diff --git a/.travis.yml b/.travis.yml
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,163 +1,181 @@
 # This Travis job script has been generated by a script via
 #
-#   runghc make_travis_yml_2.hs '-o' '.travis.yml' '--ghc-head' '--irc-channel=irc.freenode.org#haskell-lens' '--no-no-tests-no-bench' '--no-unconstrained' 'cabal.project' '--hlint' '--hlint-options=--cpp-define=HLINT' '--allow-failure=7.0.4' '--allow-failure=7.2.2'
+#   haskell-ci '--output=.travis.yml' '--config=cabal.haskell-ci' 'cabal.project'
 #
-# For more information, see https://github.com/hvr/multi-ghc-travis
+# For more information, see https://github.com/haskell-CI/haskell-ci
 #
+# version: 0.3.20190425
+#
 language: c
-sudo: false
-
+dist: xenial
 git:
-  submodules: false  # whether to recursively clone submodules
-
+  # whether to recursively clone submodules
+  submodules: false
 notifications:
   irc:
     channels:
-      - "irc.freenode.org#haskell-lens"
+      - irc.freenode.org#haskell-lens
     skip_join: true
     template:
-      - "\x0313parsers\x03/\x0306%{branch}\x03 \x0314%{commit}\x03 %{build_url} %{message}"
-
+      - "\"\\x0313parsers\\x03/\\x0306%{branch}\\x03 \\x0314%{commit}\\x03 %{build_url} %{message}\""
 cache:
   directories:
     - $HOME/.cabal/packages
     - $HOME/.cabal/store
-
 before_cache:
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/build-reports.log
+  - rm -fv $CABALHOME/packages/hackage.haskell.org/build-reports.log
   # remove files that are regenerated by 'cabal update'
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/00-index.*
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/*.json
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/01-index.cache
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/01-index.tar
-  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/01-index.tar.idx
-
-  - rm -rfv $HOME/.cabal/packages/head.hackage
-
+  - rm -fv $CABALHOME/packages/hackage.haskell.org/00-index.*
+  - rm -fv $CABALHOME/packages/hackage.haskell.org/*.json
+  - rm -fv $CABALHOME/packages/hackage.haskell.org/01-index.cache
+  - rm -fv $CABALHOME/packages/hackage.haskell.org/01-index.tar
+  - rm -fv $CABALHOME/packages/hackage.haskell.org/01-index.tar.idx
+  - rm -rfv $CABALHOME/packages/head.hackage
 matrix:
   include:
-    - compiler: "ghc-8.6.1"
+    - compiler: ghc-8.8.1
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.8.1","cabal-install-3.0"]}}
       env: GHCHEAD=true
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-head,ghc-8.6.1], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.4.3"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-8.4.3], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.2.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-8.2.2], sources: [hvr-ghc]}}
-    - compiler: "ghc-8.0.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-8.0.2], sources: [hvr-ghc]}}
-    - compiler: "ghc-7.10.3"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-7.10.3], sources: [hvr-ghc]}}
-    - compiler: "ghc-7.8.4"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-7.8.4], sources: [hvr-ghc]}}
-    - compiler: "ghc-7.6.3"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-7.6.3], sources: [hvr-ghc]}}
-    - compiler: "ghc-7.4.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-7.4.2], sources: [hvr-ghc]}}
-    - compiler: "ghc-7.2.2"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-7.2.2], sources: [hvr-ghc]}}
-    - compiler: "ghc-7.0.4"
-    # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.2,ghc-7.0.4], sources: [hvr-ghc]}}
-    - compiler: "ghc-head"
+    - compiler: ghc-8.6.5
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.6.5","cabal-install-2.4"]}}
+    - compiler: ghc-8.4.4
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.4.4","cabal-install-2.4"]}}
+    - compiler: ghc-8.2.2
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.2.2","cabal-install-2.4"]}}
+    - compiler: ghc-8.0.2
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.0.2","cabal-install-2.4"]}}
+    - compiler: ghc-7.10.3
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-7.10.3","cabal-install-2.4"]}}
+    - compiler: ghc-7.8.4
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-7.8.4","cabal-install-2.4"]}}
+    - compiler: ghc-7.6.3
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-7.6.3","cabal-install-2.4"]}}
+    - compiler: ghc-7.4.2
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-7.4.2","cabal-install-2.4"]}}
+    - compiler: ghc-7.2.2
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-7.2.2","cabal-install-2.4"]}}
+    - compiler: ghc-7.0.4
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-7.0.4","cabal-install-2.4"]}}
+    - compiler: ghc-head
+      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-head","cabal-install-head"]}}
       env: GHCHEAD=true
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-head,ghc-head], sources: [hvr-ghc]}}
-
   allow_failures:
-    - compiler: "ghc-head"
-    - compiler: "ghc-7.0.4"
-    - compiler: "ghc-7.2.2"
