diff --git a/Network/Wai/Application/Classic/CGI.hs b/Network/Wai/Application/Classic/CGI.hs
--- a/Network/Wai/Application/Classic/CGI.hs
+++ b/Network/Wai/Application/Classic/CGI.hs
@@ -24,6 +24,9 @@
 import System.IO
 import System.Process
 
+-- $setup
+-- >>> :set -XOverloadedStrings
+
 ----------------------------------------------------------------
 
 type ENVVARS = [(String,String)]
diff --git a/Network/Wai/Application/Classic/Path.hs b/Network/Wai/Application/Classic/Path.hs
--- a/Network/Wai/Application/Classic/Path.hs
+++ b/Network/Wai/Application/Classic/Path.hs
@@ -15,6 +15,9 @@
 import Data.String
 import Data.Word
 
+-- $setup
+-- >>> :set -XOverloadedStrings
+
 ----------------------------------------------------------------
 
 -- | File path.
diff --git a/test/doctests.hs b/test/doctests.hs
deleted file mode 100644
--- a/test/doctests.hs
+++ /dev/null
@@ -1,9 +0,0 @@
-module Main where
-
-import Test.DocTest
-
-main :: IO ()
-main = doctest [
-    "-XOverloadedStrings"
-  , "Network/Wai/Application/Classic.hs"
-  ]
diff --git a/wai-app-file-cgi.cabal b/wai-app-file-cgi.cabal
--- a/wai-app-file-cgi.cabal
+++ b/wai-app-file-cgi.cabal
@@ -1,108 +1,105 @@
-Name:                   wai-app-file-cgi
-Version:                3.1.10
-Author:                 Kazu Yamamoto <kazu@iij.ad.jp>
-Maintainer:             Kazu Yamamoto <kazu@iij.ad.jp>
-License:                BSD3
-License-File:           LICENSE
-Synopsis:               File/CGI/Rev Proxy App of WAI
-Description:            This WAI application library handles static files,
-                        executes CGI scripts, and serves as a reverse proxy
-                        (including EventSource).
-Homepage:               http://www.mew.org/~kazu/proj/mighttpd/
-Category:               Web, Yesod
-Cabal-Version:          >= 1.10
-Build-Type:             Simple
-Extra-Source-Files:     test/cgi-bin/broken
-                        test/cgi-bin/echo-env
-                        test/data/post
-                        test/html/index.html
-                        test/html/ja/index.html.ja
-                        test/html/no_extension
-                        test/html/redirect/index.html
-Library
-  Default-Language:     Haskell2010
-  GHC-Options:          -Wall
-  Exposed-Modules:      Network.Wai.Application.Classic
-  Other-Modules:        Network.Wai.Application.Classic.CGI
-                        Network.Wai.Application.Classic.Conduit
-                        Network.Wai.Application.Classic.Def
-                        Network.Wai.Application.Classic.EventSource
-                        Network.Wai.Application.Classic.Field
-                        Network.Wai.Application.Classic.File
-                        Network.Wai.Application.Classic.FileInfo
-                        Network.Wai.Application.Classic.Header
-                        Network.Wai.Application.Classic.Lang
-                        Network.Wai.Application.Classic.Path
-                        Network.Wai.Application.Classic.Redirect
-                        Network.Wai.Application.Classic.Status
-                        Network.Wai.Application.Classic.Types
-                        Network.Wai.Application.Classic.RevProxy
+cabal-version:      >=1.10
+name:               wai-app-file-cgi
+version:            3.1.11
+license:            BSD3
+license-file:       LICENSE
+maintainer:         Kazu Yamamoto <kazu@iij.ad.jp>
+author:             Kazu Yamamoto <kazu@iij.ad.jp>
+homepage:           http://www.mew.org/~kazu/proj/mighttpd/
+synopsis:           File/CGI/Rev Proxy App of WAI
+description:
+    This WAI application library handles static files,
+    executes CGI scripts, and serves as a reverse proxy
+    (including EventSource).
 
