February 2026: Implemented Comment Encoding Standardization (UTF-8) across acl2/acl2 to improve cross-locale readability and compatibility. The change is comment-only, non-semantic, converting a non-ASCII byte in axioms.lisp from ISO-8859-1 to UTF-8 (commit 4784ab6996f74d460c127c102534e5d73099ad7f).

Month: 2025-10. All-Hands-AI/agent-sdk delivered a new Optional Security Analyzer for the Default Agent Configuration, enabling opt-in security analysis via an environment variable. This change adds a configurable security analysis path without impacting existing deployments, supporting security audits and risk assessment while maintaining backward compatibility. The update aligns with a security-by-default posture and reduces deployment risk by allowing teams to opt in to analysis as needed.