January 2026 monthly summary for astral-sh/ruff focusing on improving type resolution fidelity for subclass scenarios involving classmethods decorated with context managers. Implemented a fix so return types resolve to the correct subclass (Self) when accessed on derived classes, and added accompanying tests for base and child classes to ensure long-term reliability. Updated tests (mdtests) to cover the new behavior and documented the change path for ongoing Self/typing improvements. This work enhances type safety, developer experience, and confidence in Ruff’s type checker for factory-like patterns using classmethods with context managers. Related to ongoing efforts to stabilize TypeVar/Self handling (issue referenced in PR).

January 2025 monthly summary for ndmitchell/ruff. Focused on a targeted quality improvement to preserve the integrity of linting results in the ecosystem. Implemented a change to disable automatic fixes within ruff-ecosystem checks so checks only report violations, avoiding automated changes that could pollute results. This aligns with best practices for observable, auditable code quality and reduces noise in CI feedback. Commits related to this change: bafe8714a809383487167b27d119ce1ce36a2e46 with message 'Don't fix in ecosystem check (#15267)'.