-    - compiler: "ghc-8.6.1"
-
+    - compiler: ghc-head
+    - compiler: ghc-7.0.4
+    - compiler: ghc-7.2.2
+    - compiler: ghc-8.8.1
 before_install:
-  - HC=${CC}
-  - HCPKG=${HC/ghc/ghc-pkg}
+  - HC=$(echo "/opt/$CC/bin/ghc" | sed 's/-/\//')
+  - HCPKG="$HC-pkg"
   - unset CC
-  - ROOTDIR=$(pwd)
-  - mkdir -p $HOME/.local/bin
-  - "PATH=/opt/ghc/bin:/opt/ghc-ppa-tools/bin:$HOME/local/bin:$PATH"
+  - CABAL=/opt/ghc/bin/cabal
+  - CABALHOME=$HOME/.cabal
+  - export PATH="$CABALHOME/bin:$PATH"
+  - TOP=$(pwd)
   - HCNUMVER=$(( $(${HC} --numeric-version|sed -E 's/([0-9]+)\.([0-9]+)\.([0-9]+).*/\1 * 10000 + \2 * 100 + \3/') ))
   - echo $HCNUMVER
-
+  - CABAL="$CABAL -vnormal+nowrap+markoutput"
+  - set -o pipefail
+  - |
+    echo 'function blue(s) { printf "\033[0;34m" s "\033[0m " }'           >> .colorful.awk
+    echo 'BEGIN { state = "output"; }'                                     >> .colorful.awk
+    echo '/^-----BEGIN CABAL OUTPUT-----$/ { state = "cabal" }'            >> .colorful.awk
+    echo '/^-----END CABAL OUTPUT-----$/ { state = "output" }'             >> .colorful.awk
+    echo '!/^(-----BEGIN CABAL OUTPUT-----|-----END CABAL OUTPUT-----)/ {' >> .colorful.awk
+    echo '  if (state == "cabal") {'                                       >> .colorful.awk
+    echo '    print blue($0)'                                              >> .colorful.awk
+    echo '  } else {'                                                      >> .colorful.awk
+    echo '    print $0'                                                    >> .colorful.awk
+    echo '  }'                                                             >> .colorful.awk
+    echo '}'                                                               >> .colorful.awk
+  - cat .colorful.awk
+  - |
+    color_cabal_output () {
+      awk -f $TOP/.colorful.awk
+    }
+  - echo text | color_cabal_output
 install:
-  - cabal --version
+  - ${CABAL} --version
   - echo "$(${HC} --version) [$(${HC} --print-project-git-commit-id 2> /dev/null || echo '?')]"
-  - BENCH=${BENCH---enable-benchmarks}
-  - TEST=${TEST---enable-tests}
-  - HADDOCK=${HADDOCK-true}
-  - UNCONSTRAINED=${UNCONSTRAINED-true}
-  - NOINSTALLEDCONSTRAINTS=${NOINSTALLEDCONSTRAINTS-false}
+  - TEST=--enable-tests
+  - BENCH=--enable-benchmarks
   - GHCHEAD=${GHCHEAD-false}
-  - travis_retry cabal update -v
-  - "sed -i.bak 's/^jobs:/-- jobs:/' ${HOME}/.cabal/config"
-  - rm -fv cabal.project cabal.project.local
-  # Overlay Hackage Package Index for GHC HEAD: https://github.com/hvr/head.hackage
+  - rm -f $CABALHOME/config
   - |
+    echo "verbose: normal +nowrap +markoutput"          >> $CABALHOME/config
+    echo "remote-build-reporting: anonymous"            >> $CABALHOME/config
+    echo "remote-repo-cache: $CABALHOME/packages"       >> $CABALHOME/config
+    echo "logs-dir:          $CABALHOME/logs"           >> $CABALHOME/config
+    echo "world-file:        $CABALHOME/world"          >> $CABALHOME/config
+    echo "extra-prog-path:   $CABALHOME/bin"            >> $CABALHOME/config
+    echo "symlink-bindir:    $CABALHOME/bin"            >> $CABALHOME/config
+    echo "installdir:        $CABALHOME/bin"            >> $CABALHOME/config
+    echo "build-summary:     $CABALHOME/logs/build.log" >> $CABALHOME/config
+    echo "store-dir:         $CABALHOME/store"          >> $CABALHOME/config
+    echo "install-dirs user"                            >> $CABALHOME/config
+    echo "  prefix: $CABALHOME"                         >> $CABALHOME/config
+    echo "repository hackage.haskell.org"               >> $CABALHOME/config
+    echo "  url: http://hackage.haskell.org/"           >> $CABALHOME/config
+  - |
     if $GHCHEAD; then
-      sed -i 's/-- allow-newer: .*/allow-newer: *:base/' ${HOME}/.cabal/config
-      for pkg in $($HCPKG list --simple-output); do pkg=$(echo $pkg | sed 's/-[^-]*$//'); sed -i "s/allow-newer: /allow-newer: *:$pkg, /" ${HOME}/.cabal/config; done
-
-      echo 'repository head.hackage'                                                        >> ${HOME}/.cabal/config
-      echo '   url: http://head.hackage.haskell.org/'                                       >> ${HOME}/.cabal/config
-      echo '   secure: True'                                                                >> ${HOME}/.cabal/config
-      echo '   root-keys: 07c59cb65787dedfaef5bd5f987ceb5f7e5ebf88b904bbd4c5cbdeb2ff71b740' >> ${HOME}/.cabal/config
-      echo '              2e8555dde16ebd8df076f1a8ef13b8f14c66bad8eafefd7d9e37d0ed711821fb' >> ${HOME}/.cabal/config
-      echo '              8f79fd2389ab2967354407ec852cbe73f2e8635793ac446d09461ffb99527f6e' >> ${HOME}/.cabal/config
-      echo '   key-threshold: 3'                                                            >> ${HOME}/.cabal.config
-
-      grep -Ev -- '^\s*--' ${HOME}/.cabal/config | grep -Ev '^\s*$'
-
-      cabal new-update head.hackage -v
+    echo "allow-newer: $($HCPKG list --simple-output | sed -E 's/([a-zA-Z-]+)-[0-9.]+/*:\1/g')" >> $CABALHOME/config
+    
