Hypothes.is: Brief report on the history, infrastructure, and demographics of the project.
Why is the project open? Is it for ideological reasons, or practical reasons, or both?
Both, at the start of the project, they surveyed all of the annotation projects that went before (and failed). There was one glaring trend: very few were open and all of them were for profit. Dan, the founder, came to the conclusion that annotation should be a basic web resource, not something to be owned.
How big is the community? Where are its members located? How did you find out?
Pretty big. There are many people interested in annotation for a bunch of vastly different use cases. Additionally, a core part of the Hypothes.is code base comes from the Open Knowledge Foundation's Annotator project. Hypothes.is is a key contributor to that project and that project has been a useful hub for building a community around open annotation. The community is global, with a large amount of interest coming from places such as the UK and New Zealand. In addition, two of our core developers are from Hungary. earlier this year, many of us got together for the annual iAnnotate conference where we could all talk about the importance of annotation and the many projects we're working on.
What kind of product is it and how is it licensed?
Hypothes.is is a bit strange in that we are making both software and a service. The software is licensed under a MIT License, so that others will be able to easily create their own annotation store, or modify the code for a very specific use case. However, we soon came to realize there's much more to annotation than just the tech, the real magic of it is the community of annotators, and so we have plans to create a service for open annotation of the web.
What sort of infrastructure does it use? Why does it use those tools and not other options?
We largely use GitHub, IRC, and mailing lists for collaboration and communication purposes. Our application uses a couple of open source frame works, notably Angular.js and Pyramid... choosen largely because of our lead developer's preference.