Gate run 5888 failed: the synastry full dossier computes two full readings on a thread pool, and the second thread got jyotish_engine from sys.modules while the first was still executing it (no cmd_full_reading yet). Reuse now goes through importlib.import_module, which waits on the module lock. Four threads loading one module in a fresh interpreter: before [False, True, True, True], after all True three times. Dossier scenario before 4/4 AttributeError, after 6/6 ok; synastry-full-report.test.ts 17/17. Ledger ERR-117: local npm baseline hid it (system python3 lacks swisseph). Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>