+    echo "repository head.hackage"                                                        >> $CABALHOME/config
+    echo "   url: http://head.hackage.haskell.org/"                                       >> $CABALHOME/config
+    echo "   secure: True"                                                                >> $CABALHOME/config
+    echo "   root-keys: 07c59cb65787dedfaef5bd5f987ceb5f7e5ebf88b904bbd4c5cbdeb2ff71b740" >> $CABALHOME/config
+    echo "              2e8555dde16ebd8df076f1a8ef13b8f14c66bad8eafefd7d9e37d0ed711821fb" >> $CABALHOME/config
+    echo "              8f79fd2389ab2967354407ec852cbe73f2e8635793ac446d09461ffb99527f6e" >> $CABALHOME/config
+    echo "   key-threshold: 3"                                                            >> $CABALHOME/config
     fi
-  - grep -Ev -- '^\s*--' ${HOME}/.cabal/config | grep -Ev '^\s*$'
-  - if [ $HCNUMVER -eq 80403 ]; then cabal new-install -w ${HC} -j2 --symlink-bindir=$HOME/.local/bin hlint --constraint='hlint ==2.1.*'; fi
-  - "printf 'packages: \".\"\\n' > cabal.project"
-  - touch cabal.project.local
-  - "if ! $NOINSTALLEDCONSTRAINTS; then for pkg in $($HCPKG list --simple-output); do echo $pkg  | grep -vw -- parsers | sed 's/^/constraints: /' | sed 's/-[^-]*$/ installed/' >> cabal.project.local; done; fi"
+  - cat $CABALHOME/config
+  - rm -fv cabal.project cabal.project.local cabal.project.freeze
+  - travis_retry ${CABAL} v2-update -v
+  - if [ $HCNUMVER -eq 80801 ] ; then ${CABAL} v2-install -w ${HC} -j2 hlint --constraint='hlint ==2.1.*' | color_cabal_output ; fi
+  # Generate cabal.project
+  - rm -rf cabal.project cabal.project.local cabal.project.freeze
+  - touch cabal.project
+  - |
+    echo 'packages: "."' >> cabal.project
+  - |
+    echo "write-ghc-environment-files: always" >> cabal.project
+  - "for pkg in $($HCPKG list --simple-output); do echo $pkg | sed 's/-[^-]*$//' | grep -vE -- '^(parsers)$' | sed 's/^/constraints: /' | sed 's/$/ installed/' >> cabal.project.local; done"
   - cat cabal.project || true
   - cat cabal.project.local || true
-  - if [ -f "./configure.ac" ]; then
-      (cd "." && autoreconf -i);
-    fi
-  - rm -f cabal.project.freeze
-  - cabal new-build -w ${HC} ${TEST} ${BENCH} --project-file="cabal.project" --dep -j2 all
-  - rm -rf .ghc.environment.* "."/dist
-  - DISTDIR=$(mktemp -d /tmp/dist-test.XXXX)
-
-# Here starts the actual work to be performed for the package under test;
-# any command which exits with a non-zero exit code causes the build to fail.
+  - if [ -f "./configure.ac" ]; then (cd "." && autoreconf -i); fi
+  - ${CABAL} v2-freeze -w ${HC} ${TEST} ${BENCH} | color_cabal_output
+  - "cat cabal.project.freeze | sed -E 's/^(constraints: *| *)//' | sed 's/any.//'"
+  - rm  cabal.project.freeze
+  - ${CABAL} v2-build -w ${HC} ${TEST} ${BENCH} --dep -j2 all | color_cabal_output
 script:
-  # test that source-distributions can be generated
-  - (cd "." && cabal sdist)
-  - mv "."/dist/parsers-*.tar.gz ${DISTDIR}/
+  - DISTDIR=$(mktemp -d /tmp/dist-test.XXXX)
+  # Packaging...
+  - ${CABAL} v2-sdist all | color_cabal_output
+  # Unpacking...
+  - mv dist-newstyle/sdist/*.tar.gz ${DISTDIR}/
   - cd ${DISTDIR} || false
   - find . -maxdepth 1 -name '*.tar.gz' -exec tar -xvf '{}' \;
-  - "printf 'packages: parsers-*/*.cabal\\n' > cabal.project"
-  - touch cabal.project.local
-  - "if ! $NOINSTALLEDCONSTRAINTS; then for pkg in $($HCPKG list --simple-output); do echo $pkg  | grep -vw -- parsers | sed 's/^/constraints: /' | sed 's/-[^-]*$/ installed/' >> cabal.project.local; done; fi"
+  # Generate cabal.project
+  - rm -rf cabal.project cabal.project.local cabal.project.freeze
+  - touch cabal.project
+  - |
+    echo 'packages: "parsers-*/*.cabal"' >> cabal.project
+  - |
+    echo "write-ghc-environment-files: always" >> cabal.project
+  - "for pkg in $($HCPKG list --simple-output); do echo $pkg | sed 's/-[^-]*$//' | grep -vE -- '^(parsers)$' | sed 's/^/constraints: /' | sed 's/$/ installed/' >> cabal.project.local; done"
   - cat cabal.project || true
   - cat cabal.project.local || true
-
+  # Building with tests and benchmarks...
   # build & run tests, build benchmarks
-  - cabal new-build -w ${HC} ${TEST} ${BENCH} all
-  - if [ "x$TEST" = "x--enable-tests" ]; then cabal new-test -w ${HC} ${TEST} ${BENCH} all; fi
-
-  # hlint
-  - if [ $HCNUMVER -eq 80403 ]; then (cd parsers-* && hlint --cpp-define=HLINT src); fi
-
-  # cabal check
-  - (cd parsers-* && cabal check)
-
-  # haddock
-  - rm -rf ./dist-newstyle
-  - if $HADDOCK; then cabal new-haddock -w ${HC} ${TEST} ${BENCH} all; else echo "Skipping haddock generation";fi
+  - ${CABAL} v2-build -w ${HC} ${TEST} ${BENCH} all | color_cabal_output
+  # Testing...
+  - ${CABAL} v2-test -w ${HC} ${TEST} ${BENCH} all | color_cabal_output
+  # HLint..
+  - if [ $HCNUMVER -eq 80801 ] ; then (cd parsers-* && hlint --cpp-ansi --cpp-define=HLINT src) ; fi
+  # cabal check...
+  - (cd parsers-* && ${CABAL} -vnormal check)
+  # haddock...
+  - ${CABAL} v2-haddock -w ${HC} ${TEST} ${BENCH} all | color_cabal_output
 
