Raft Lab

Distributed-systems students and interview candidates read the Raft paper but never see elections, term fencing and log reconciliation happen; existing visualizers are canned animations you cannot break, so the failure modes never become intuitive.

What's interesting about it

• The hard part is a deterministic, tick-driven Raft implementation (elections, log replication, commit rules) that is also the engine driving the UI, plus property-based tests proving safety invariants (at most one leader per term, election restriction, log matching, committed-prefix) across thousands of random crash/partition scenarios; success is measured by those invariants holding under fuzzing and by the UI replaying any failing seed step by step.