diff --git a/.travis.yml b/.travis.yml
index 0f25e72f..70c04572 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,48 +2,50 @@ language: c
 
 matrix:
   include:
-    - env: JOB=toxcore ENV=osx RUN_TESTS=true
-      os: osx
-    - env: JOB=hstox ENV=linux
-      language: haskell
-      ghc: 7.8
-    - env: JOB=autotools ENV=linux
-      compiler: gcc
-    - env: JOB=toxcore ENV=linux
-      compiler: clang
-    - env: JOB=toxcore ENV=windows ARCH=i686
-      services:
-        - docker
-    - env: JOB=toxcore ENV=windows ARCH=x86_64
-      services:
-        - docker
+  - env: JOB=toxcore ENV=osx RUN_TESTS=true
+    os: osx
+  - env: JOB=autotools ENV=linux
+    compiler: gcc
+  - env: JOB=toxcore ENV=linux
+    compiler: clang
+  - env: JOB=toxcore ENV=windows ARCH=i686
+    services:
+    - docker
+  - env: JOB=toxcore ENV=windows ARCH=x86_64
+    services:
+    - docker
   fast_finish: true
 
 addons:
   apt:
     sources:
-      - avsm
+    - avsm
+    - hvr-ghc
     packages:
-      - check
-      - libcv-dev             # For av_test.
-      - libhighgui-dev        # For av_test.
-      - libopencv-contrib-dev # For av_test.
-      - libsndfile1-dev       # For av_test.
-      - libvpx-dev
-      - opam                  # For apidsl and Frama-C.
-      - portaudio19-dev       # For av_test.
-      - texinfo               # For libconfig.
+    - alex-3.1.7            # For hstox.
+    - cabal-install-1.18    # For hstox.
+    - check                 # For tests.
+    - ghc-7.8.4             # For hstox.
+    - happy-1.19.5          # For hstox.
+    - libcv-dev             # For av_test.
+    - libhighgui-dev        # For av_test.
+    - libopencv-contrib-dev # For av_test.
+    - libsndfile1-dev       # For av_test.
+    - libvpx-dev            # For toxav.
+    - opam                  # For apidsl and Frama-C.
+    - portaudio19-dev       # For av_test.
+    - texinfo               # For libconfig.
 
 cache:
   directories:
-    # Although Travis documentation says not to rely on the value of $HOME, we
-    # rely on it here because cabal installs its packages there by default. If
-    # that ever changes, these values need to be updated.
-    # Note that we can't use shell expressions in these paths, so we can't ask
-    # cabal where its data is stored.
-    - $HOME/.cabal
-    - $HOME/.ghc
-    - $HOME/cache
+  # Although Travis documentation says not to rely on the value of $HOME, we
+  # rely on it here because cabal installs its packages there by default. If
+  # that ever changes, these values need to be updated.
+  # Note that we can't use shell expressions in these paths, so we can't ask
+  # cabal where its data is stored.
+  - $HOME/.cabal
+  - $HOME/.ghc
+  - $HOME/cache
 
 install:       other/travis/phase $JOB $ENV install
 script:        other/travis/phase $JOB $ENV script
@@ -53,12 +55,11 @@ after_failure: other/travis/phase $JOB $ENV after_failure
 notifications:
   irc:
     channels:
-      - "chat.freenode.net#toktok-status"
+    - "chat.freenode.net#toktok-status"
     template:
-      - "%{result} %{repository_name} %{build_url}"
-      - "#%{build_number} changes: %{compare_url}"
-
+    - "%{result} %{repository_name} %{build_url}"
+    - "#%{build_number} changes: %{compare_url}"
 
 branches:
   only:
-    - master
+  - master
diff --git a/other/travis/env-linux.sh b/other/travis/env-linux.sh
index fca8a412..4615016e 100644
--- a/other/travis/env-linux.sh
+++ b/other/travis/env-linux.sh
@@ -1,5 +1,8 @@
 #!/bin/sh
 
