:

MICROSOFT OPEN-SOURCES EARLIEST DOS CODE EVER FOUND

INDUSTRY DESK1 MIN READ
SAT, MAY 23, 2026

■ AI-SUMMARIZED FROM 3 SOURCES ▸ TIMELINE

Microsoft has released the source code for 86-DOS, predating the company's 1981 acquisition of the operating system. The release marks a significant moment for computing history.

The open-sourced code dates back to before Microsoft purchased DOS, providing developers and historians with a rare glimpse into the early foundations of personal computing. The move underscores Microsoft's recent shift toward transparency around legacy technology. In other Microsoft updates, the company has fixed a bug causing Windows security warnings to display incorrectly when opening Remote Desktop (.rdp) files. Meanwhile, Microsoft is testing a modernized Windows 11 Run menu for Insiders in the Experimental Channel. The redesign introduces dark mode support and improved performance. The company removed the "Browse" button after discovering minimal user adoption, replacing it with a new "~\" command for direct home directory access. The refresh aims to bring the decades-old Run utility into line with modern Windows design standards.

■ SOURCES

Ars TechnicaBleeping ComputerThe Verge

■ SUMMARY WRITTEN BY AI FROM THE LINKS ABOVE

■ MORE FROM THE DEV DESK

A software developer makes the case that AI tools should be integrated more widely into everyday work processes, challenging hesitation around their use.

13H AGOAI Desk

GitHub experienced a significant incident affecting pull requests, issues, git operations, and API requests. The outage generated substantial community discussion across tech forums.

YESTERDAYDev Desk

PostHog is training its own AI models rather than relying solely on third-party providers. The move reflects a broader trend of companies developing custom AI capabilities for competitive advantage and data control.

MAY 27AI Desk

GitHub Actions went down again today, disrupting CI/CD workflows for developers. The outage status was tracked on GitHub's status page with significant community discussion on Hacker News.

MAY 26AI Desk

■ SUBSCRIBE TO THE DAILY BRIEF

ONE EMAIL, 5 STORIES, 06:00 UTC. UNSUBSCRIBE ANYTIME.