Slashdot has reported:

A release of about 1.5 GB of Palm OS development resources has led developer Ardiri to rediscover a working virus he created and tested in June 2001. The resources, preserved on hard drive backups for more than 25 years, are available at GitHub.com/ardiri/dev-palmos for historical preservation, education and research.

The archive contains historical software development kits, developer conference presentations, technical documentation, programming examples, limited source code and development utilities. ROM images, commercial applications and simulator binaries were deliberately excluded. The collection is intended to support retrocomputing enthusiasts maintaining, emulating and reviving the platform.

Ardiri found the virus source code on a CompactFlash card among files dated June 2001. He had developed and tested it months before a planned PalmSource developer conference in San Jose. The discovery is described in “The Palm OS Virus That Never Was - Lost for 25 Years, Found in 2026.”

Named “Virii,” the virus intercepted Palm OS system calls to infect legitimate applications progressively while retaining their original functions. Those applications could then pass the virus between handheld devices through infrared beaming. The potential spread among developers exchanging software at the conference could have reached hundreds of people.

The virus also had a payload set to activate between October 23 and 27, 2001. It was designed to interfere with system time reporting, with possible effects including erratic clocks, unreliable alarms and missed appointments. Ardiri said the functional source code and binaries would remain private.

Ardiri remembers his years writing applications for Palm OS. He said the archived materials had been “accumulated during the early days of handheld computing and preserved on hard drive backups for more than 25 years... to preserve the tools and knowledge that helped define an important era of personal computing.” He has also written an autobiography and has started exploring the engineering principles behind these systems in his books.