gEDA
The gEDA project has produced and continues working on a full GPL'd suite and toolkit of Electronic Design Automation tools. These tools are used for electrical circuit design, schematic capture, simulation, prototyping, and production.
Fork lepton-eda https://github.com/lepton-eda/lepton-eda
SlackBuilds
1 cd /tmp
2 wget http://ftp.geda-project.org/geda-gaf/stable/v1.8/1.8.2/geda-gaf-1.8.2.tar.gz
3 wget http://slackbuilds.org/slackbuilds/14.1/academic/geda-gaf.tar.gz
4 tar xvzf geda-gaf.tar.gz
5 mv geda-gaf-1.8.2.tar.gz geda-gaf/
6 cd geda-gaf
7 ls
8 ./geda-gaf.SlackBuild
9 installpkg /tmp/geda-gaf-1.8.2-i486-1_SBo.tgz