diff --git a/.travis.yml b/.travis.yml
index b089c7c3751..de3a37044cd 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,6 +8,7 @@ cache:
   ccache: true
   directories:
     - $HOME/build-cache
+    - $HOME/flatpak-cache
 
 git:
   depth: 5
@@ -36,6 +37,8 @@ matrix:
     
     - env: CXXSTD=14 NLS=false LTS=steamrt BRANCH=master CC=gcc-5 CXX=g++-5
 
+    - env: NLS=true LTS=flatpak BRANCH=master
+
     - os: osx
       compiler: clang
       env: TOOL=scons CXXSTD=14 NLS=false OPT=-O0
diff --git a/packaging/flatpak/org.wesnoth.Wesnoth.json b/packaging/flatpak/org.wesnoth.Wesnoth.json
index 9c024efca0e..e002aec8e8f 100644
--- a/packaging/flatpak/org.wesnoth.Wesnoth.json
+++ b/packaging/flatpak/org.wesnoth.Wesnoth.json
@@ -19,6 +19,14 @@
         "/share/man",
         "*.la", "*.a"
     ],
+    "build-options": {
+        "cflags-override": true,
+        "cppflags-override": true,
+        "cxxflags-override": true,
+        "cflags": "",
+        "cppflags": "",
+        "cxxflags": ""
+    },
     "modules": [
         {
             "name": "boost",
@@ -32,7 +40,7 @@
             ],
             "build-commands": [
                 "./bootstrap.sh --prefix=/app --with-libraries=filesystem,locale,iostreams,program_options,regex,random,thread",
-                "./b2 -j4 install cxxflags='-fPIE -fstack-protector-strong' define=_FORTIFY_SOURCE=2 link=static variant=release address-model=64 --layout=system"
+                "./b2 -j$FLATPAK_BUILDER_N_JOBS install cxxflags='-fPIE -fstack-protector-strong' define=_FORTIFY_SOURCE=2 link=static variant=release address-model=64 --layout=system"
 ]
         },
 	{
@@ -57,7 +65,7 @@
                 "/share/applications/wesnoth_editor.desktop"
             ],
             "build-commands": [
-                "python3 /app/bin/scons -j $FLATPAK_BUILDER_N_JOBS prefix=/app ccache=true install wesnoth wesnothd"
+                "python3 /app/bin/scons -j $FLATPAK_BUILDER_N_JOBS prefix=/app ccache=true --debug=time install wesnoth wesnothd"
 	    ],
             "sources": [
                 {
diff --git a/utils/dockerbuilds/travis/Dockerfile-base-flatpak b/utils/dockerbuilds/travis/Dockerfile-base-flatpak
new file mode 100644
index 00000000000..913bb9e3cd6
--- /dev/null
+++ b/utils/dockerbuilds/travis/Dockerfile-base-flatpak
@@ -0,0 +1,11 @@
+FROM wesnoth/wesnoth:1804-master
+
+# install ppa for more recent flatpak version, otherwise "dir" source type is unrecognized
+RUN apt install -y software-properties-common
+RUN add-apt-repository -y ppa:alexlarsson/flatpak
+RUN apt update
+# install flatpak
+RUN apt install -y flatpak flatpak-builder jq
+RUN flatpak remote-add flathub https://flathub.org/repo/flathub.flatpakrepo
+# install runtime
+RUN flatpak install -y flathub org.freedesktop.Platform/x86_64/19.08 org.freedesktop.Sdk/x86_64/19.08
diff --git a/utils/travis/docker_run.sh b/utils/travis/docker_run.sh
index b50814ef73f..5dff106cb5e 100755
--- a/utils/travis/docker_run.sh
+++ b/utils/travis/docker_run.sh
@@ -26,7 +26,7 @@ BOOST_TEST="${11}"
 LTO="${12}"
 SAN="${13}"
 VALIDATE="${14}"
-TYPE="${15}"
+LTS="${15}"
 
 if [ "$OPT" == "-O0" ]; then
     STRICT="true"
@@ -55,25 +55,39 @@ echo "BOOST_TEST: $BOOST_TEST"
 echo "LTO: $LTO"
 echo "SAN: $SAN"
 echo "VALIDATE: $VALIDATE"
-echo "TYPE: $TYPE"
+echo "LTS: $LTS"
 
 echo "STRICT: $STRICT"
 echo "build_timeout(mins): $build_timeout"
 