-# REGENDATA ["-o",".travis.yml","--ghc-head","--irc-channel=irc.freenode.org#haskell-lens","--no-no-tests-no-bench","--no-unconstrained","cabal.project","--hlint","--hlint-options=--cpp-define=HLINT","--allow-failure=7.0.4","--allow-failure=7.2.2"]
+# REGENDATA ["--output=.travis.yml","--config=cabal.haskell-ci","cabal.project"]
 # EOF
diff --git a/CHANGELOG.markdown b/CHANGELOG.markdown
--- a/CHANGELOG.markdown
+++ b/CHANGELOG.markdown
@@ -1,3 +1,8 @@
+0.12.10 [2019.05.02]
+--------------------
+* Make the `parsec` and `attoparsec` dependencies optional with the use of
+  `Cabal` flags of the same names.
+
 0.12.9 [2018.07.04]
 -------------------
 * Add instances for the `Get` type from `binary`.
diff --git a/parsers.cabal b/parsers.cabal
--- a/parsers.cabal
+++ b/parsers.cabal
@@ -1,6 +1,6 @@
 name:          parsers
 category:      Text, Parsing
-version:       0.12.9
+version:       0.12.10
 license:       BSD3
 cabal-version: >= 1.10
 license-file:  LICENSE
@@ -26,8 +26,9 @@
              , GHC==7.10.3
              , GHC==8.0.2
              , GHC==8.2.2
-             , GHC==8.4.3
-             , GHC==8.6.1
+             , GHC==8.4.4
+             , GHC==8.6.5
+             , GHC==8.8.1
 
