diff --git a/.travis.yml b/.travis.yml
index 55e9319f2..4b6736a00 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -13,26 +13,26 @@ install:
  - if [ "$CXX" = "clang++" ] && [ "$TRAVIS_OS_NAME" == "linux" ]; then export CXX="clang++-5.0" CC="clang-5.0"; fi
 # boost
  - wget https://dl.bintray.com/boostorg/release/1.66.0/source/boost_1_66_0.zip && unzip -q boost_1_66_0.zip && cd boost_1_66_0 && ./bootstrap.sh && ./b2 -j3 --prefix=${BASE}/usr --with-timer --with-chrono --with-test address-model=64 install > /dev/null && cd ..
- - if [ "$TRAVIS_OS_NAME" == "linux" ]; then wget https://www.openssl.org/source/openssl-1.1.0h.tar.gz && tar xf openssl-1.1.0h.tar.gz && cd openssl-1.1.0h && ./config --prefix=${BASE}/usr && make && make install > /dev/null && cd ..; fi
- - if [ "$TRAVIS_OS_NAME" == "osx" ]; then wget https://www.openssl.org/source/openssl-1.1.0h.tar.gz && tar xf openssl-1.1.0h.tar.gz && cd openssl-1.1.0h && ./Configure darwin64-x86_64-cc --prefix=${BASE}/usr && make && make install > /dev/null && cd ..; fi
+ - if [ "$TRAVIS_OS_NAME" == "linux" ]; then wget https://www.openssl.org/source/openssl-1.1.0h.tar.gz && tar xf openssl-1.1.0h.tar.gz && cd openssl-1.1.0h && ./config --prefix=${BASE}/usr && make -j2 && make install > /dev/null && cd ..; fi
+ - if [ "$TRAVIS_OS_NAME" == "osx" ]; then wget https://www.openssl.org/source/openssl-1.1.0h.tar.gz && tar xf openssl-1.1.0h.tar.gz && cd openssl-1.1.0h && ./Configure darwin64-x86_64-cc --prefix=${BASE}/usr && make -j2 && make install > /dev/null && cd ..; fi
 
 matrix:
   include:
     - os: osx
       compiler: clang
-      env: FLAGS="-DMQTT_NO_TLS=ON  -DMQTT_USE_WS=ON" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers"
+      env: FLAGS="-DMQTT_NO_TLS=ON  -DMQTT_USE_WS=ON" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers" MAKEFLAGS="-j2"
     - os: osx
       compiler: clang
-      env: FLAGS="-DMQTT_NO_TLS=ON  -DMQTT_USE_WS=OFF" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers"
+      env: FLAGS="-DMQTT_NO_TLS=ON  -DMQTT_USE_WS=OFF" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers" MAKEFLAGS="-j2"
     - os: osx
       compiler: clang
-      env: FLAGS="-DMQTT_NO_TLS=OFF -DMQTT_USE_WS=ON" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers"
+      env: FLAGS="-DMQTT_NO_TLS=OFF -DMQTT_USE_WS=ON" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers" MAKEFLAGS="-j2"
     - os: osx
       compiler: clang
-      env: FLAGS="-DMQTT_NO_TLS=OFF -DMQTT_USE_WS=OFF" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers"
+      env: FLAGS="-DMQTT_NO_TLS=OFF -DMQTT_USE_WS=OFF" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers" MAKEFLAGS="-j2"
     - os: linux
       compiler: clang
-      env: FLAGS="-DMQTT_NO_TLS=ON  -DMQTT_USE_WS=ON" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers"
+      env: FLAGS="-DMQTT_NO_TLS=ON  -DMQTT_USE_WS=ON" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers" MAKEFLAGS="-j2"
       addons:
         apt:
           sources:
@@ -50,7 +50,7 @@ matrix:
     - os: linux
       sudo: required
       compiler: clang
