The corpus carried hand-written :expected values — a regression suite but a weak
spec (it checked jolt against its authors, not against Clojure). certify.clj runs
every corpus row's :actual and :expected through reference JVM Clojure 1.12.5 (fresh
user ns per case, output/stdin sunk, 5s per-case watchdog) and compares with =.
Result: of ~2487 vanilla-certifiable rows, 2416 match real Clojure exactly. The 71
divergences are all classified in known-divergences.edn — mostly deliberate
jolt-specific/host-model deltas (all-double numerics, snapshot concurrency, no-JVM
host model, jolt reader features, printer, strictness), plus 4 genuine bugs filed
as beads (jolt-l8e8 ex-message, jolt-hc35 munge, jolt-pqio print-nil,
jolt-2507 bounded-count).
certify-test.janet gates it: skips without clojure on PATH, else fails only on a
NEW (unclassified) divergence or stale allowlist entry; flaky timing-dependent
cases (future-cancel) tolerated either way. Full gate 155 files 0 failed.