The LibreOffice Paris HackFest 2019 will take place on the weekend of July 5th-6th, at le 137, which is at 137 Boulevard Magenta, Paris 10e, France. The event is sponsored by INNO3, hosting the hackfest in their building, and The Document Foundation, providing reimbursement for travels and accommodations.
LibreOffice Paris HackFest will start on Friday at 10AM. During the day there will be an informal meeting of the French community, to discuss local activities, while developers and other volunteers will hack the LibreOffice code. The venue will be available until 2AM. On Saturday the venue will open at 10AM, to allow people to continue working, and share hackfest results. The event will officially end at 8PM, but on Sunday there will be a city tour.
More details on the LibreOffice Paris HackFest are available on the wiki at the following link: https://wiki.documentfoundation.org/Hackfest/Paris2019.