def next_slot
import cswap-bend-cli@0.1.0.0/store/seq.bend as Seqimport Base
import cswap-bend-cli@0.1.0.0/json.bend as Json
107# max(slot) + 1, or 1 for an empty roster.
108def next_slot(+seq: Json.Json) -> U32:
109 (max_in(fields_of(seq), 0) + 1 : U32)