hermes --tui launches the native OpenTUI engine (Bun) when
HERMES_TUI_ENGINE=opentui (env) or display.tui_engine=opentui (config);
Ink stays the default and the shipping path is untouched.
- _resolve_tui_engine() (env > config > ink); refuses opentui on
Windows/Termux (no Bun) -> falls back to ink with a notice.
- _make_opentui_argv() -> [bun, src/entry.real.tsx] (no build step).
- _bun_bin() with HERMES_BUN override.
- Branch at top of _make_tui_argv BEFORE _ensure_tui_node (Bun-only host
must not bootstrap Node).
- Gate _launch_tui NODE_OPTIONS/--max-old-space-size on engine==ink (Bun
is JSC; the V8 flag errors/ignores).
Verified end-to-end via tmux: real hermes --tui -> Bun -> OpenTUI ->
real Python gateway streamed a real reply. No-flag default still ink.
test_concurrent_compressions_same_session_serialize relied on a
time.sleep(0.25) inside the stubbed compressor to make the two threads
overlap inside the per-session lock window. Under CI CPU starvation that
sleep is insufficient: one thread can acquire -> compress -> rotate ->
RELEASE the lock before the other reaches try_acquire, so both acquire on
the shared session_id and both compress (the recurring 'Expected exactly
one agent to compress, got 2' failure on shard test (1)).
Replace the timing dependency with a threading.Barrier(2) wrapped around
the shared db's try_acquire_compression_lock: both threads rendezvous
immediately before the real (atomic) acquire, guaranteeing genuine
simultaneous contention regardless of scheduling. The real lock logic is
unchanged and still picks exactly one winner — this only fixes the test's
overlap guarantee. Restored after join so the post-join lock-leak
assertion hits the unwrapped method.
Verified: 20/20 plain + 15/15 under all-core CPU stress (load avg ~4.6),
where the old version flaked.