-      env: FLAGS="-DMQTT_NO_TLS=OFF  -DMQTT_USE_WS=ON" CFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers -fsanitize=address -fno-omit-frame-pointer" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers -fsanitize=address -fno-omit-frame-pointer" LDFLAGS="-Wno-ignored-qualifiers -fsanitize=address"
+      env: FLAGS="-DMQTT_NO_TLS=OFF  -DMQTT_USE_WS=ON" CFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers -fsanitize=address -fno-omit-frame-pointer" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers -fsanitize=address -fno-omit-frame-pointer" LDFLAGS="-Wno-ignored-qualifiers -fsanitize=address" MAKEFLAGS="-j2"
       addons:
         apt:
           sources:
@@ -67,7 +67,7 @@ matrix:
             - libc6-dbg
     - os: linux
       compiler: gcc
-      env: FLAGS="-DMQTT_NO_TLS=ON -DMQTT_USE_WS=OFF" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers"
+      env: FLAGS="-DMQTT_NO_TLS=ON -DMQTT_USE_WS=OFF" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers" MAKEFLAGS="-j2"
       addons:
         apt:
           sources:
@@ -81,7 +81,7 @@ matrix:
             - libc6-dbg
     - os: linux
       compiler: gcc
-      env: FLAGS="-DMQTT_NO_TLS=OFF -DMQTT_USE_WS=ON" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers"
+      env: FLAGS="-DMQTT_NO_TLS=OFF -DMQTT_USE_WS=ON" CXXFLAGS="-Werror -g -Wall -Wextra -Wno-ignored-qualifiers" MAKEFLAGS="-j1"
       addons:
         apt:
           sources:
@@ -95,4 +95,4 @@ matrix:
             - libc6-dbg
 
 script:
-  - mkdir build && cd build && cmake -DCMAKE_CXX_COMPILER="${CXX}" -DCMAKE_C_COMPILER="${CC}" -DCMAKE_LIBRARY_PATH="${BASE}/usr/lib" -DBOOST_ROOT="${BASE}/usr" -DOPENSSL_ROOT_DIR="${BASE}/usr" $FLAGS $CXXFLAGS $LDFLAGS .. && make VERBOSE=1 && ctest -VV
+  - mkdir build && cd build && cmake -DCMAKE_CXX_COMPILER="${CXX}" -DCMAKE_C_COMPILER="${CC}" -DCMAKE_LIBRARY_PATH="${BASE}/usr/lib" -DBOOST_ROOT="${BASE}/usr" -DOPENSSL_ROOT_DIR="${BASE}/usr" $FLAGS $CXXFLAGS $LDFLAGS .. && make $MAKEFLAGS VERBOSE=1 && ctest -VV
diff --git a/include/mqtt/endpoint.hpp b/include/mqtt/endpoint.hpp
index 2a999c548..60c89a9da 100644
--- a/include/mqtt/endpoint.hpp
+++ b/include/mqtt/endpoint.hpp
@@ -3839,12 +3839,25 @@ class endpoint : public std::enable_shared_from_this<endpoint<Socket, Mutex, Loc
      * @brief Apply f to stored messages.
      * @param f applying function. f should be void(char const*, std::size_t)
      */
-    template <typename F>
-    void for_each_store(F&& f) {
+    void for_each_store(std::function<void(char const*, std::size_t)> const& f) {
         LockGuard<Mutex> lck (store_mtx_);
         auto& idx = store_.template get<tag_seq>();
         for (auto const & e : idx) {
-            f(e.ptr(), e.size());
+            auto const& m = e.message();
+            auto cb = continuous_buffer(m);
+            f(cb.data(), cb.size());
+        }
+    }
+
+    /**
+     * @brief Apply f to stored messages.
+     * @param f applying function. f should be void(message_variant const&)
+     */
+    void for_each_store(std::function<void(message_variant const&)> const& f) {
+        LockGuard<Mutex> lck (store_mtx_);
+        auto& idx = store_.template get<tag_seq>();
+        for (auto const & e : idx) {
+            f(e.message());
         }
     }