diff --git a/.travis.yml b/.travis.yml
new file mode 100644
index 0000000..4cc705a
--- /dev/null
+++ b/.travis.yml
@@ -0,0 +1,72 @@
+# Copyright Lewis Baker 2017
+#
+# Distributed under MIT license.
+# See LICENSE.txt file for details.
+
+language: cpp
+
+os: linux
+
+dist: trusty
+
+git:
+  submodules: true
+
+addons:
+  apt:
+    sources:
+    - ubuntu-toolchain-r-test
+    - llvm-toolchain-trusty
+    packages:
+    - python2.7
+    - clang-6.0
+    - lld-6.0
+    - ninja-build
+
+cache:
+  directories:
+  - ${TOOLS_DIR}/cmake-${CMAKE_VERSION}
+    
+compiler:
+- clang
+    
+env:
+  global:
+  - TOOLS_DIR=${TRAVIS_BUILD_DIR}/tools
+  - LLVM_INSTALL_PREFIX=${TOOLS_DIR}/llvm
+  - CMAKE_VERSION="3.9.1"
+matrix:
+  include:
+  - env: RELEASE=debug ARCH=x64 CLANG_VERSION=6.0
+  - env: RELEASE=optimised ARCH=x64 CLANG_VERSION=6.0
+  allow_failures:
+  # Clang 6.0~svn320382 has a bug that causes optimised builds to fail.
+  # See https://bugs.llvm.org/show_bug.cgi?id=34897
+  - env: RELEASE=optimised ARCH=x64 CLANG_VERSION=6.0
+ 
+before_install:
+- export CC="$CC-$CLANG_VERSION"
+- export CXX="$CXX-$CLANG_VERSION"
+- |
+  if [ ! -f "${TOOLS_DIR}/cmake-${CMAKE_VERSION}/cached" ]; then
+    CMAKE_URL="https://cmake.org/files/v3.9/cmake-${CMAKE_VERSION}-Linux-x86_64.tar.gz"
+    mkdir -p "${TOOLS_DIR}/cmake-${CMAKE_VERSION}"
+    travis_retry wget --no-check-certificate --quiet -O - "${CMAKE_URL}" | tar --strip-components=1 -xz -C "${TOOLS_DIR}/cmake-${CMAKE_VERSION}"
+    touch "${TOOLS_DIR}/cmake-${CMAKE_VERSION}/cached"
+  else
+    echo "Using cached CMake version ${CMAKE_VERSION}"
+  fi
+  export PATH="${TOOLS_DIR}/cmake-${CMAKE_VERSION}/bin:$PATH"
+ 
+install:
+- ./build-libcxx.sh
+- export LD_LIBRARY_PATH="${LLVM_INSTALL_PREFIX}/lib"
+ 
+before_script:
+- source ./init.sh
+
+script:
+- cake architecture=$ARCH release=$RELEASE --clang-executable="$CC" --libcxx-install-prefix="${LLVM_INSTALL_PREFIX}"
+
+notifications:
+  email: false
diff --git a/README.md b/README.md
index 23c14b6..35734df 100644
--- a/README.md
+++ b/README.md
@@ -41,8 +41,8 @@ It has been open-sourced in the hope that others will find it useful and that th
 can provide feedback on it and ways to improve it.
 
 It requires a compiler that supports the coroutines TS:
-- Windows + Visual Studio 2017 ![Windows Build Status](https://ci.appveyor.com/api/projects/status/github/lewissbaker/cppcoro?branch=master&svg=true&passingText=master%20-%20OK&failingText=master%20-%20Failing&pendingText=master%20-%20Pending)
-- Linux + Clang 5.0/6.0 + libc++
+- Windows + Visual Studio 2017 [![Windows Build Status](https://ci.appveyor.com/api/projects/status/github/lewissbaker/cppcoro?branch=master&svg=true&passingText=master%20-%20OK&failingText=master%20-%20Failing&pendingText=master%20-%20Pending)](https://ci.appveyor.com/project/lewissbaker/cppcoro/branch/master)
+- Linux + Clang 5.0/6.0 + libc++ [![Build Status](https://travis-ci.org/lewissbaker/cppcoro.svg?branch=master)](https://travis-ci.org/lewissbaker/cppcoro)
 