 $CXX --version
 
-if [ "$NLS" == "true" ]; then
+if [ "$NLS" == "true" ] && [ "$LTS" != "flatpak" ]; then
     cmake -DENABLE_NLS=true -DENABLE_GAME=false -DENABLE_SERVER=false -DENABLE_CAMPAIGN_SERVER=false -DENABLE_TESTS=false
     make VERBOSE=1 -j2 || exit 1
     make clean
 
     scons translations build=release --debug=time nls=true jobs=2
-elif [ "$TYPE" == "mingw" ]; then
+elif [ "$LTS" == "flatpak" ]; then
+# docker's --volume means the directory is on a separate filesystem
+# flatpak-builder doesn't support this
+# therefore manually move stuff between where flatpak needs it and where travis' caching can see it
+
+    rm -R .flatpak-builder/*
+    cp -R flatpak-cache/. .flatpak-builder/
+    jq '.modules[2].sources[0]={"type":"dir","path":"/home/wesnoth-travis"} | ."build-options".env.FLATPAK_BUILDER_N_JOBS="2"' packaging/flatpak/org.wesnoth.Wesnoth.json > utils/dockerbuilds/travis/org.wesnoth.Wesnoth.json
+    flatpak-builder --ccache --force-clean --disable-rofiles-fuse wesnoth-app utils/dockerbuilds/travis/org.wesnoth.Wesnoth.json
+    BUILD_RET=$?
+    rm -R flatpak-cache/*
+    cp -R .flatpak-builder/. flatpak-cache/
+    chmod -R 777 flatpak-cache/
+    exit $BUILD_RET
+elif [ "$LTS" == "mingw" ]; then
     scons wesnoth wesnothd build=release \
         cxx_std=$CXXSTD opt="$OPT" strict="$STRICT" \
         nls=false enable_lto="$LTO" sanitize="$SAN" jobs=2 --debug=time \
         arch=x86-64 prefix=/windows/mingw64 gtkdir=/windows/mingw64 host=x86_64-w64-mingw32
-elif [ "$TYPE" == "steamrt" ]; then
+elif [ "$LTS" == "steamrt" ]; then
     scons ctool=$CC cxxtool=$CXX boostdir=/usr/local/include boostlibdir=/usr/local/lib extra_flags_config=-lrt \
         cxx_std=$CXXSTD opt="$OPT" strict="$STRICT" nls=false enable_lto="$LTO" sanitize="$SAN" jobs=2 --debug=time \
         build=release
diff --git a/utils/travis/steps/script.sh b/utils/travis/steps/script.sh
index e6833d843d2..c7b726621ee 100755
--- a/utils/travis/steps/script.sh
+++ b/utils/travis/steps/script.sh
@@ -40,8 +40,10 @@ if [ "$TRAVIS_OS_NAME" = "osx" ]; then
         fi
     fi
 else
-    docker run --cap-add=SYS_PTRACE \
+# additional permissions required due to flatpak's use of bubblewrap
+    docker run --cap-add=ALL --privileged \
     					 --volume "$HOME"/build-cache:/home/wesnoth-travis/build \
+    					 --volume "$HOME"/flatpak-cache:/home/wesnoth-travis/flatpak-cache \
                --volume "$HOME"/.ccache:/root/.ccache \
                --tty wesnoth-repo:"$LTS"-"$BRANCH" \
                unbuffer ./utils/travis/docker_run.sh "$NLS" "$TOOL" "$CC" "$CXX" "$CXXSTD" "$OPT" "$WML_TESTS" "$WML_TEST_TIME" "$PLAY_TEST" "$MP_TEST" "$BOOST_TEST" "$LTO" "$SAN" "$VALIDATE" "$LTS"