Comment by DSpinellis
5 hours ago
30 years ago (1995) open source offerings: mostly CVS for large projects and RCS for smaller ones. On the proprietary side, the aged SCCS was available and used, while Perforce and Microsoft Visual Source Safe were being launched.
(Meanwhile, apparently MS itself continued using SLM, the in-house source-control system which had been commercialised as MS Delta, internally until about 2000. https://news.ycombinator.com/item?id=44255526 )