diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -7,8 +7,8 @@
 functions in `megaparsec-tests` which can be used by other test suites, for
 example in the `parser-combinators-tests` package.
 
-Version of `megaparsec-tests` will be kept in sync with versions of
-`megaparsec` from now on.
+The version number of `megaparsec-tests` will be kept in sync with versions
+of `megaparsec` from now on.
 
 ## License
 
diff --git a/megaparsec-tests.cabal b/megaparsec-tests.cabal
--- a/megaparsec-tests.cabal
+++ b/megaparsec-tests.cabal
@@ -1,11 +1,11 @@
 cabal-version:   1.18
 name:            megaparsec-tests
-version:         9.0.1
+version:         9.1.0
 license:         BSD2
 license-file:    LICENSE.md
 maintainer:      Mark Karpov <markkarpov92@gmail.com>
 author:          Megaparsec contributors
-tested-with:     ghc ==8.6.5 ghc ==8.8.4 ghc ==8.10.2
+tested-with:     ghc ==8.8.4 ghc ==8.10.4 ghc ==9.0.1
 homepage:        https://github.com/mrkkrp/megaparsec
 bug-reports:     https://github.com/mrkkrp/megaparsec/issues
 synopsis:        Test utilities and the test suite of Megaparsec
@@ -25,13 +25,13 @@
     default-language: Haskell2010
     build-depends:
         QuickCheck >=2.10 && <2.15,
-        base >=4.12 && <5.0,
-        bytestring >=0.2 && <0.11,
+        base >=4.13 && <5.0,
+        bytestring >=0.2 && <0.12,
         containers >=0.5 && <0.7,
         hspec >=2.0 && <3.0,
         hspec-expectations >=0.8 && <0.9,
         hspec-megaparsec >=2.0 && <3.0,
-        megaparsec ==9.0.1,
+        megaparsec ==9.1.0,
         mtl >=2.2.2 && <3.0,
         text >=0.2 && <1.3,
         transformers >=0.4 && <0.6
@@ -63,15 +63,15 @@
     default-language: Haskell2010
     build-depends:
         QuickCheck >=2.10 && <2.15,
-        base >=4.12 && <5.0,
-        bytestring >=0.2 && <0.11,
+        base >=4.13 && <5.0,
+        bytestring >=0.2 && <0.12,
         case-insensitive >=1.2 && <1.3,
         containers >=0.5 && <0.7,
         hspec >=2.0 && <3.0,
         hspec-expectations >=0.8 && <0.9,
         hspec-megaparsec >=2.0 && <3.0,
-        megaparsec ==9.0.1,
-        megaparsec-tests -any,
+        megaparsec ==9.1.0,
+        megaparsec-tests,
         mtl >=2.2.2 && <3.0,
         parser-combinators >=1.0 && <2.0,
         scientific >=0.3.1 && <0.4,
diff --git a/src/Test/Hspec/Megaparsec/AdHoc.hs b/src/Test/Hspec/Megaparsec/AdHoc.hs
--- a/src/Test/Hspec/Megaparsec/AdHoc.hs
+++ b/src/Test/Hspec/Megaparsec/AdHoc.hs
@@ -81,8 +81,8 @@
 ----------------------------------------------------------------------------
 -- Helpers to run parsers
 
--- | Apply parser to given input. This is a specialized version of 'parse'
--- that assumes empty file name.
+-- | Apply the parser to the given input. This is a specialized version of
+-- 'parse' that assumes empty file name.
 prs ::
   -- | Parser to run
   Parser a ->
@@ -92,7 +92,8 @@
   Either (ParseErrorBundle String Void) a
 prs p = parse p ""
 
--- | Just like 'prs', but allows to inspect the final state of the parser.
+-- | Just like 'prs', but allows us to inspect the final state of the
+-- parser.
 prs' ::
   -- | Parser to run
   Parser a ->
diff --git a/tests/Text/Megaparsec/Byte/LexerSpec.hs b/tests/Text/Megaparsec/Byte/LexerSpec.hs
--- a/tests/Text/Megaparsec/Byte/LexerSpec.hs
+++ b/tests/Text/Megaparsec/Byte/LexerSpec.hs
@@ -1,4 +1,3 @@
-{-# LANGUAGE CPP #-}
 {-# LANGUAGE OverloadedStrings #-}
 
 module Text.Megaparsec.Byte.LexerSpec (spec) where
@@ -18,10 +17,6 @@
 import Text.Megaparsec
 import qualified Text.Megaparsec.Byte as B
 import Text.Megaparsec.Byte.Lexer
-
-#if !MIN_VERSION_base(4,13,0)
-import Data.Semigroup ((<>))
-#endif
 
 type Parser = Parsec Void ByteString
 
diff --git a/tests/Text/Megaparsec/ByteSpec.hs b/tests/Text/Megaparsec/ByteSpec.hs
--- a/tests/Text/Megaparsec/ByteSpec.hs
+++ b/tests/Text/Megaparsec/ByteSpec.hs
@@ -1,4 +1,3 @@
-{-# LANGUAGE CPP #-}
 {-# LANGUAGE OverloadedStrings #-}
 
 module Text.Megaparsec.ByteSpec (spec) where
@@ -16,10 +15,6 @@
 import Test.QuickCheck
 import Text.Megaparsec
 import Text.Megaparsec.Byte
-
-#if !MIN_VERSION_base(4,13,0)
-import Data.Semigroup ((<>))
-#endif
 