 The Linux version is functional except for the `io_context` and file I/O related classes which have not yet been implemented for Linux (see issue [#15](https://github.com/lewissbaker/cppcoro/issues/15) for more info).
 
diff --git a/args.cake b/args.cake
index bf69b11..52b27eb 100644
--- a/args.cake
+++ b/args.cake
@@ -4,6 +4,7 @@
 # This file defines extra command-line args specific to the cppcoro project.
 ##############################################################################
 from cake.script import Script
+import cake.system
 
 parser = Script.getCurrent().engine.parser
 
@@ -16,3 +17,30 @@ parser.add_option(
   help="Create projects instead of building a variant.",
   default=False,
   )
+
+if cake.system.isLinux() or cake.system.isDarwin():
+  parser.add_option(
+      "--clang-install-prefix",
+      dest="clangInstallPrefix",
+      type="string",
+      metavar="PATH",
+      default=None,
+      help="Path where clang has been installed."
+      )
+
+  parser.add_option(
+    "--clang-executable",
+    dest="clangExecutable",
+    type="string",
+    metavar="FILE",
+    default="clang",
+    help="Name or full-path of clang executable to compile with")
+
+  parser.add_option(
+    "--libcxx-install-prefix",
+    dest="libcxxInstallPrefix",
+    type="string",
+    metavar="PATH",
+    default=None,
+    help="Path where libc++ has been installed.\n"
+         "Defaults to value of --clang-install-prefix")
diff --git a/build-clang.sh b/build-clang.sh
new file mode 100755
index 0000000..e652216
--- /dev/null
+++ b/build-clang.sh
@@ -0,0 +1,104 @@
+#!/bin/bash
+#
+# Builds Clang and LLD from source.
+
+export WORKSPACE_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+export LLVM_PROJECT="${WORKSPACE_ROOT}/tools/llvm-project"
+
+: "${LLVM_REPO:=https://github.com/llvm-mirror/llvm.git}"
+: "${LLVM_REF:=master}"
+
+: "${CLANG_REPO:=https://github.com/llvm-mirror/clang.git}"
+: "${CLANG_REF:=master}"
+
+: "${LLD_REPO:=https://github.com/llvm-mirror/lld.git}"
+: "${LLD_REF:=master}"
+
+: "${LIBCXX_REPO:=https://github.com/llvm-mirror/libcxx.git}"
+: "${LIBCXX_REF:=master}"
+
+: "${LLVM_INSTALL_PREFIX:=$WORKSPACE_ROOT/build/llvm-install}"
+
+: "${CXX:=clang++}"
+: "${CC:=clang}"
+
+if [ ! -d "${LLVM_PROJECT}" ]; then
+  mkdir -p "${LLVM_PROJECT}" || exit
+fi
+
+cd "${LLVM_PROJECT}" || exit
+
+if [ ! -d llvm/.git ]; then
+  git clone --depth=1 -b "$LLVM_REF" -- "$LLVM_REPO" llvm || exit
+else
+  (cd llvm &&
+   git remote set-url origin "$LLVM_REPO" &&
+   git fetch origin "$LLVM_REF" &&
+   git checkout FETCH_HEAD) || exit
+fi
+
+if [ ! -d llvm/tools/clang/.git ]; then
+  git clone --depth=1 -b "$CLANG_REF" -- "$CLANG_REPO" llvm/tools/clang || exit
+  ln -s llvm/tools/clang clang || exit
+else
+  (cd llvm/tools/clang &&
+   git remote set-url origin "$CLANG_REPO" &&
+   git fetch --depth=1 origin "$CLANG_REF" &&
+   git checkout FETCH_HEAD) || exit
+fi
+
+if [ ! -d llvm/tools/lld/.git ]; then
+  git clone --depth=1 -b "$LLD_REF" -- "$LLD_REPO" llvm/tools/lld || exit
+  ln -s llvm/tools/lld lld || exit
+else
+  (cd llvm/tools/lld &&
+   git remote set-url origin "$LLD_REPO" &&
+   git fetch --depth=1 origin "$LLD_REF" &&
+   git checkout FETCH_HEAD) || exit
+fi
+
+if [ ! -d llvm/projects/libcxx.git ]; then
+  git clone --depth=1 -b "$LIBCXX_REF" -- "$LIBCXX_REPO" llvm/projects/libcxx || exit
