  For peer production communities to be sustainable, they must attract and
retain new contributors. Studies have identified social and technical barriers
to entry and discovered some potential solutions, but these solutions have
typically focused on a single highly successful community, the English
Wikipedia, been tested in isolation, and rarely evaluated through controlled
experiments. We propose the Newcomer Homepage, a central place where newcomers
can learn how peer production works and find opportunities to contribute, as a
solution for attracting and retaining newcomers. The homepage was built upon
existing research and designed in collaboration with partner communities.
Through a large-scale controlled experiment spanning 27 non-English Wikipedia
wikis, we evaluate the homepage and find modest gains, and that having a
positive effect on the newcomer experience depends on the newcomer's context.
We discuss how this impacts interventions that aim to improve the newcomer
experience in peer production communities.