-  Build-Depends:        base >= 4.9 && < 5
-                      , array
-                      , attoparsec >= 0.10.0.0
-                      , attoparsec-conduit
-                      , bytestring
-                      , case-insensitive
-                      , conduit >= 1.1
-                      , conduit-extra
-                      , containers
-                      , data-default-class
-                      , directory
-                      , filepath
-                      , http-client >= 0.5
-                      , http-conduit >= 2.1
-                      , http-date
-                      , http-types >= 0.7
-                      , mime-types
-                      , network
-                      , process
-                      , sockaddr
-                      , static-hash
-                      , text
-                      , transformers
-                      , unix
-                      , wai >= 3.2 && < 3.3
-                      , wai-conduit
-                      , warp >= 3.3 && < 3.4
-                      , word8
-  if impl(ghc >= 8)
-    Default-Extensions:  Strict StrictData
+category:           Web, Yesod
+build-type:         Simple
+extra-source-files:
+    test/cgi-bin/broken
+    test/cgi-bin/echo-env
+    test/data/post
+    test/html/index.html
+    test/html/ja/index.html.ja
+    test/html/no_extension
+    test/html/redirect/index.html
 
-Test-Suite doctest
-  Type:                 exitcode-stdio-1.0
-  Default-Language:     Haskell2010
-  HS-Source-Dirs:       test
-  Ghc-Options:          -threaded -Wall
-  Main-Is:              doctests.hs
-  Build-Depends:        base >= 4.9 && < 5
-                      , doctest >= 0.9.3
-  if impl(ghc >= 8)
-    Default-Extensions:  Strict StrictData
+source-repository head
+    type:     git
+    location: git://github.com/kazu-yamamoto/wai-app-file-cgi
 
-Test-Suite spec
-  Type:                 exitcode-stdio-1.0
-  Default-Language:     Haskell2010
-  HS-Source-Dirs:       test
-  Ghc-Options:          -threaded -Wall
-  Main-Is:              Spec.hs
-  Other-Modules:        ClassicSpec
-  Build-Depends:        base >= 4.9 && < 5
-                      , bytestring
-                      , conduit >= 1.1
-                      , conduit-extra
-                      , directory
-                      , filepath
-                      , hspec >= 1.3
-                      , http-types
-                      , unix
-                      , wai >= 3.2 && < 3.3
-                      , wai-app-file-cgi
-                      , warp >= 3.3 && < 3.4
-                      , HTTP
-  if impl(ghc >= 8)
-    Default-Extensions:  Strict StrictData
+library
+    exposed-modules:  Network.Wai.Application.Classic
+    other-modules:
+        Network.Wai.Application.Classic.CGI
+        Network.Wai.Application.Classic.Conduit
+        Network.Wai.Application.Classic.Def
+        Network.Wai.Application.Classic.EventSource
+        Network.Wai.Application.Classic.Field
+        Network.Wai.Application.Classic.File
+        Network.Wai.Application.Classic.FileInfo
+        Network.Wai.Application.Classic.Header
+        Network.Wai.Application.Classic.Lang
+        Network.Wai.Application.Classic.Path
+        Network.Wai.Application.Classic.Redirect
+        Network.Wai.Application.Classic.Status
+        Network.Wai.Application.Classic.Types
+        Network.Wai.Application.Classic.RevProxy
 
-Source-Repository head
-  Type:                 git
-  Location:             git://github.com/kazu-yamamoto/wai-app-file-cgi
+    default-language: Haskell2010
+    ghc-options:      -Wall
+    build-depends:
+        base >=4.9 && <5,
+        array,
+        attoparsec >=0.10.0.0,
+        bytestring,
+        case-insensitive,
+        conduit >=1.1,
+        conduit-extra,
+        containers,
+        data-default-class,
+        directory,
+        filepath,
+        http-client >=0.5,
+        http-conduit >=2.1,
+        http-date,
+        http-types >=0.7,
+        mime-types,
+        network,
+        process,
+        sockaddr,
+        static-hash,
+        text,
+        transformers,
+        unix,
+        wai >=3.2 && <3.3,
+        wai-conduit,
+        warp >=3.4 && <3.5,
+        word8
+
+    if impl(ghc >=8)
+        default-extensions: Strict StrictData
+
+test-suite spec
+    type:             exitcode-stdio-1.0
+    main-is:          Spec.hs
+    hs-source-dirs:   test
+    other-modules:    ClassicSpec
+    default-language: Haskell2010
+    ghc-options:      -threaded -Wall
+    build-depends:
+        base >=4.9 && <5,
+        bytestring,
+        conduit >=1.1,
+        conduit-extra,
+        directory,
+        filepath,
+        hspec >=1.3,
+        http-types,
+        unix,
+        wai >=3.2 && <3.3,
+        wai-app-file-cgi,
+        warp >=3.4 && <3.5,
+        HTTP
+
+    if impl(ghc >=8)
+        default-extensions: Strict StrictData
