Barrier Cuts & Epoch Snapshots
Coordinated state snapshots across multi-partition streaming topologies.
A Krabka broker injects epoch-stamped marker records into every partition of a named barrier group, publishing the resulting cut on the internal topic __barrier_state.
A cut is an exact, coordinated point in every input stream simultaneously. Stream runners snapshot their state at the cut and commit the cut offsets, enabling exact replay and recovery to specific historical epochs.