What is Backporting?
Sometimes we need to run newer versions of the package on our system but that is not available in the current stable release. However it is available in the Debian testing branch, which we can't update to our current package normally by apt-get update. So in order to have that newer version package on our system we need to install it forcefully on our risk because it may break the other packages which are dependent on it. This process is known as backporting.
Command to perform backporting:
$ apt-get -t jessie-backports <package_name>
- Package needed to build: "ruby-diaspora-federation-rails"
- Pre-requisite Packages: git-buildpackage, quilt
git clone https://anonscm.debian.org/cgit/pkg-ruby-extras/ruby-diaspora-federation-rails.git
Run the command gbp buildpackage
- Result - Build Failed
Reason - dpkg-checkbuilddeps: Unmet build dependencies: ruby-diaspora-federation (>= 0.0.6) ruby-rails (>= 4.2)
Follow the same steps for all the unmet dependencies. If the dependency is available in the jessie repository then you can install directly using apt-get.