+  ln -s llvm/projects/libcxx libcxx || exit
+else
+  (cd llvm/projects/libcxx &&
+   git remote set-url origin "$LIBCXX_REPO" &&
+   git fetch --depth=1 origin "$LIBCXX_REF" &&
+   git checkout FETCH_HEAD) || exit
+fi
+
+cd "$WORKSPACE_ROOT" || exit
+
+if [ ! -d build/clang ]; then
+  mkdir -p build/clang || exit
+fi
+
+# Build clang toolchain
+(mkdir -p build/clang && \
+ cd build/clang && \
+ cmake -GNinja \
+       -DCMAKE_CXX_COMPILER="$CXX" \
+       -DCMAKE_C_COMPILER="$CC" \
+       -DCMAKE_BUILD_TYPE=MinSizeRel \
+       -DCMAKE_INSTALL_PREFIX="${LLVM_INSTALL_PREFIX}" \
+       -DCMAKE_BUILD_WITH_INSTALL_RPATH="yes" \
+       -DLLVM_TARGETS_TO_BUILD=X86 \
+       -DLLVM_ENABLE_PROJECTS="lld;clang" \
+       "${LLVM_PROJECT}/llvm" && \
+  ninja install-clang \
+        install-clang-headers \
+        install-llvm-ar \
+        install-lld) || exit
+
+# Build libcxx using clang we just built
+(mkdir -p build/libcxx && \
+ cd build/libcxx && \
+ cmake -GNinja \
+       -DCMAKE_CXX_COMPILER="${LLVM_INSTALL_PREFIX}/bin/clang++" \
+       -DCMAKE_C_COMPILER="${LLVM_INSTALL_PREFIX}/bin/clang" \
+       -DCMAKE_BUILD_TYPE=Release \
+       -DCMAKE_INSTALL_PREFIX="${LLVM_INSTALL_PREFIX}" \
+       -DLLVM_PATH="${LLVM_PROJECT}/llvm" \
+       -DLIBCXX_CXX_ABI=libstdc++ \
+       "${LLVM_PROJECT}/libcxx" && \
+  ninja install) || exit
diff --git a/build-libcxx.sh b/build-libcxx.sh
new file mode 100755
index 0000000..08e7f81
--- /dev/null
+++ b/build-libcxx.sh
@@ -0,0 +1,56 @@
+#!/bin/bash
+#
+# Builds libc++ from source
+
+export WORKSPACE_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+export LLVM_PROJECT="${WORKSPACE_ROOT}/tools/llvm-project"
+
+: "${LLVM_REPO:=https://github.com/llvm-mirror/llvm.git}"
+: "${LLVM_REF:=master}"
+
+: "${LIBCXX_REPO:=https://github.com/llvm-mirror/libcxx.git}"
+: "${LIBCXX_REF:=master}"
+
+: "${LLVM_INSTALL_PREFIX:=$WORKSPACE_ROOT/build/llvm-install}"
+
+: "${CXX:=clang++}"
+: "${CC:=clang}"
+
+if [ ! -d "${LLVM_PROJECT}" ]; then
+  mkdir -p "${LLVM_PROJECT}" || exit
+fi
+
+cd "${LLVM_PROJECT}" || exit
+
+if [ ! -d llvm/.git ]; then
+  git clone --depth=1 -b "$LLVM_REF" -- "$LLVM_REPO" llvm || exit
+else
+  (cd llvm &&
+   git remote set-url origin "$LLVM_REPO" &&
+   git fetch origin "$LLVM_REF" &&
+   git checkout FETCH_HEAD) || exit
+fi
+
+if [ ! -d llvm/projects/libcxx.git ]; then
+  git clone --depth=1 -b "$LIBCXX_REF" -- "$LIBCXX_REPO" llvm/projects/libcxx || exit
+  ln -s llvm/projects/libcxx libcxx || exit
+else
+  (cd llvm/projects/libcxx &&
+   git remote set-url origin "$LIBCXX_REPO" &&
+   git fetch --depth=1 origin "$LIBCXX_REF" &&
+   git checkout FETCH_HEAD) || exit
+fi
+
+cd "$WORKSPACE_ROOT" || exit
+
+(mkdir -p build/libcxx && \
+ cd build/libcxx && \
+ cmake -GNinja \
+       -DCMAKE_CXX_COMPILER="${CXX}" \
+       -DCMAKE_C_COMPILER="${CC}" \
+       -DCMAKE_BUILD_TYPE=Release \
+       -DCMAKE_INSTALL_PREFIX="${LLVM_INSTALL_PREFIX}" \
+       -DLLVM_PATH="${LLVM_PROJECT}/llvm" \
+       -DLIBCXX_CXX_ABI=libstdc++ \
+       "${LLVM_PROJECT}/libcxx" && \
+  ninja install) || exit
diff --git a/config.cake b/config.cake
index 77b7103..969b036 100644
--- a/config.cake
+++ b/config.cake
@@ -176,45 +176,103 @@ if cake.system.isWindows() or cake.system.isCygwin():
     except CompilerNotFoundError, e:
       print str(e)
 
