I keep here a repository for experimental Gyoto packages. Whenever possible, Gyoto packages are made available through the official repositories and backports.
Currently, LORENE is sitting in the NEW queue. It will reach the official archive soon, depending on the priorities of the FTP team. For the impatient, you can use this repository in the interim. It contains Gyoto compiled for jessie (Debian 8.x, only for the amd64 architecture), plus the required dependencies: giza (backported from unstable) and LORENE.
To add my key to apt, run:
wget https://people.debian.org/~thibaut/debian/93945348E0DC2840.gpg
sudo apt-key add 93945348E0DC2840.gpg
Add the following lines to /etc/apt/sources.list:
deb http://people.debian.org/~thibaut/debian/ jessie-gyoto main
deb-src http://people.debian.org/~thibaut/debian/ jessie-gyoto main
To get gyoto and the run-time dependencies, run:
sudo apt update
sudo apt install -t jessie-gyoto gyoto