diff --git a/.gitignore b/.gitignore
--- a/.gitignore
+++ b/.gitignore
@@ -7,12 +7,16 @@
 .DS_Store
 .gdb_history
 TAGS
-# Object files
+# Object files, etc
 *.a
 *.o
 *.so
 *.hi
 *.p_hi
+*.chi
+*.chs.h
+*.tix
+.hpc
 a.out
 # autotool
 autom4te.cache
@@ -22,7 +26,8 @@
 Main
 dist/
 cabal-dev/
+.cabal-sandbox/
 cabal.sandbox.config
-.cabal-sandbox
-.stack-work/
-stack.yaml
+dist-newstyle/
+.ghc.environment.*
+.stack-work
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
--- a/.travis.yml
+++ /dev/null
@@ -1,147 +0,0 @@
-# This Travis job script has been generated by a script via
-#
-#   haskell-ci 'twitter-conduit.cabal' '-o' '.travis.yml'
-#
-# For more information, see https://github.com/haskell-CI/haskell-ci
-#
-# version: 0.3.20190521
-#
-language: c
-dist: xenial
-git:
-  # whether to recursively clone submodules
-  submodules: false
-cache:
-  directories:
-    - $HOME/.cabal/packages
-    - $HOME/.cabal/store
-before_cache:
-  - rm -fv $CABALHOME/packages/hackage.haskell.org/build-reports.log
-  # remove files that are regenerated by 'cabal update'
-  - 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 $CABALHOME/packages/head.hackage
-matrix:
-  include:
-    - compiler: ghc-8.6.5
-      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.6.5","cabal-install-2.4"]}}
-    - compiler: ghc-8.4.4
-      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.4.4","cabal-install-2.4"]}}
-    - compiler: ghc-8.2.2
-      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.2.2","cabal-install-2.4"]}}
-    - compiler: ghc-8.0.2
-      addons: {"apt":{"sources":["hvr-ghc"],"packages":["ghc-8.0.2","cabal-install-2.4"]}}
-before_install:
-  - HC=$(echo "/opt/$CC/bin/ghc" | sed 's/-/\//')
-  - HCPKG="$HC-pkg"
-  - unset CC
-  - 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:
-  - ${CABAL} --version
-  - echo "$(${HC} --version) [$(${HC} --print-project-git-commit-id 2> /dev/null || echo '?')]"
-  - TEST=--enable-tests
-  - BENCH=--enable-benchmarks
-  - GHCHEAD=${GHCHEAD-false}
-  - 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
-  - cat $CABALHOME/config
-  - rm -fv cabal.project cabal.project.local cabal.project.freeze
-  - travis_retry ${CABAL} v2-update -v
-  # 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 -- '^(twitter-conduit)$' || true) | sed 's/^/constraints: /' | sed 's/$/ installed/' >> cabal.project.local; done"
-  - cat cabal.project || true
-  - cat cabal.project.local || true
-  - if [ -f "./configure.ac" ]; then (cd "." && autoreconf -i); fi
-  - ${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
-  - ${CABAL} v2-build -w ${HC} --disable-tests --disable-benchmarks --dep -j2 all | color_cabal_output
-script:
-  - DISTDIR=$(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 '{}' \;
-  # Generate cabal.project
-  - rm -rf cabal.project cabal.project.local cabal.project.freeze
-  - touch cabal.project
-  - |
-    echo 'packages: "twitter-conduit-*/*.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 -- '^(twitter-conduit)$' || true) | sed 's/^/constraints: /' | sed 's/$/ installed/' >> cabal.project.local; done"
-  - cat cabal.project || true
-  - cat cabal.project.local || true
-  # Building...
-  # this builds all libraries and executables (without tests/benchmarks)
-  - ${CABAL} v2-build -w ${HC} --disable-tests --disable-benchmarks all | color_cabal_output
-  # Building with tests and benchmarks...
-  # build & run tests, build benchmarks
-  - ${CABAL} v2-build -w ${HC} ${TEST} ${BENCH} all | color_cabal_output
-  # Testing...
-  - ${CABAL} v2-test -w ${HC} ${TEST} ${BENCH} all | color_cabal_output
-  # cabal check...
-  - (cd twitter-conduit-* && ${CABAL} -vnormal check)
-  # haddock...
-  - ${CABAL} v2-haddock -w ${HC} ${TEST} ${BENCH} all | color_cabal_output
-  # Building without installed constraints for packages in global-db...
-  - rm -f cabal.project.local
-  - ${CABAL} v2-build -w ${HC} --disable-tests --disable-benchmarks all | color_cabal_output
-
-# REGENDATA ["twitter-conduit.cabal","-o",".travis.yml"]
-# EOF
-
-notifications:
-  slack:
-    secure: HUt3eZH5IBJXlgH1/ob+iMqaQRSloqT3VY0rMLmD7gOMpUFm3a5/XYejqD+hd7EYQRa/Z1YCpmIBe3RYGPt6TnNGvIFdcJFFO7lOs7Ooxp03yB5kAMw9eACv/FNJPd2aIjYdKGbSab4XY4s9wW0GewYv0FHrNFWj81Rhl8C4fGg=
diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,7 @@
+## 0.5.1
+
+* Add result_type to searchTweets [#78](https://github.com/himura/twitter-conduit/pull/78).
+
 ## 0.5.0
 
