If you trust us, do for stable releases: wget http://apertium.projectjj.com/apt/install-release.sh -O - | sudo bash or for nightly updates: wget http://apertium.projectjj.com/apt/install-nightly.sh -O - | sudo bash Otherwise, follow these instruction... Firstly, add the repository signing key to your apt keyring with either: sudo apt-get install wget sudo wget http://apertium.projectjj.com/apt/apertium-packaging.public.gpg -O /etc/apt/trusted.gpg.d/apertium.gpg or: sudo apt-get install wget wget http://apertium.projectjj.com/apt/apertium-packaging.public.asc -O - | sudo apt-key add - Then, add your chosen repository to apt sources with: echo "deb http://apertium.projectjj.com/apt/nightly $DISTRO main" | sudo tee /etc/apt/sources.list.d/apertium-nightly.list Replace $DISTRO with one of: jessie stretch sid precise utopic wily xenial Then, use it with e.g.: sudo apt-get update sudo apt-get install apertium-kaz-tat echo "Барлық адамдар тумысынан азат және қадір-қасиеті мен кұқықтары тең болып дүниеге келеді." | apertium kaz-tat