Continuing the story of early DOS development

Microsoft is continuing its effort to preserve early DOS history by releasing the earliest DOS source code discovered to date, on the 45th anniversary of 86-DOS 1.00. A team of historians led by Yufeng Gao and Rich Cini located, scanned, and transcribed assembler listings from Tim Paterson, the original author of DOS. The materials include sources to the 86-DOS 1.00 kernel, PC-DOS 1.00 development snapshots, and utilities like CHKDSK. These listings function like a printed commit history, showing how features were implemented and bugs fixed. The code is licensed under MIT and hosted at DOS-History/Paterson-Listings on GitHub. Physical artifacts will also be donated to the Interim Computer Museum.