 type Parser = Parsec Void ByteString
 
diff --git a/tests/Text/Megaparsec/Char/LexerSpec.hs b/tests/Text/Megaparsec/Char/LexerSpec.hs
--- a/tests/Text/Megaparsec/Char/LexerSpec.hs
+++ b/tests/Text/Megaparsec/Char/LexerSpec.hs
@@ -1,4 +1,3 @@
-{-# LANGUAGE CPP #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE MultiWayIf #-}
 {-# LANGUAGE TupleSections #-}
@@ -21,10 +20,6 @@
 import Text.Megaparsec
 import qualified Text.Megaparsec.Char as C
 import Text.Megaparsec.Char.Lexer
-
-#if !MIN_VERSION_base(4,13,0)
-import Data.Semigroup ((<>))
-#endif
 
 spec :: Spec
 spec = do
diff --git a/tests/Text/Megaparsec/CharSpec.hs b/tests/Text/Megaparsec/CharSpec.hs
--- a/tests/Text/Megaparsec/CharSpec.hs
+++ b/tests/Text/Megaparsec/CharSpec.hs
@@ -1,4 +1,3 @@
-{-# LANGUAGE CPP #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
 module Text.Megaparsec.CharSpec (spec) where
@@ -13,10 +12,6 @@
 import Test.QuickCheck
 import Text.Megaparsec
 import Text.Megaparsec.Char
-
-#if !MIN_VERSION_base(4,13,0)
-import Data.Semigroup ((<>))
-#endif
 
 instance Arbitrary GeneralCategory where
   arbitrary = elements [minBound .. maxBound]
diff --git a/tests/Text/Megaparsec/DebugSpec.hs b/tests/Text/Megaparsec/DebugSpec.hs
--- a/tests/Text/Megaparsec/DebugSpec.hs
+++ b/tests/Text/Megaparsec/DebugSpec.hs
@@ -1,4 +1,3 @@
-{-# LANGUAGE CPP #-}
 {-# LANGUAGE OverloadedStrings #-}
 
 module Text.Megaparsec.DebugSpec (spec) where
@@ -11,15 +10,11 @@
 import Text.Megaparsec.Char
 import Text.Megaparsec.Debug
 
-#if !MIN_VERSION_base(4,13,0)
-import Data.Semigroup ((<>))
-#endif
-
 spec :: Spec
 spec = do
   describe "dbg" $ do
-    -- NOTE We don't test properties here to avoid flood of debugging output
-    -- when the test runs.
+    -- NOTE We don't test properties here to avoid a flood of debugging
+    -- output when the test runs.
     context "when inner parser succeeds consuming input" $ do
       it "has no effect on how parser works" $ do
         let p = dbg "char" (char 'a')
diff --git a/tests/Text/Megaparsec/ErrorSpec.hs b/tests/Text/Megaparsec/ErrorSpec.hs
--- a/tests/Text/Megaparsec/ErrorSpec.hs
+++ b/tests/Text/Megaparsec/ErrorSpec.hs
@@ -1,4 +1,3 @@
-{-# LANGUAGE CPP #-}
 {-# LANGUAGE OverloadedStrings #-}
 
 module Text.Megaparsec.ErrorSpec (spec) where
@@ -15,10 +14,6 @@
 import Test.QuickCheck
 import Text.Megaparsec
 
-#if !MIN_VERSION_base(4,13,0)
-import Data.Semigroup ((<>))
-#endif
-
 spec :: Spec
 spec = do
   describe "Semigroup instance of ParseError" $
@@ -257,7 +252,7 @@
 ----------------------------------------------------------------------------
 -- Helpers
 
--- | Custom error component to test continuous highlighting for custom
+-- | A custom error component to test continuous highlighting for custom
 -- components.
 newtype CustomErr = CustomErr Int
   deriving (Eq, Ord, Show)
diff --git a/tests/Text/Megaparsec/PosSpec.hs b/tests/Text/Megaparsec/PosSpec.hs
--- a/tests/Text/Megaparsec/PosSpec.hs
+++ b/tests/Text/Megaparsec/PosSpec.hs
@@ -1,5 +1,3 @@
-{-# LANGUAGE CPP #-}
-
 module Text.Megaparsec.PosSpec (spec) where
 
 import Control.Exception (evaluate)
@@ -9,10 +7,6 @@
 import Test.Hspec.Megaparsec.AdHoc ()
 import Test.QuickCheck
 import Text.Megaparsec.Pos
-
-#if !MIN_VERSION_base(4,13,0)
-import Data.Semigroup ((<>))
-#endif
 
 spec :: Spec
 spec = do
diff --git a/tests/Text/Megaparsec/StreamSpec.hs b/tests/Text/Megaparsec/StreamSpec.hs
--- a/tests/Text/Megaparsec/StreamSpec.hs
+++ b/tests/Text/Megaparsec/StreamSpec.hs
@@ -1,4 +1,3 @@
-{-# LANGUAGE CPP #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE ScopedTypeVariables #-}
@@ -22,10 +21,6 @@
 import Test.QuickCheck
 import Text.Megaparsec
 
-#if !MIN_VERSION_base(4,13,0)
-import Data.Semigroup ((<>))
-#endif
-
 spec :: Spec
 spec = do
   describe "String instance of Stream" $ do
@@ -591,7 +586,7 @@
                in pst'
         reachOffsetNoLine o' s `shouldBe` reachOffsetNoLine o' s'
 
--- | Get next tab position given tab width and current column.
+-- | Get the next tab position given the tab width and the current column.
 toNextTab ::
   -- | Tab width
   Pos ->