Continuing the story of early DOS development

Stacey Haffner, Scott Hanselman· Apr 29, 2026 · 9:27 AM UTC ·1 min read · 0 reactions · 0 comments · 15 views

In 2018 we (re)-open-sourced MS‑DOS 1.25 and 2.11, and more recently in 2024 we were able to make the source for MS‑DOS 4.0 available to the public as well. Today, on 86-DOS 1.00’s 45th anniversary, we’re continuing that tradition with the earliest DOS source code discovered to date.

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Microsoft Open Source Blog · Stacey Haffner, Scott Hanselman

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Original publisher	Microsoft Open Source Blog
Canonical URL	https://opensource.microsoft.com/blog/2026/04/28/continuing-the-story-of-early-dos-development/
Publication time	Wed, 29 Apr 2026 09:27:50 +0000
Retrieval time	2026-04-29T10:06:15.560Z
Last seen	2026-04-29T10:06:15.560Z
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Opening excerpt (first ~120 words) tap to expand

Apr 30 • 4 min read PostgreSQL enters its AI era: Run PostgreSQL like a pro in the era of AI and rapid growth Postgres can handle intelligent workloads and scale without sacrificing security, performance, reliability, or operational ease.

Excerpt limited to ~120 words for fair-use compliance. The full article is at Microsoft Open Source Blog.

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