RevTrace: version control built into Altium Designer. I conceived and built it alone in C#/.NET to replace a team habit of storing full project copies in Google Drive. Engineers commit revisions, branch from any earlier project state, compare revisions visually and restore selected changes without rolling back the whole project. I did the architecture, Altium integration, revision logic, comparison and restore mechanisms, installer and workflow. Adopted by all 5 engineers on my former team and still in use after I left.