parseConstraint isRelevant (text "isRelevant") $ \(ty, label) -> do
       return $ CKnownHash {
           knownHashLabel = label
         , knownHashType  = ty
diff --git a/src/Data/Record/Anon/Internal/Plugin/TC/EquivClasses.hs b/src/Data/Record/Anon/Internal/Plugin/TC/EquivClasses.hs
--- a/src/Data/Record/Anon/Internal/Plugin/TC/EquivClasses.hs
+++ b/src/Data/Record/Anon/Internal/Plugin/TC/EquivClasses.hs
diff --git a/src/Data/Record/Anon/Internal/Plugin/TC/Parsing.hs b/src/Data/Record/Anon/Internal/Plugin/TC/Parsing.hs
--- a/src/Data/Record/Anon/Internal/Plugin/TC/Parsing.hs
+++ b/src/Data/Record/Anon/Internal/Plugin/TC/Parsing.hs
@@ -81,10 +81,11 @@
 parseConstraint ::
      HasCallStack
   => (Class -> [Type] -> Maybe a) -- ^ Do we want to try and match against this?
+  -> SDoc                         -- ^ Description of above predicate
   -> (a -> Maybe b)               -- ^ Parser for the class arguments
   -> Ct                           -- ^ Constraint to parse
   -> ParseResult e (GenLocated CtLoc b)
-parseConstraint p f ct = fmap (L $ ctLoc ct) $
+parseConstraint p doc f ct = fmap (L $ ctLoc ct) $
     -- TODO: classify up to equalities..?
     case classifyPredType (ctPred ct) of
       ClassPred cls args | Just a <- p cls args ->
@@ -97,6 +98,8 @@
               , showSDocUnsafe (ppr cls)
               , " constraint with arguments:\n"
               , unlines (map (showSDocUnsafe . ppr) args)
+              , "\nWhen parsing " ++ showSDocUnsafe (ppr ct)
+              , "\nlooking for " ++ showSDocUnsafe doc
               , "\nat\n"
               , prettyCallStack callStack
               ]
@@ -110,7 +113,7 @@
   -> ([Type] -> Maybe a)          -- ^ Parser for the class arguments
   -> Ct                           -- ^ Constraint to parse
   -> ParseResult e (GenLocated CtLoc a)
-parseConstraint' cls = parseConstraint p
+parseConstraint' cls = parseConstraint p (ppr cls)
   where
     p :: Class -> [Type] -> Maybe [Type]
     p cls' args = if cls == cls' then Just args else Nothing
@@ -152,4 +155,11 @@
     -- When this is the case, however, by injectivity of 'tyCon' we know that
     -- @args1 ~ args1'@, so we can just return /any/ of the matches; we will
     -- return the first.
-    lookup tyCon (toList splits)
+    --
+    -- 2025-08-26: we ignore constraints here.
+    -- Prior using ghc-tcplugin-api-0.17 we ignored them by necessity and plugin worked.
+    -- There is a concern that the plugin should record (equality) constraints
+    -- used for reasoning in evidences it constructs,
+    -- but AFAIK, GHC simply has no direct mechanism to do that
+    -- (see the hoops GHC itself jumps though to make `unsafeCoerce` behave well).
+    lookup tyCon [ (x,y) | (x,y,_) <- toList splits]
diff --git a/src/Data/Record/Anon/Internal/Plugin/TC/Row/ParsedRow.hs b/src/Data/Record/Anon/Internal/Plugin/TC/Row/ParsedRow.hs
--- a/src/Data/Record/Anon/Internal/Plugin/TC/Row/ParsedRow.hs
+++ b/src/Data/Record/Anon/Internal/Plugin/TC/Row/ParsedRow.hs
@@ -115,7 +115,7 @@
         , do FieldsVar <$> getTyVar_maybe fields
         , do args <- parseInjTyConApp tcs tyConMerge fields
              (left, right) <- case args of
-                                [l, r]     -> return (l, r)
+                                [_k, l, r]     -> return (l, r)
                                 _otherwise -> mzero
              FieldsMerge <$> go left <*> go right
         ]
diff --git a/src/Data/Record/Anon/Internal/Util/StrictArray.hs b/src/Data/Record/Anon/Internal/Util/StrictArray.hs
--- a/src/Data/Record/Anon/Internal/Util/StrictArray.hs
+++ b/src/Data/Record/Anon/Internal/Util/StrictArray.hs
diff --git a/src/Data/Record/Anon/Overloading.hs b/src/Data/Record/Anon/Overloading.hs
--- a/src/Data/Record/Anon/Overloading.hs
+++ b/src/Data/Record/Anon/Overloading.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP                 #-}
 {-# LANGUAGE PolyKinds           #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TypeApplications    #-}
@@ -41,5 +42,11 @@
 ifThenElse :: Bool -> a -> a -> a
 ifThenElse b x y = if b then x else y
 
