833
Microsoft Just Released MS-DOS Source Code!
(github.com)
All about open source! Feel free to ask questions, and share news, and interesting stuff!
Community icon from opensource.org, but we are not affiliated with them.
They probably only got clearance from their lawyers (or IBM's lawyers) just now.
A lot of proprietary software includes bits from other proprietary software that they don't have the rights to open-source. And untangling and removing those bits takes time and effort.