Original sentence: Gumstix freely publishes the expansion and layouts online at  under the Creative Commons Share-alike license, but the computer-on-module schematics are proprietary.Gumstix products come with a 30 day limited warranty.Gumstix started as the name of a single-board computer, developed as a hobby project by Gordon Kruberg.The design of the main computer PCB has always been proprietary, but expansion boards and software follow an open model
Edited sentence: Gumstix was initially the name of a single-board computer, developed as a hobby project by Gordon Kruberg.The software stack is Linux based, built using the OpenEmbedded framework.While the design of the main computer boards have always been proprietary, designs for expansion boards are published under a Creative Commons Share-alike license