diff --git a/ap/flatpak/flatpak-0.11.3.tar.xz.sha256 b/ap/flatpak/flatpak-0.11.3.tar.xz.sha256
new file mode 100644
index 00000000..860bd2a7
--- /dev/null
+++ b/ap/flatpak/flatpak-0.11.3.tar.xz.sha256
@@ -0,0 +1 @@
+ae580c8ef7b82e3501c36625ebf6b8421e67629ea4862b1233c292a3f548b672  flatpak-0.11.3.tar.xz
diff --git a/ap/flatpak/flatpak.SlackBuild b/ap/flatpak/flatpak.SlackBuild
new file mode 100755
index 00000000..12aac917
--- /dev/null
+++ b/ap/flatpak/flatpak.SlackBuild
@@ -0,0 +1,132 @@
+#!/bin/bash
+# Build script for Slackware
+# Copyright (C) 2018 Damien Goutte-Gattat
+#
+# Redistribution and use of this script, with or without modifications,
+# is permitted provided that the following conditions are met:
+#
+# 1. Redistributions of this script must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AS IS'' AND ANY EXPRESS OR
+# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+# INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+# IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+#
+# Contact: Damien Goutte-Gattat <dgouttegattat@incenp.org>
+#
+# Latest flatpak sourcecode is available at: <http://flatpak.org/>.
+#
+# Depends: l/libostree, l/appstream-glib
+
+# Source package infos
+NAMESRC=${NAMESRC:-flatpak}
+VERSION=${VERSION:-0.11.3}
+ARCHIVE=${ARCHIVE:-$NAMESRC-$VERSION.tar.xz}
+WGET=${WGET:-https://github.com/flatpak/flatpak/releases/download/$VERSION/$ARCHIVE}
+
+# Build infos
+NAMEPKG=${NAMEPKG:-flatpak}
+BUILD=${BUILD:-1GGD}
+ARCH=${ARCH:-$(uname -m | sed 's/^i.86$/i486/;s/^arm.*/arm/')}
+JOBS=${JOBS:-1}
+EXT=${EXT:-txz}
+
+# Directories
+TMP=${TMP:-/tmp}
+OUT=${OUT:-$TMP/build}
+PKG=${PKG:-$OUT/$NAMEPKG}
+CWD=$(pwd)
+
+set -e  # Quit if a command returns non-zero
+
+# Sanity checks
+if [ $UID -eq 0 ]; then
+    echo "You should NOT run this script as ROOT!"
+    exit 1
+fi
+if [ ! -d $TMP ]; then
+    echo "$TMP does not exists or is not a directory!"
+    exit 1
+fi
+
+# Compilation flags
+LIBDIRSUFFIX=""
+case "$ARCH" in
+i?86)
+    CPUOPT="-O2 -march=$ARCH -mtune=i686"
+    ;;
+x86_64)
+    CPUOPT="-O2 -fPIC"
+    LIBDIRSUFFIX="64"
+    ;;
+*)
+    CPUOPT="-O2"
+    ;;
+esac
+
+# Get and verify the source archive
+if [ ! -r $ARCHIVE ]; then
+    wget -c -O $ARCHIVE.part "$WGET"
+    mv $ARCHIVE.part $ARCHIVE
+fi
+sha256sum -c $ARCHIVE.sha256
+NAME=$(tar ft $ARCHIVE | head -n 1 | cut -d / -f 1)
+
+# Compile
+cd $TMP
+echo "Building $ARCHIVE..."
+tar xf $CWD/$ARCHIVE
+cd $NAME
+CFLAGS=$CPUOPT \
+CXXFLAGS=$CPUOPT \
+./configure \
+  --prefix=/usr \
+  --libdir=/usr/lib$LIBDIRSUFFIX \
+  --sysconfdir=/etc \
+  --mandir=/usr/man \
+  --infodir=/usr/info \
+  --docdir=/usr/doc/$NAME \
+  --disable-dependency-tracking \
+  --disable-seccomp \
+  --build=$ARCH-slackware-linux
+make -j $JOBS
+make install-strip DESTDIR=$PKG
+
+# Compress man pages
+find $PKG/usr/man  -type f -exec gzip -9 {} \;
+
+# Install the documentation
+mkdir -p $PKG/usr/doc/$NAME
+install -m 644 COPYING NEWS README.md $PKG/usr/doc/$NAME
+
+# Copy slack-desc file
+install -D -m 644 $CWD/slack-desc $PKG/install/slack-desc
+
+# Add dependency infos
+cat <<EOF > $PKG/install/slack-required
+libostree
+appstream-glib
+EOF
+
+# Package the tree
+cd $PKG
+mkdir -p $OUT
+PACKAGING="
+chown root:root . -R
+/sbin/makepkg -l y -c n $OUT/$NAMEPKG-$VERSION-$ARCH-$BUILD.$EXT
+rm -rf $PKG
+rm -rf $TMP/$NAME
+"
+if type -p fakeroot ; then
+    echo "$PACKAGING" | fakeroot
+else
+    su -c "$PACKAGING"
+fi
diff --git a/ap/flatpak/slack-desc b/ap/flatpak/slack-desc
new file mode 100644
index 00000000..ac13c0b5
--- /dev/null
+++ b/ap/flatpak/slack-desc
@@ -0,0 +1,12 @@
+       |-----handy-ruler-----------------------------------------------------|
+flatpak: flatpak (sandboxed applications for Linux)
+flatpak: 
+flatpak: Flatpak is a system for building, distributing and running sandboxed
+flatpak: desktop applications on Linux.
+flatpak: 
+flatpak: 
+flatpak: 
+flatpak: 
+flatpak: 
+flatpak: 
+flatpak: