diff --git a/CHANGES.md b/CHANGES.md
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -7,6 +7,10 @@
 # Unreleased
 
 
+# 0.9.2
+
+* Bump upper bound on `base` to <4.19.
+
 # 0.9.1
 
 * Bump upper bound on `base` to <4.17.
diff --git a/nyan-interpolation-core.cabal b/nyan-interpolation-core.cabal
--- a/nyan-interpolation-core.cabal
+++ b/nyan-interpolation-core.cabal
@@ -1,13 +1,11 @@
 cabal-version: 2.0
 
--- This file has been generated from package.yaml by hpack version 0.35.0.
+-- This file has been generated from package.yaml by hpack version 0.35.1.
 --
 -- see: https://github.com/sol/hpack
---
--- hash: 454835beb066a76fcd19ff1540bc89d3e2f2732ac9d7164ec5903d0eb782bebd
 
 name:           nyan-interpolation-core
-version:        0.9.1
+version:        0.9.2
 synopsis:       Customize your nyan interpolator!
 description:    This package to tune up your own variation of interpolator. Declare new rendering modes, set desired switches defaults and more.
 category:       Interpolation, Text
@@ -66,6 +64,7 @@
       RecordWildCards
       ScopedTypeVariables
       StandaloneDeriving
+      StandaloneKindSignatures
       TemplateHaskell
       TupleSections
       TypeFamilies
@@ -74,9 +73,9 @@
       TypeApplications
       TypeOperators
       QuasiQuotes
-  ghc-options: -Weverything -Wno-missing-export-lists -Wno-missing-exported-signatures -Wno-missing-import-lists -Wno-missed-specialisations -Wno-all-missed-specialisations -Wno-unsafe -Wno-safe -Wno-missing-local-signatures -Wno-monomorphism-restriction -Wno-implicit-prelude -Wno-prepositive-qualified-module -Wno-missing-safe-haskell-mode -Wno-unused-packages
+  ghc-options: -Weverything -Wno-missing-export-lists -Wno-missing-exported-signatures -Wno-missing-import-lists -Wno-missing-kind-signatures -Wno-missed-specialisations -Wno-all-missed-specialisations -Wno-unsafe -Wno-safe -Wno-missing-local-signatures -Wno-monomorphism-restriction -Wno-implicit-prelude -Wno-prepositive-qualified-module -Wno-missing-safe-haskell-mode -Wno-unused-packages
   build-depends:
-      base <4.17
+      base <4.19
     , fmt
     , megaparsec
     , mtl
@@ -124,6 +123,7 @@
       RecordWildCards
       ScopedTypeVariables
       StandaloneDeriving
+      StandaloneKindSignatures
       TemplateHaskell
       TupleSections
       TypeFamilies
@@ -132,12 +132,12 @@
       TypeApplications
       TypeOperators
       QuasiQuotes
-  ghc-options: -Weverything -Wno-missing-export-lists -Wno-missing-exported-signatures -Wno-missing-import-lists -Wno-missed-specialisations -Wno-all-missed-specialisations -Wno-unsafe -Wno-safe -Wno-missing-local-signatures -Wno-monomorphism-restriction -Wno-implicit-prelude -Wno-prepositive-qualified-module -Wno-missing-safe-haskell-mode -Wno-unused-packages
+  ghc-options: -Weverything -Wno-missing-export-lists -Wno-missing-exported-signatures -Wno-missing-import-lists -Wno-missing-kind-signatures -Wno-missed-specialisations -Wno-all-missed-specialisations -Wno-unsafe -Wno-safe -Wno-missing-local-signatures -Wno-monomorphism-restriction -Wno-implicit-prelude -Wno-prepositive-qualified-module -Wno-missing-safe-haskell-mode -Wno-unused-packages
   build-tool-depends:
       tasty-discover:tasty-discover
   build-depends:
       HUnit
-    , base <4.17
+    , base <4.19
     , fmt
     , megaparsec
     , mtl
diff --git a/src/Text/Interpolation/Nyan/Core/Internal/RMode.hs b/src/Text/Interpolation/Nyan/Core/Internal/RMode.hs
--- a/src/Text/Interpolation/Nyan/Core/Internal/RMode.hs
+++ b/src/Text/Interpolation/Nyan/Core/Internal/RMode.hs
@@ -6,6 +6,7 @@
   ( RMode(..)
   ) where
 
+import Data.Kind (Type)
 import Fmt (Builder)
 
 {- | Type that describes rendering modes.
@@ -30,4 +31,5 @@
 "Value is 0x20"
 
 -}
+type RMode :: Type -> Type
 newtype RMode a = RMode { renderWithMode :: a -> Builder }
diff --git a/tests/Test/Util.hs b/tests/Test/Util.hs
--- a/tests/Test/Util.hs
+++ b/tests/Test/Util.hs
@@ -91,6 +91,9 @@
   qAddCorePlugin a = liftToTestQ $ qAddCorePlugin a
   qGetQ = liftToTestQ qGetQ
   qPutQ a = liftToTestQ $ qPutQ a
+  qGetDoc a = liftToTestQ $ qGetDoc a
+  qPutDoc a b = liftToTestQ $ qPutDoc a b
+  qGetPackageRoot = liftToTestQ $ qGetPackageRoot
 
 -- * Interpolators