Broadcast a message to all participants at any time.

It'd be nice to have this option in case both parties agree to record so we can replay during debrief

A good developer can performs a fast solution. If exists some questions that check the execution time and compare it with a expected time, this will be so good to know if the developer knows the fastest algorithms. Another suggestion is to verify the algorithm complexity. Thus, if the question expected a solution O(1) but the developer solved using a O(n) for example, then it will be useful to check the develoler knowledge.

I would like to have an option to edit like I am in vim. Minimal options are fine, but navigation and selections are easier for me in vim style editing.

Add c++ 17 support. It adds many new features. Also update versions of other programming languages (if applicable).

Add intelligent API suggestions to your IDE similar to how https://repl.it/languages/java10 works.