-elif cake.system.isLinux():
+elif cake.system.isLinux() or cake.system.isDarwin():
 
+  def firstExisting(paths, default=None):
+    for p in paths:
+      if os.path.exists(p):
+        return p
+    else:
+      return default
+
+      
+      
+  if cake.system.isLinux():
+    defaultInstallPaths = ["/usr"]
+  elif cake.system.isDarwin():
+    defaultInstallPaths = ["/usr/local/opt/llvm", "/usr"]
+      
+  clangInstallPrefix = engine.options.clangInstallPrefix
+  clangExe = engine.options.clangExecutable
+  
+  if clangInstallPrefix is None:
+    # If no clang install prefix was specified then try to deduce it
+    # from the --clang-executable path.
+    if os.path.isabs(clangExe):
+      clangBinPath = cake.path.dirName(clangExe)
+      if cake.path.baseName(clangBinPath) == 'bin':
+        clangInstallPrefix = cake.path.dirName(clangBinPath)
+
+    # Use sensible system defaults if neither --clang-executable or
+    # --clang-install-prefix command-line arguments are specified.
+    if clangInstallPrefix is None:
+      clangInstallPrefix = firstExisting(defaultInstallPaths, default="/usr")
+
+  libcxxInstallPrefix = engine.options.libcxxInstallPrefix
+  if libcxxInstallPrefix is None:
+    libcxxInstallPrefix = clangInstallPrefix
+
+  # If the user didn't specify an absolute path to clang then look for it in
+  # the installed clang bin directory.
+  if not os.path.isabs(clangExe):
+    clangExe = cake.path.join(clangInstallPrefix, 'bin', clangExe)
+
+  # Extract the clang version suffix from the file-name
+  # We'll try and use other LLVM tools with the same suffix if they exist.
+  clangName = cake.path.baseName(clangExe)
+  versionSuffix = clangName[5:] if clangName.startswith('clang-') else ""
+
+  clangExeDir = cake.path.dirName(clangExe)
+  clangBinPath = cake.path.join(clangInstallPrefix, 'bin')
+
+  binPaths = [clangExeDir]
+  if clangBinPath not in binPaths:
+    binPaths.append(clangBinPath)
+
+  llvmArExe = firstExisting(
+    cake.path.join(binPaths, ['llvm-ar' + versionSuffix, 'llvm-ar', 'ar']),
+    default="/usr/bin/ar")
+
+  # Prefer lld if available, otherwise fall back to system ld
+  lldExe = firstExisting(
+    cake.path.join(binPaths, ['ld.lld' + versionSuffix, 'ld.lld']),
+    )
+    
+  engine.logger.outputInfo(
+    "clang: " + clangExe + "\n" +
+    "llvm-ar: " + llvmArExe + "\n")
+    
   from cake.library.compilers.clang import ClangCompiler
 
