Teams can gain advice and support from organizers, volunteers, sponsors, and others.

All work on a project should be done at the hackathon.

Teams can use an idea they had before the event.

Teams can work on ideas that have already been done. Hacks do not have to be “innovative”. If somebody wants to work on a common idea they should be allowed to do so and should be judged on the quality of their hack. These days it’s hard to find something that’s fully original and teams might not know an idea has been done before anyway.

Teams can work on an idea that they have worked on before (as long as they do not re-use code).

Teams can use libraries, frameworks, or open-source code in their projects. Working on a project before the event and open-sourcing it for the sole purpose of using the code during the event is against the spirit of the rules and is not allowed.