+-- | NOTE: the order of arguments is GHC version dependent.
+#if __GLASGOW_HASKELL__ >=914
+setField :: forall x r a. GHC.Records.Compat.HasField x r a => a -> r -> r
+setField = flip (fst . GHC.Records.Compat.hasField @x)
+#else
 setField :: forall x r a. GHC.Records.Compat.HasField x r a => r -> a -> r
 setField = fst . GHC.Records.Compat.hasField @x
+#endif
diff --git a/src/Data/Record/Anon/Plugin.hs b/src/Data/Record/Anon/Plugin.hs
--- a/src/Data/Record/Anon/Plugin.hs
+++ b/src/Data/Record/Anon/Plugin.hs
@@ -1,15 +1,6 @@
 {-# OPTIONS_HADDOCK hide #-}
 
--- | Type checker and source plugin for working with anonymous records
---
--- To use this, add
---
--- > {-# OPTIONS_GHC -fplugin=Data.Record.Anon.Plugin #-}
---
--- to your module. You should not need to import this module; see
--- "Data.Record.Anon.Simple" or "Data.Record.Anon.Advanced" instead.
 module Data.Record.Anon.Plugin (plugin) where
 
 import Data.Record.Anon.Internal.Plugin (plugin)
-
 
diff --git a/test/Test/Infra/Discovery.hs b/test/Test/Infra/Discovery.hs
--- a/test/Test/Infra/Discovery.hs
+++ b/test/Test/Infra/Discovery.hs
@@ -210,4 +210,3 @@
 pairSnd :: Product f g x -> g x
 pairSnd (Pair _ gx) = gx
 
-
diff --git a/test/Test/Infra/Generics.hs b/test/Test/Infra/Generics.hs
--- a/test/Test/Infra/Generics.hs
+++ b/test/Test/Infra/Generics.hs
@@ -68,5 +68,3 @@
     name :: forall n a. KnownSymbol n => K String '(n, a)
     name = K (symbolVal (Proxy @n))
 
-
-
diff --git a/test/Test/Prop/Record/Model/Orphans.hs b/test/Test/Prop/Record/Model/Orphans.hs
--- a/test/Test/Prop/Record/Model/Orphans.hs
+++ b/test/Test/Prop/Record/Model/Orphans.hs
diff --git a/test/Test/Sanity/BlogPost.hs b/test/Test/Sanity/BlogPost.hs
--- a/test/Test/Sanity/BlogPost.hs
+++ b/test/Test/Sanity/BlogPost.hs
diff --git a/test/Test/Sanity/Generics.hs b/test/Test/Sanity/Generics.hs
--- a/test/Test/Sanity/Generics.hs
+++ b/test/Test/Sanity/Generics.hs
diff --git a/test/Test/Sanity/HasField.hs b/test/Test/Sanity/HasField.hs
--- a/test/Test/Sanity/HasField.hs
+++ b/test/Test/Sanity/HasField.hs
@@ -60,4 +60,3 @@
 
     assertEqual "set field 1" record1' $ Anon.set #x (I False) record1
 
-
diff --git a/test/Test/Sanity/Intersection.hs b/test/Test/Sanity/Intersection.hs
--- a/test/Test/Sanity/Intersection.hs
+++ b/test/Test/Sanity/Intersection.hs
diff --git a/test/Test/Sanity/OverloadedRecordDot.hs b/test/Test/Sanity/OverloadedRecordDot.hs
--- a/test/Test/Sanity/OverloadedRecordDot.hs
+++ b/test/Test/Sanity/OverloadedRecordDot.hs
diff --git a/test/Test/Sanity/OverloadedRecordUpdate.hs b/test/Test/Sanity/OverloadedRecordUpdate.hs
--- a/test/Test/Sanity/OverloadedRecordUpdate.hs
+++ b/test/Test/Sanity/OverloadedRecordUpdate.hs
diff --git a/test/Test/Sanity/RebindableSyntax/Disabled.hs b/test/Test/Sanity/RebindableSyntax/Disabled.hs
--- a/test/Test/Sanity/RebindableSyntax/Disabled.hs
+++ b/test/Test/Sanity/RebindableSyntax/Disabled.hs
diff --git a/test/Test/Sanity/RebindableSyntax/Tests.hs b/test/Test/Sanity/RebindableSyntax/Tests.hs
--- a/test/Test/Sanity/RebindableSyntax/Tests.hs
+++ b/test/Test/Sanity/RebindableSyntax/Tests.hs
diff --git a/test/Test/Sanity/Simple.hs b/test/Test/Sanity/Simple.hs
--- a/test/Test/Sanity/Simple.hs
+++ b/test/Test/Sanity/Simple.hs
diff --git a/test/TestLargeAnon.hs b/test/TestLargeAnon.hs
--- a/test/TestLargeAnon.hs
+++ b/test/TestLargeAnon.hs