 extra-source-files:
   .travis.yml
@@ -44,6 +45,16 @@
   description:
     You can disable the use of the `binary` package using `-f-binary`.
 
+flag parsec
+  default: True
+  description:
+    You can disable the use of the `parsec` package using `-f-parsec`.
+
+flag attoparsec
+  default: True
+  description:
+    You can disable the use of the `attoparsec` package using `-f-attoparsec`.
+
 library
   default-language: Haskell2010
   exposed-modules:
@@ -61,6 +72,8 @@
   ghc-options: -Wall -fno-warn-wrong-do-bind -fwarn-monomorphism-restriction -fwarn-incomplete-record-updates
   if impl(ghc >= 7.2)
     ghc-options: -fwarn-identities -fwarn-incomplete-uni-patterns
+  if impl(ghc >= 7.10)
+    ghc-options: -fno-warn-trustworthy-safe
 
   build-depends:
     base                 >= 4.3      && < 5,
@@ -68,8 +81,6 @@
     charset              >= 0.3      && < 1,
     containers           >= 0.4      && < 0.7,
     semigroups           >= 0.12     && < 1,
-    parsec               >= 3.1      && < 3.2,
-    attoparsec           >= 0.12.1.4 && < 0.14,
     text                 >= 0.10     && < 1.3,
     transformers         >= 0.2      && < 0.6,
     mtl                  >= 2.0.1    && < 2.3,
@@ -77,19 +88,26 @@
     unordered-containers >= 0.2      && < 0.3
 
   if flag(binary)
-    build-depends: binary >= 0.7.2 && < 1
+    build-depends: binary     >= 0.7.2    && < 1
+  if flag(parsec)
+    build-depends: parsec     >= 3.1      && < 3.2
+  if flag(attoparsec)
+    build-depends: attoparsec >= 0.12.1.4 && < 0.14
 
 test-suite quickcheck
   type:    exitcode-stdio-1.0
   main-is: QuickCheck.hs
   default-language: Haskell2010
   build-depends:
-    attoparsec,
     base == 4.*,
     bytestring,
-    parsec >= 3,
     parsers,
     QuickCheck,
     quickcheck-instances
   ghc-options: -Wall -threaded
   hs-source-dirs: tests
+
+  if flag(parsec)
+    build-depends: parsec >= 3
+  if flag(attoparsec)
+    build-depends: attoparsec
diff --git a/src/Text/Parser/Char.hs b/src/Text/Parser/Char.hs
--- a/src/Text/Parser/Char.hs
+++ b/src/Text/Parser/Char.hs
@@ -69,10 +69,16 @@
 #endif
 import Data.Text
 import qualified Text.ParserCombinators.ReadP as ReadP
+import Text.Parser.Combinators
+
+#ifdef MIN_VERSION_parsec
 import qualified Text.Parsec as Parsec
+#endif
+
+#ifdef MIN_VERSION_attoparsec
 import qualified Data.Attoparsec.Types as Att
 import qualified Data.Attoparsec.Combinator as Att
-import Text.Parser.Combinators
+#endif
 
