Around 2007 Patrick Debois was working on a large data center migration as in charge of testing. During this project, he realized that the frustrations experienced from the constant switching back and forth between the development side and operations side. Patrick Debois had worked on all aspects of the software lifecycle, like developer, network specialist, system administrator, tester and project manager which gave allowed him to break past silo-based organizational boundaries.
Later, in 2008 during an Agile conference held in Toronto, Canada, Andrew Shafer tried to put together a meetup session entitled “Agile Infrastructure”. No one registered for this session and Andrew himself never turned up for his own session. Patrick hunted down Andrew during the conference and started a conversation which lead to the evolution of devops. Additional details can be found in the below video by Damon Edwards
https://www.youtube.com/watch?v=o7-IuYS0iSE
The famous John Allspaw (Flickr/Yahoo!) and Paul Hammond (Flickr) titled “10+ Deploys Per Day: Dev and Ops Cooperation at Flickr” and presented at Velocity 2009 Conference