The language doesn't seem like the interesting part here. Bosque appears mainly to be a vehicle for exploring a different way of thinking about compiler IR. From the MSR site[1]:

> In the Bosque project we ask the question of what happens if the IR is designed explicitly to support the rich needs of automated code reasoning, IDE tooling, etc. With this novel IR first perspective we are exploring a new way to think about and build a language intermediate representation and tools that utilize it. Our initial experiments show that this empowers a range of next-generation experiences including symbolic-testing, enhanced fuzzing, soft-realtime compilation with stable GC support, API auto-marshaling, and more!

[1] https://www.microsoft.com/en-us/research/project/bosque-prog...