The functionality in each build should be stable. We are very committed to fixing bugs and getting existing code solid before moving on to new features. However Fantom is still new, and like all software platforms it still needs to be wrung out in lots of different applications.
We can't promise that we won't make breaking language or API changes. We need the freedom to change things as we learn what does and does not work. However in practice, we've made very few breaking changes over the past year.
Random list of ideas for future work we have on our radar, or that we would like to see receive community attention:
By far and awaw the biggest requirement for a successful ecosystem is awesome tooling. The community is doing a great job addressing IDE tooling, and if you are interested please get involved!
We need standardized APIs for cryptographic operations and algorithms. This work will include support for the SSL protocol.
.NET and Alternate Runtimes