Xpiks is only possible because of the awesome open-source projects that power it. Listed in no particular order.
Qt framework is an awesome cross-platform framework for C++ maintained by The Qt Company and community.
curl is one of the best networking libraries maintained by Daniel Stenberg.
zlib is one of the most commonly used compression libraries in the world written by Jean-loup Gailly (compression) and Mark Adler (decompression).
hunspell is the leading spelling library used in LibreOffice, Mozilla Firefox and Google Chrome.
exiftool is one the best metadata editing applications developed by Phil Harvey.
quazip is a Qt/C++ wrapper over minizip/zlib library created by Sergei Tachenov.
FFmpeg is a collection of video and audio codecs created by numerious contributors.
openSSL is the most commonly used library for the Transport Layer Security (TLS) and Secure Sockets Layer (SSL) protocols.
SQLite is one of the most used databases that is in the public domain and maintained by Richard Hipp.