diff --git a/ParamTree.hs b/ParamTree.hs
--- a/ParamTree.hs
+++ b/ParamTree.hs
@@ -8,7 +8,7 @@
 -------------------------------------------------------------------------------
 -- |
 -- Module      :  ParamTree
--- Copyright   :  (C) 2017 Merijn Verstraaten
+-- Copyright   :  (C) 2017-2023 Merijn Verstraaten
 -- License     :  BSD-style (see the file LICENSE)
 -- Maintainer  :  Merijn Verstraaten <merijn@inconsistent.nl>
 -- Stability   :  experimental
@@ -29,29 +29,21 @@
     , paramSets
     ) where
 
+import Data.Kind (Type)
 import Data.Map (Map)
 import qualified Data.Map as M
-#if !MIN_VERSION_base(4,8,0)
-import Data.Monoid (mconcat)
-#endif
 import Data.Monoid (Endo(..))
 
 -- | Type family that converts a type level list into a function type:
 --
 -- @'ParamFun' ['Char', 'Int', 'Bool'] r@ =
 -- @'Char' -> 'Int' -> 'Bool' -> 'String' -> r@
-#if MIN_VERSION_base(4,7,0)
-type family ParamFun (l :: [*]) r where
+type family ParamFun (l :: [Type]) r where
     ParamFun '[] r = String -> r
     ParamFun (h ': t) r = h -> ParamFun t r
-#else
-type family ParamFun (l :: [*]) r
-type instance ParamFun '[] r = String -> r
-type instance ParamFun (h ': t) r = h -> ParamFun t r
-#endif
 
 -- | Sets of parameters to generate the tree from.
-data Params :: [*] -> * where
+data Params :: [Type] -> Type where
     Nil :: Params '[]
     Sets :: [Params l] -> Params l
     Param :: Eq r
@@ -62,7 +54,7 @@
           -> Params l
           -> Params (r ': l)
 
-data Tree :: [*] -> * where
+data Tree :: [Type] -> Type where
     None :: Tree '[]
     Empty :: Tree l
     Grouped :: Eq r
@@ -138,7 +130,7 @@
 -- The result is \"axy\" being used in groups where the \"Bool\" parameter is
 -- @True@, if the \"Bool\" parameter is @False@ only \"a\" is used.
 paramSets :: [Params r -> Params l] -> Params r -> Params l
-paramSets prefixes rest = Sets $ map ($rest) prefixes
+paramSets prefixes rest = Sets $ map ($ rest) prefixes
 
 trim :: [Tree l] -> Tree l
 trim [] = Empty
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -2,6 +2,7 @@
 =========
 [![BSD3](https://img.shields.io/badge/License-BSD-blue.svg)](https://en.wikipedia.org/wiki/BSD_License)
 [![Hackage](https://img.shields.io/hackage/v/paramtree.svg)](https://hackage.haskell.org/package/paramtree)
+[![hackage-ci](https://matrix.hackage.haskell.org/api/v2/packages/paramtree/badge)](https://matrix.hackage.haskell.org/#/package/paramtree)
 [![Build Status](https://travis-ci.org/merijn/paramtree.svg)](https://travis-ci.org/merijn/paramtree)
 
 **ParamTree** library for generating labelled test/benchmark trees from sets of
@@ -18,9 +19,9 @@
 genTestCase :: Int -> Bool -> Char -> String -> TestTree
 genTestCase i b c name = testCase name $ {- your code here -}
 
-params = 'simpleParam' \"Int\" [1,2]
-       . 'simpleParam' \"Bool\" [True]
-       . 'simpleParam' \"Char\" "xyz"
+params = simpleParam "Int" [1,2]
+       . simpleParam "Bool" [True]
+       . simpleParam "Char" "xyz"
 
 main :: IO ()
 main = defaultMain $ testTree genTestCase params
diff --git a/paramtree.cabal b/paramtree.cabal
--- a/paramtree.cabal
+++ b/paramtree.cabal
@@ -1,12 +1,12 @@
 Name:               paramtree
-Version:            0.1.1.1
+Version:            0.1.2
 
 Homepage:           https://github.com/merijn/paramtree
 Bug-Reports:        https://github.com/merijn/paramtree/issues
 
 Author:             Merijn Verstraaten
 Maintainer:         Merijn Verstraaten <merijn@inconsistent.nl>
-Copyright:          Copyright © 2017 Merijn Verstraaten
+Copyright:          Copyright © 2017-2023 Merijn Verstraaten
 
 License:            BSD3
 License-File:       LICENSE
@@ -14,8 +14,9 @@
 Category:           Development, Benchmarking, Testing
 Cabal-Version:      >= 1.10
 Build-Type:         Simple
-Tested-With:        GHC == 7.6.3, GHC == 7.8.4, GHC == 7.10.3, GHC == 8.0.2,
-                    GHC == 8.2.2, GHC == 8.4.3, GHC == 8.6.1
+Tested-With:        GHC == 8.0.2, GHC == 8.2.2, GHC == 8.4.4, GHC == 8.6.5,
+                    GHC == 8.8.4, GHC == 8.10.7, GHC == 9.0.2, GHC == 9.2.8,
+                    GHC == 9.4.5, GHC == 9.6.2
 
 Extra-Source-Files: README.md tests/*.golden
 
@@ -40,7 +41,7 @@
                         TypeFamilies
                         TypeOperators
 
-  Build-Depends:        base >= 4.6 && < 5
+  Build-Depends:        base >= 4.9 && < 5
                ,        containers >= 0.4 && < 0.7
 
 Test-Suite test
@@ -53,8 +54,8 @@
                         DataKinds
   Build-Depends:        base
                ,        paramtree
-               ,        bytestring >= 0.10 && < 0.11
-               ,        tasty >= 0.11 && < 1.2
+               ,        bytestring >= 0.10 && < 0.13
+               ,        tasty >= 0.11 && < 1.5
                ,        tasty-golden >= 2.0 && < 2.4
                ,        tasty-hunit >= 0.9 && < 0.11
                ,        temporary >= 1.2 && < 1.4
@@ -62,7 +63,3 @@
 Source-Repository head
   Type:     git
   Location: ssh://github.com:merijn/paramtree.git
-
-Source-Repository head
-  Type:     mercurial
-  Location: https://bitbucket.org/merijnv/paramtree