+  if cake.system.isLinux():
+    platform = 'linux'
+  elif cake.system.isDarwin():
+    platform = 'darwin'
+  
   clangVariant = baseVariant.clone(compiler='clang',
-                                   platform='linux',
+                                   platform=platform,
                                    architecture='x64')
 
-  # If you have built your own version of Clang, you can modify
-  # this variable to point to the CMAKE_INSTALL_PREFIX for
-  # where you have installed your clang/libcxx build.
-  clangInstallPrefix = '/usr'
-
-  # Set this to the install-prefix of where libc++ is installed.
-  # You only need to set this if it is not installed at the same
-  # location as clangInstallPrefix.
-  libCxxInstallPrefix = None # '/path/to/install'
-
-  clangBinPath = cake.path.join(clangInstallPrefix, 'bin')
-
   compiler = ClangCompiler(
     configuration=configuration,
-    clangExe=cake.path.join(clangBinPath, 'clang'),
-    llvmArExe=cake.path.join(clangBinPath, 'llvm-ar'),
+    clangExe=clangExe,
+    llvmArExe=llvmArExe,
     binPaths=[clangBinPath])
 
   compiler.addCppFlag('-std=c++1z')
   compiler.addCppFlag('-fcoroutines-ts')
   compiler.addCppFlag('-m64')
 
-  compiler.addModuleFlag('-fuse-ld=lld')
-  compiler.addProgramFlag('-fuse-ld=lld')
+  if lldExe:
+    compiler.addModuleFlag('-fuse-ld=' + lldExe)
+    compiler.addProgramFlag('-fuse-ld=' + lldExe)
   
-  if libCxxInstallPrefix:
+  if libcxxInstallPrefix != clangInstallPrefix:
     compiler.addCppFlag('-nostdinc++')
     compiler.addIncludePath(cake.path.join(
-      libCxxInstallPrefix, 'include', 'c++', 'v1'))
+      libcxxInstallPrefix, 'include', 'c++', 'v1'))
     compiler.addLibraryPath(cake.path.join(
-      libCxxInstallPrefix, 'lib'))
+      libcxxInstallPrefix, 'lib'))
   else:
     compiler.addCppFlag('-stdlib=libc++')
 
@@ -229,8 +287,8 @@ elif cake.system.isLinux():
 
   env = clangVariant.tools["env"]
   env["COMPILER"] = "clang"
-  env["COMPILER_VERSION"] = "5.0"
-  env["PLATFORM"] = "linux"
+  env["COMPILER_VERSION"] = compiler.version
+  env["PLATFORM"] = platform
   env["ARCHITECTURE"] = "x64"
 
