value-host-tags returned only ("Object") for a record, so a protocol extended to
clojure.lang.IRecord / IPersistentMap / Associative / Seqable / … (and not to the
record's own type) dispatched to the Object default. core.logic extends IWalkTerm
to IRecord, and walking a record value hit Object's (walk-term [v f] (f v)) — which
re-enters walk* and loops forever (the test-53-lossy-records hang).
A defrecord now carries the map/record interface tags it genuinely satisfies. The
record's own type is still tried first (jrec-tag, before these tags), so a direct
extend to the record type wins, and record equality / map? / record? are unchanged.
A bare deftype stays opaque (its tag + Object; declared interfaces dispatch via its
inline methods). Runtime only, no re-mint.
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