Post Anger Rant (Beware, Long rant ahead)

So there is this project we have been working for months, most of the devs involved are jr students so I was leading them in the architecture and what to do and they were doing it, the progress was slow but safe and fun.

On the team there was this guy, someone I trusted and in who I had special interest for his skills, so I let him own the github repo.

So the day of the first demo I pull the backend changes ( I had been working on front end ) and I realize that the code was different, so I started using my super awesome forensic skills to find what happened,and when I say different I mean a totally different architecture different database connections, different service pirts, basically other project, so during my criminal investigation I found out this guy I trusted had never really worked with us, from the beginning he went solo working on his own project and changing everything because of some tutorial he found on the internet, so I decided to reset to the previous version just to find out that he had already deployed the code and that a lot of fixes that we should have were only on his version.

So I went and confront him telling him that he did wrong and he had to learn team work and that I was trying to teach them good practices and he waits and asks me "so, my code was wrong?" Seriously what da hell dude? I'm talking about team work and all you can think about is your code.

Finally he admitted his mistake and repented (I think), but seriously how arrogant must you be to ignore a whole team, specially when on your first real project.