diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -2,12 +2,23 @@
 
 <!-- This ChangeLog follows a format specified by: https://keepachangelog.com/en/1.0.0/ -->
 
+## [1.1.1] - 2021-06-11
+
+### Added
+
+- Added `--version` switch for the `bech32` command.
+
+### Changed
+
+- Upgraded CI to build with Cabal 3.4.0.0 and GHC 8.10.4.
+- Update version constraints for GHC 9.0.1.
+
 ## [1.1.0] - 2020-07-08
 
-### Added 
+### Added
 
 - Added `bech32` command-line for easy conversions in the console.
-  
+
   ```console
   Usage: bech32 [PREFIX]
     Convert to and from bech32 strings. Data are read from standard input.
@@ -60,6 +71,6 @@
 
 ## [1.0.0] - 2019-09-27
 
-### Added 
+### Added
 
 - Initial release pulled from https://github.com/input-output-hk/cardano-wallet
diff --git a/app/Main.hs b/app/Main.hs
--- a/app/Main.hs
+++ b/app/Main.hs
@@ -11,7 +11,7 @@
 import Control.Arrow
     ( left, right )
 import Control.Monad
-    ( guard )
+    ( guard, void )
 import Data.ByteArray.Encoding
     ( convertFromBase, convertToBase )
 import Data.ByteString.Base58
@@ -22,25 +22,34 @@
     ( maybeToEither )
 import Data.Maybe
     ( fromJust )
+import Data.Version
+    ( showVersion )
 import Options.Applicative
     ( Parser
     , ParserInfo
     , argument
     , customExecParser
     , eitherReader
+    , flag
     , footerDoc
+    , help
     , helpDoc
     , helper
+    , hidden
     , info
+    , long
     , metavar
     , optional
     , prefs
     , progDesc
+    , short
     , showHelpOnEmpty
     , (<|>)
     )
 import Options.Applicative.Help.Pretty
     ( bold, hsep, indent, text, underline, vsep )
+import Paths_bech32
+    ( version )
 import System.IO
     ( BufferMode (..), Handle, hSetBuffering, stderr, stdin, stdout )
 
@@ -54,9 +63,12 @@
 main :: IO ()
 main = setup >> parse >>= run
 
-newtype Cmd = Cmd
-  { prefix :: Maybe HumanReadablePart
-  } deriving (Show)
+data Cmd
+    = RunCmd
+    { prefix :: Maybe HumanReadablePart
+    }
+    | VersionCmd
+    deriving (Show)
 
 -- | Enable ANSI colors on Windows and correct output buffering
 setup :: IO ()
@@ -100,8 +112,16 @@
         ]
 
     cmd :: Parser Cmd
-    cmd = Cmd <$> optional hrpArgument
+    cmd = (RunCmd <$> optional hrpArgument) <|> (VersionCmd <$ versionFlag)
 
+versionFlag :: Parser ()
+versionFlag = void . flag False True $ mconcat
+    [ long "version"
+    , short 'v'
+    , help "output version information and exit"
+    , hidden
+    ]
+
 -- | Parse a 'HumanReadablePart' as an argument.
 hrpArgument :: Parser HumanReadablePart
 hrpArgument = argument (eitherReader reader) $ mconcat
@@ -121,11 +141,13 @@
 
 -- | Run a Command in IO
 run :: Cmd -> IO ()
-run Cmd{prefix} = do
-    source <- T.decodeUtf8 . B8.filter (/= '\n') <$> B8.hGetContents stdin
-    case prefix of
-        Nothing  -> runDecode source
-        Just hrp -> runEncode hrp source
+run cmd = case cmd of
+    VersionCmd -> putStrLn $ showVersion version
+    RunCmd {prefix} -> do
+        source <- T.decodeUtf8 . B8.filter (/= '\n') <$> B8.hGetContents stdin
+        case prefix of
+            Nothing  -> runDecode source
+            Just hrp -> runEncode hrp source
   where
     runDecode source =
         case Bech32.decodeLenient source of
diff --git a/bech32.cabal b/bech32.cabal
--- a/bech32.cabal
+++ b/bech32.cabal
@@ -1,5 +1,5 @@
 name:          bech32
-version:       1.1.0
+version:       1.1.1
 synopsis:      Implementation of the Bech32 cryptocurrency address format (BIP 0173).
 description:   Implementation of the Bech32 cryptocurrency address format documented in the
                BIP (Bitcoin Improvement Proposal) 0173.
@@ -19,15 +19,15 @@
   type:     git
   location: https://github.com/input-output-hk/bech32.git
 
-flag werror
-    description: Enable `-Werror`
-    default: False
-    manual: True
-
 flag release
-  description: Compile executables for a release.
+  description: Strict compiler warning checks.
+  default: False
   manual: True
+
+flag static
+  description: Try to build a static executable.
   default: False
+  manual: True
 
 library
   default-language:
@@ -36,15 +36,12 @@
       NoImplicitPrelude
       OverloadedStrings
   ghc-options:
-      -Wall
-      -Wcompat
-      -fwarn-redundant-constraints
-  if (flag(werror))
-    ghc-options:
-      -Werror
+      -Wall -Wcompat -fwarn-redundant-constraints
+  if flag(release)
+    ghc-options: -Werror
   build-depends:
       array
-    , base >= 4.11.1.0 && < 4.15
+    , base >= 4.11.1.0 && <5
     , bytestring
     , containers
     , extra
@@ -61,9 +58,8 @@
       Paths_bech32
   hs-source-dirs:
       app
-  ghc-options: -Wall -Wcompat -fwarn-redundant-constraints -threaded -rtsopts -with-rtsopts=-N
   build-depends:
-      base >=4.7 && <5
+      base
     , base58-bytestring
     , bech32
     , bytestring
@@ -71,8 +67,13 @@
     , memory
     , optparse-applicative
     , text
+  ghc-options:
+      -Wall -Wcompat -fwarn-redundant-constraints
+      -threaded -rtsopts -with-rtsopts=-N
   if flag(release)
-    ghc-options: -Werror -static -O2
+    ghc-options: -Werror
+  if flag(static)
+    ghc-options: -static
     cc-options: -static
     ld-options: -static -pthread
   default-language: Haskell2010
@@ -85,11 +86,10 @@
   hs-source-dirs:
       test
   ghc-options:
-      -threaded -rtsopts -with-rtsopts=-N
       -Wall
-  if (flag(werror))
-    ghc-options:
-      -Werror
+      -threaded -rtsopts -with-rtsopts=-N
+  if flag(release)
+    ghc-options: -Werror
   build-depends:
       base
     , base58-bytestring