My `/etc/apt/sources.list` for Debian 8 (Jessie)

# The official Debian repository
deb http://ftp.debian.org/debian stable main contrib non-free
# The Debian source code.
# It could be needed to compile something manually.
# E.g., I have used it to compile PHP and PHP extensions manually.
deb-src http://ftp.debian.org/debian stable main contrib non-free

# Debian updates
deb http://ftp.debian.org/debian/ jessie-updates main contrib non-free
deb-src http://ftp.debian.org/debian/ jessie-updates main contrib non-free

# Debian security updates
deb http://security.debian.org/ jessie/updates main contrib non-free
deb-src http://security.debian.org/ jessie/updates main contrib non-free

# Debian proposed Updates
deb ftp://ftp.debian.org/debian jessie-proposed-updates main contrib non-free

# PostgreSQL 9.5
deb http://apt.postgresql.org/pub/repos/apt/ trusty-pgdg main 9.5

# For Docker
# 2017-04-29
# Now it is used to install Certbot too.
# I use Certbot to install and automatically update my Let's Encrypt certificates.
# https://www.digitalocean.com/community/tutorials/how-to-secure-nginx-with-let-s-encrypt-on-debian-8#step-1-install-certbot-the-let-39-s-encrypt-client
deb http://ftp.debian.org/debian jessie-backports main

# 2017-04-29 For PHP 7.1: https://mage2.pro/t/2428
deb https://packages.sury.org/php/ jessie main