   clangDebugVariant = clangVariant.clone(release='debug')
@@ -250,86 +308,11 @@ elif cake.system.isLinux():
   compiler = clangOptimisedVariant.tools["compiler"]
   compiler.addCppFlag('-O3')
   compiler.addCppFlag('-g')
-  compiler.addCppFlag('-flto')
-  compiler.addProgramFlag('-flto')
-  compiler.addModuleFlag('-flto')
-
-  configuration.addVariant(clangOptimisedVariant)
-
-elif cake.system.isDarwin():
-
-  from cake.library.compilers.clang import ClangCompiler
-
-  clangVariant = baseVariant.clone(compiler='clang',
-                                   platform='darwin',
-                                   architecture='x86_64')
-
-  # If you have built your own version of Clang, you can modify
-  # this variable to point to the CMAKE_INSTALL_PREFIX for
-  # where you have installed your clang/libcxx build.
-  clangInstallPrefix = '/usr/local/opt/llvm'
-
-  # Set this to the install-prefix of where libc++ is installed.
-  # You only need to set this if it is not installed at the same
-  # location as clangInstallPrefix.
-  libCxxInstallPrefix = None # '/path/to/install'
-
-  clangBinPath = cake.path.join(clangInstallPrefix, 'bin')
-
-  compiler = ClangCompiler(
-    configuration=configuration,
-    clangExe=cake.path.join(clangBinPath, 'clang'),
-    llvmArExe=cake.path.join(clangBinPath, 'llvm-ar'),
-    binPaths=[clangBinPath])
-
-  compiler.addCppFlag('-std=c++17')
-  compiler.addCppFlag('-fcoroutines-ts')
-  compiler.addCppFlag('-m64')
-
-  compiler.addModuleFlag('-fuse-ld=/usr/bin/ld')
-  compiler.addProgramFlag('-fuse-ld=/usr/bin/ld')
-
-  if libCxxInstallPrefix:
-    compiler.addCppFlag('-nostdinc++')
-    compiler.addIncludePath(cake.path.join(
-      libCxxInstallPrefix, 'include', 'c++', 'v1'))
-    compiler.addLibraryPath(cake.path.join(
-      libCxxInstallPrefix, 'lib'))
-  else:
-    compiler.addCppFlag('-stdlib=libc++')
-
-  compiler.addLibrary('c++')
-
-  #compiler.addProgramFlag('-Wl,--trace')
-  #compiler.addProgramFlag('-Wl,-v')
-
-  clangVariant.tools['compiler'] = compiler
-
-  env = clangVariant.tools["env"]
-  env["COMPILER"] = "clang"
-  env["COMPILER_VERSION"] = "5.0"
-  env["PLATFORM"] = "darwin"
-  env["ARCHITECTURE"] = "x86_64"
-
-  clangDebugVariant = clangVariant.clone(release='debug')
-  clangDebugVariant.tools["env"]["RELEASE"] = 'debug'
-
-  # Configure debug-specific settings here
-  compiler = clangDebugVariant.tools["compiler"]
-  compiler.addCppFlag('-O0')
-  compiler.addCppFlag('-g')
-
-  configuration.addVariant(clangDebugVariant)
-
-  clangOptimisedVariant = clangVariant.clone(release='optimised')
-  clangOptimisedVariant.tools["env"]["RELEASE"] = 'optimised'
-
-  # Configure optimised-specific settings here
-  compiler = clangOptimisedVariant.tools["compiler"]
-  compiler.addCppFlag('-O3')
-  compiler.addCppFlag('-g')
-  compiler.addCppFlag('-flto')
-  compiler.addProgramFlag('-flto')
-  compiler.addModuleFlag('-flto')
+  
+  # Only use link-time optimisation if we're using LLD
+  if lldExe:
+    compiler.addCppFlag('-flto')
+    compiler.addProgramFlag('-flto')
+    compiler.addModuleFlag('-flto')
 
   configuration.addVariant(clangOptimisedVariant)
diff --git a/init.sh b/init.sh
old mode 100644
new mode 100755
diff --git a/tools/cake b/tools/cake
index 88d8c43..db43f33 160000
--- a/tools/cake
+++ b/tools/cake
@@ -1 +1 @@
-Subproject commit 88d8c43e9ec2e49adc89e671c849b0b1f5814e4d
+Subproject commit db43f336b95d367163b967491f4e22d252ae59b4