php7 on Raspbian

sources.list

Add the following lines

sudo vi /etc/apt/sources.list

add

deb http://repozytorium.mati75.eu/raspbian jessie-backports main contrib non-free
#deb-src http://repozytorium.mati75.eu/raspbian jessie-backports main contrib non-free

install key

sudo gpg --keyserver pgpkeys.mit.edu --recv-key CCD91D6111A06851
sudo gpg --armor --export CCD91D6111A06851 | sudo apt-key add -

update

sudo apt-get update

Install php7

sudo apt-get install php7.1 php7.1-mysql mariadb-server-10.0