 * Support for OverloadedLabels
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -1,6 +1,7 @@
 # twitter-conduit: An Conduit based Twitter API library for Haskell #
 
-[![Travis](https://img.shields.io/travis/himura/twitter-conduit/master.svg)](https://travis-ci.org/himura/twitter-conduit)
+![CI](https://github.com/himura/twitter-conduit/workflows/CI/badge.svg)
+[![Hackage](https://img.shields.io/hackage/v/twitter-conduit.svg?style=flat)](https://hackage.haskell.org/package/twitter-conduit)
 [![Hackage-Deps](https://img.shields.io/hackage-deps/v/twitter-conduit.svg)](http://packdeps.haskellers.com/feed?needle=twitter-conduit)
 
 ## About ##
diff --git a/Web/Twitter/Conduit/Api.hs b/Web/Twitter/Conduit/Api.hs
--- a/Web/Twitter/Conduit/Api.hs
+++ b/Web/Twitter/Conduit/Api.hs
@@ -193,6 +193,7 @@
 type SearchTweets = '[
       "lang" ':= T.Text
     , "locale" ':= T.Text
+    , "result_type" ':= T.Text
     , "count" ':= Integer
     , "until" ':= Day
     , "since_id" ':= Integer
diff --git a/Web/Twitter/Conduit/Response.hs b/Web/Twitter/Conduit/Response.hs
--- a/Web/Twitter/Conduit/Response.hs
+++ b/Web/Twitter/Conduit/Response.hs
@@ -1,6 +1,4 @@
 {-# LANGUAGE DeriveDataTypeable #-}
-{-# LANGUAGE DeriveFoldable #-}
-{-# LANGUAGE DeriveFunctor #-}
 {-# LANGUAGE DeriveTraversable #-}
 {-# LANGUAGE OverloadedStrings #-}
 
diff --git a/twitter-conduit.cabal b/twitter-conduit.cabal
--- a/twitter-conduit.cabal
+++ b/twitter-conduit.cabal
@@ -1,5 +1,5 @@
 name:              twitter-conduit
-version:           0.5.0
+version:           0.5.1
 license:           BSD3
 license-file:      LICENSE
 author:            HATTORI Hiroki, Hideyuki Tanaka, Takahiro HIMURA
@@ -11,7 +11,7 @@
 build-type:        Custom
 homepage:          https://github.com/himura/twitter-conduit
 
-tested-with:       GHC == 8.0.2, GHC == 8.2.2, GHC == 8.4.4, GHC == 8.6.5
+tested-with:       GHC == 8.4.4, GHC == 8.6.5, GHC == 8.8.3
 
 description:
   This package provides bindings to Twitter's APIs (see <https://dev.twitter.com/>).
@@ -25,7 +25,6 @@
 
 extra-source-files:
   .gitignore
-  .travis.yml
   README.md
   ChangeLog.md
   Warning.hs