 -- | @oneOf cs@ succeeds if the current character is in the supplied
 -- list of characters @cs@. Returns the parsed character. See also
@@ -339,17 +345,21 @@
   text = lift . text
   {-# INLINE text #-}
 
+#ifdef MIN_VERSION_parsec
 instance Parsec.Stream s m Char => CharParsing (Parsec.ParsecT s u m) where
   satisfy   = Parsec.satisfy
   char      = Parsec.char
   notChar c = Parsec.satisfy (/= c)
   anyChar   = Parsec.anyChar
   string    = Parsec.string
+#endif
 
+#ifdef MIN_VERSION_attoparsec
 instance Att.Chunk t => CharParsing (Att.Parser t) where
   satisfy p = fmap e2c $ Att.satisfyElem $ p . e2c
     where e2c = Att.chunkElemToChar (undefined :: t)
   {-# INLINE satisfy #-}
+#endif
 
 instance CharParsing ReadP.ReadP where
   satisfy   = ReadP.satisfy
diff --git a/src/Text/Parser/Combinators.hs b/src/Text/Parser/Combinators.hs
--- a/src/Text/Parser/Combinators.hs
+++ b/src/Text/Parser/Combinators.hs
@@ -80,9 +80,16 @@
 #endif
 import Data.Traversable (sequenceA)
 #endif
+
+#ifdef MIN_VERSION_parsec
 import qualified Text.Parsec as Parsec
+#endif
+
+#ifdef MIN_VERSION_attoparsec
 import qualified Data.Attoparsec.Types as Att
 import qualified Data.Attoparsec.Combinator as Att
+#endif 
+
 import qualified Text.ParserCombinators.ReadP as ReadP
 
 #ifdef MIN_VERSION_binary
@@ -419,6 +426,7 @@
   notFollowedBy (IdentityT m) = IdentityT $ notFollowedBy m
   {-# INLINE notFollowedBy #-}
 
+#ifdef MIN_VERSION_parsec
 instance (Parsec.Stream s m t, Show t) => Parsing (Parsec.ParsecT s u m) where
   try           = Parsec.try
   (<?>)         = (Parsec.<?>)
@@ -427,7 +435,9 @@
   unexpected    = Parsec.unexpected
   eof           = Parsec.eof
   notFollowedBy = Parsec.notFollowedBy
+#endif
 
+#ifdef MIN_VERSION_attoparsec
 instance Att.Chunk t => Parsing (Att.Parser t) where
   try             = Att.try
   (<?>)           = (Att.<?>)
@@ -436,6 +446,7 @@
   unexpected      = fail
   eof             = Att.endOfInput
   notFollowedBy p = optional p >>= maybe (pure ()) (unexpected . show)
+#endif 
 
 #ifdef MIN_VERSION_binary
 instance Parsing B.Get where
diff --git a/src/Text/Parser/LookAhead.hs b/src/Text/Parser/LookAhead.hs
--- a/src/Text/Parser/LookAhead.hs
+++ b/src/Text/Parser/LookAhead.hs
@@ -36,15 +36,21 @@
 import Control.Monad.Trans.RWS.Strict as Strict
 import Control.Monad.Trans.Reader
 import Control.Monad.Trans.Identity
-import qualified Data.Attoparsec.Types as Att
-import qualified Data.Attoparsec.Combinator as Att
 #if __GLASGOW_HASKELL__ < 710
 import Data.Monoid
 #endif
 import qualified Text.ParserCombinators.ReadP as ReadP
-import qualified Text.Parsec as Parsec
 import Text.Parser.Combinators
 
