A few comments:
* The core idea sounds interesting. Make it the first paragraph, not paragraph seven.
* Spend more words describing what makes Oak different.
* "I built a version control system in my free-time called Jam". You probably didn't name your free time. "I built a version control system, called Jam, in my free time."
"I built a version control system, in my free-time, called Jam" is fine.