# NousResearch/hermes-agent · Concurrent lazy SDK import crashes and byte-compile fixes

## Open now

- Nothing open on GitHub.

These items address crashes and stalls caused by concurrent cold-start imports of lazily installed backends, particularly the Anthropic SDK on CPython 3.12. Fixes involve serializing imports with thread locks and byte-compiling backends at install time.

## TL;DR

- 5 member(s): 0 open issue(s), 1 closed issue(s), 0 open PR(s), 1 merged PR(s), 3 PR(s) closed without merging.
- A fix was merged to main in PR #100911. Verify it addresses your case.
- **Recommended:** read PR #100911 (and any competing PRs below) before filing. Confirm the merged change covers your symptom.

## Maintainer resolution verdict

- Internal-tracker verdict over this cluster's issue members: `unresolved`. This is distinct from the fix status above. Weigh it yourself.

## How this cluster was grouped

- Link evidence (`STRUCTURAL_SPANNING`): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.
- Pairwise link density `0.40`: the share of member pairs that carry a link, counting a structural link in full and a relevance-only link at 0.36. `1.00` means every pair is linked.

## Closed / duplicate issues

- #100461: v0.21.0: anthropic SDK import crashes on cpython-3.12.13 typing recursion (concurrent cold-start)

## Prior & competing PRs

- **#100911: Lazily installed backends are byte-compiled at install time so first import is not a foreground cold-compile stall (refs #100461, salvage #100829)**. merged to main · fix tier `verified`
  - maintainer direction: category `merged`; implication `superseded`
  - files: `tests/tools/test_lazy_deps.py`, `tools/lazy_deps.py`
- **#100505: fix(anthropic): serialize concurrent lazy SDK imports with thread lock (#100461)**. closed without merge
  - maintainer direction: category `uncategorized`; implication `needs_llm`; refs `#100461`, `#100461`
- **#100595: fix(anthropic): serialize concurrent lazy SDK imports (#100461)**. closed without merge
  - maintainer direction: category `duplicate_of`; implication `duplicate`; refs `#100505`, `#100505`
- **#100829: fix(lazy-deps): byte-compile lazily installed backends at install time (#100461)**. closed without merge
  - maintainer direction: category `merged_via`; implication `superseded`; refs `f298911467`, `#100911`

## Fix status

- Merged to main in PR #100911 (cited above). No release data is tracked. Verify downstream.
- Fix last verified (merged) `2026-09-02`.