Installing PHP7.0 from sid on jessie

You have unofficial repos with new versions. Using Debian one of the best well-known repository for most up-to-date software for web servers for i386 and amd64 packages is dotdeb.

"Dotdeb is an extra repository providing up-to-date packages for your Debian servers"

They have PHP 7 since the 3rd of December (of 2015), and have had a pre-packaged beta since November.

To add the dotdeb repository, from here.

Edit /etc/apt/sources.list and add

deb http://packages.dotdeb.org jessie all

Fetch the repository key and install it.

wget https://www.dotdeb.org/dotdeb.gpg
sudo apt-key add dotdeb.gpg

Do then

sudo apt-get update

And lastly:

sudo apt-get install php7.0

To search for php 7 related packages:

apt-cache search php | grep ^php7

In Ubuntu you also already have PPAs for it too.

It seems Debian backports do not have yet PHP 7.0. Search here in a near future.

Add the main repository to your sources.list : Depending on your distribution (Jessie, Wheezy or Squeeze), add these two lines to your /etc/apt/sources.list file.

deb http://packages.dotdeb.org jessie all
deb-src http://packages.dotdeb.org jessie all

For PHP 7.0 on Debian 8 “Jessie” (rc3), add these two lines too :

deb http://packages.dotdeb.org jessie-php7.0 all
deb-src http://packages.dotdeb.org jessie-php7.0 all

Fetch and install the GnuPG key :

wget https://www.dotdeb.org/dotdeb.gpg
sudo apt-key add dotdeb.gpg

Run apt-get update && apt-get install php7-*