The group is currently working on creating a dependently typed language based on homotopy type theory (HoTT).
The project's ultimate goal is to create an online collaborative proof assistant based on a modern type theory to allow a formalization of certain branches of mathematics.
The project started incidentally in 2012 when one of the teams at JetBrains was developing a collaborative real-time editor based on operational transformation (OT). With the help of Coq proof assistant, a suitable OT algorithm was developed and validated, but the interest in automated proof checking and formal verification as applied to real-world tasks led to a creation of a separate research group. In 2015 the group switched over to the development of the experimental HoTT language.
Official website: https://arend-lang.github.io/
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