[1] In 2003, Michlmayr was elected as Debian Project Leader;[2][3] he was re-elected to that position one year later, in 2004.

[6] Additionally, Michlmayr made various contributions to Debian's quality assurance effort.

This work resulted in the identification of compiler bugs as well as build errors in many open source packages.

The focus of this research was on quality improvement in free software and open source projects, and particularly on release management processes and practices.

[11] Between 2008 and 2014[12] Michlmayr served on the board of directors of the Open Source Initiative, acting as the organization's secretary.