+export PATH=/opt/ghc/7.8.4/bin:/opt/cabal/1.18/bin:/opt/alex/3.1.7/bin:/opt/happy/1.19.5/bin:$PATH
+export PATH=$HOME/.cabal/bin:$PATH
+
 CMAKE=cmake
 CMAKE_EXTRA_FLAGS="$CMAKE_EXTRA_FLAGS -DFORMAT_TEST=ON"
 NPROC=`nproc`
diff --git a/other/travis/hstox-install b/other/travis/hstox-install
deleted file mode 100755
index 773bf388..00000000
--- a/other/travis/hstox-install
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/bin/sh
-
-# An initial update is required or the cabal cache will be empty and no packages
-# can be installed.
-cabal update
-
-# We need to install happy explicitly, otherwise setup-Simple-Cabal will fail to
-# install.
-cabal install happy
-
-# Fetch hstox and msgpack-c.
-git clone --recursive --depth=1 https://github.com/TokTok/hs-toxcore ../hs-toxcore
-git clone --depth=1 https://github.com/msgpack/msgpack-c testing/hstox/msgpack-c
-
-# Install toxcore dependencies before hstox, as hstox needs libsodium.
-. other/travis/toxcore-linux-install
-
-# Install the hstox test runner.
-CABAL_FLAGS="--disable-library-profiling"
-CABAL_FLAGS="$CABAL_FLAGS --extra-include-dirs=$CACHE_DIR/include"
-CABAL_FLAGS="$CABAL_FLAGS --extra-lib-dirs=$CACHE_DIR/lib"
-(cd ../hs-toxcore && cabal install $CABAL_FLAGS)
diff --git a/other/travis/hstox-script b/other/travis/hstox-script
deleted file mode 100755
index a75c477b..00000000
--- a/other/travis/hstox-script
+++ /dev/null
@@ -1,3 +0,0 @@
-#!/bin/sh
-
-make -C testing/hstox check
diff --git a/other/travis/toxcore-linux-install b/other/travis/toxcore-linux-install
index d1acadce..59bf1048 100755
--- a/other/travis/toxcore-linux-install
+++ b/other/travis/toxcore-linux-install
@@ -36,6 +36,30 @@ sed -i -e '/^import sys$/a import urllib3.contrib.pyopenssl\nurllib3.contrib.pyo
   cd - # popd
 }
 
+# Install msgpack-c.
+[ -f $CACHE_DIR/lib/libmsgpackc.so ] || {
+  git clone --depth=1 https://github.com/msgpack/msgpack-c ../msgpack-c
+  $CC -shared -fPIC -O3 -I../msgpack-c/include ../msgpack-c/src/*.c -o $CACHE_DIR/lib/libmsgpackc.so
+  cp -a ../msgpack-c/include/* $CACHE_DIR/include/
+  sed -e "s|@prefix@|$CACHE_DIR|"            \
+      -e 's|@exec_prefix@|${prefix}|'        \
+      -e 's|@libdir@|${prefix}/lib|'         \
+      -e 's|@includedir@|${prefix}/include|' \
+      -e 's|@VERSION@|2.1.1|'                \
+      ../msgpack-c/msgpack.pc.in             \
+      > $CACHE_DIR/lib/pkgconfig/msgpack.pc
+  # TODO(iphydf): This doesn't work, because the cmake version on travis is too
+  # old. We're building it manually, instead.
+  # cd ../msgpack-c # pushd
+  # cmake . -DCMAKE_INSTALL_PREFIX:PATH=$CACHE_DIR \
+  #   -DMSGPACK_ENABLE_CXX=OFF                     \
+  #   -DMSGPACK_BUILD_EXAMPLES=OFF                 \
+  #   -DMSGPACK_BUILD_TESTS=OFF
+  # make -j$NPROC
+  # make install -j$NPROC
+  # cd - # popd
+}
+
 # Install libconfig (version in ubuntu-precise too old).
 [ -f $CACHE_DIR/lib/libconfig.a ] || {
   git clone --depth=1 --branch=REL1_6_STABLE https://github.com/hyperrealm/libconfig ../libconfig
@@ -56,3 +80,16 @@ sed -i -e '/^import sys$/a import urllib3.contrib.pyopenssl\nurllib3.contrib.pyo
   make install -j$NPROC
   cd - # popd
 }
+
+if [ "$CC" = "clang" ]; then
+  # An initial update is required or the cabal cache will be empty and no packages
+  # can be installed.
+  cabal update
+
+  # Install the hstox test runner after installing libsodium.
+  CABAL_FLAGS="--disable-library-profiling"
+  CABAL_FLAGS="$CABAL_FLAGS --extra-include-dirs=$CACHE_DIR/include"
+  CABAL_FLAGS="$CABAL_FLAGS --extra-lib-dirs=$CACHE_DIR/lib"
+  git clone --recursive --depth=1 https://github.com/TokTok/hs-toxcore ../hs-toxcore
+  (cd ../hs-toxcore && cabal install $CABAL_FLAGS)
+fi