+#ifdef MIN_VERSION_parsec
+import qualified Text.Parsec as Parsec
+#endif
+
+#ifdef MIN_VERSION_attoparsec
+import qualified Data.Attoparsec.Types as Att
+import qualified Data.Attoparsec.Combinator as Att
+#endif
+
 #ifdef MIN_VERSION_binary
 import qualified Data.Binary.Get as B
 #endif
@@ -86,11 +92,15 @@
   lookAhead = IdentityT . lookAhead . runIdentityT
   {-# INLINE lookAhead #-}
 
+#ifdef MIN_VERSION_parsec
 instance (Parsec.Stream s m t, Show t) => LookAheadParsing (Parsec.ParsecT s u m) where
   lookAhead = Parsec.lookAhead
+#endif
 
+#ifdef MIN_VERSION_attoparsec
 instance Att.Chunk i => LookAheadParsing (Att.Parser i) where
   lookAhead = Att.lookAhead
+#endif
 
 #ifdef MIN_VERSION_binary
 instance LookAheadParsing B.Get where
diff --git a/src/Text/Parser/Token.hs b/src/Text/Parser/Token.hs
--- a/src/Text/Parser/Token.hs
+++ b/src/Text/Parser/Token.hs
@@ -113,12 +113,18 @@
 import Data.Text hiding (empty,zip,foldl',take,map,length,splitAt,null,transpose)
 import Numeric (showIntAtBase)
 import qualified Text.ParserCombinators.ReadP as ReadP
-import qualified Text.Parsec as Parsec
-import qualified Data.Attoparsec.Types as Att
 import Text.Parser.Char
 import Text.Parser.Combinators
 import Text.Parser.Token.Highlight
 
+#ifdef MIN_VERSION_parsec
+import qualified Text.Parsec as Parsec
+#endif
+
+#ifdef MIN_VERSION_attoparsec
+import qualified Data.Attoparsec.Types as Att
+#endif
+
 -- | Skip zero or more bytes worth of white space. More complex parsers are
 -- free to consider comments as white space.
 whiteSpace :: TokenParsing m => m ()
@@ -925,8 +931,12 @@
   highlight h (Unlined m) = Unlined (highlight h m)
   {-# INLINE highlight #-}
 
+#ifdef MIN_VERSION_parsec
 instance Parsec.Stream s m Char => TokenParsing (Parsec.ParsecT s u m)
+#endif
 
+#ifdef MIN_VERSION_attoparsec
 instance Att.Chunk t => TokenParsing (Att.Parser t)
+#endif
 
 instance TokenParsing ReadP.ReadP
diff --git a/tests/QuickCheck.hs b/tests/QuickCheck.hs
--- a/tests/QuickCheck.hs
+++ b/tests/QuickCheck.hs
@@ -9,7 +9,9 @@
 
 import Control.Applicative
 
+#ifdef MIN_VERSION_attoparsec
 import Data.Attoparsec.Text (parseOnly)
+#endif
 import Data.String
 
 #if MIN_VERSION_base(4,7,0)
@@ -19,7 +21,9 @@
 import Test.QuickCheck
 import Test.QuickCheck.Instances ()
 
+#ifdef MIN_VERSION_parsec
 import Text.Parsec.Prim as P (parse)
+#endif
 import Text.Parser.Char
 import Text.Parser.Combinators
 import Text.ParserCombinators.ReadP (readP_to_S)
@@ -38,15 +42,31 @@
 
 instance Show (TestParser a) where show (TestParser n _) = n
 
-pAtto, pParsec, pReadP :: TestParser a
+#ifdef MIN_VERSION_attoparsec
+pAtto :: TestParser a
 pAtto = TestParser "attoparsec" $ \(P p) -> parseOnly p . fromString
+#endif
+
+#ifdef MIN_VERSION_parsec
+pParsec :: TestParser a
 pParsec = TestParser "parsec" $ \(P p) -> either (Left . show) Right . parse p "test input"
+#endif
+
+pReadP :: TestParser a
 pReadP = TestParser "ReadP" $ \(P p) s -> case readP_to_S p s of
   [] -> Left "parseFailed"
   (a,_):_ -> Right a
 
 instance Arbitrary (TestParser a) where
-    arbitrary = elements [pReadP, pAtto, pParsec]
+    arbitrary = elements ps
+        where
+            ps = [pReadP]
+#ifdef MIN_VERSION_attoparsec
+              ++ [pAtto]
+#endif
+#ifdef MIN_VERSION_parsec
+              ++ [pParsec]
+#endif
 
 -- -------------------------------------------------------------------------- --
 -- Main