June 2025 monthly summary for tact-lang/tact. Key features delivered: - Implemented Message Sequence Number (seqno) validation in the message processing path to prevent replay attacks. The runtime check enforces that incoming messages have msg.seqno equal to self.seqno before processing, strengthening message integrity. - Updated security best practices documentation to reflect the new seqno validation (commit referenced). Major bugs fixed: - Security vulnerability addressed by adding runtime seqno validation; message acceptance now guarded by seqno equality, mitigating replay and tampering risks. Overall impact and accomplishments: - Strengthened security posture of the messaging subsystem, reducing risk of replay attacks and ensuring message integrity. - Documentation alignment with security enhancements improves developer guidance and compliance. - Demonstrated end-to-end delivery, including code changes and docs updates, with traceable commits. Technologies/skills demonstrated: - Security-focused development, runtime input validation, and secure messaging patterns. - Documentation and changelog discipline with traceability to commits (#3323). - Cross-functional collaboration between code and documentation to deliver a cohesive security improvement.

May 2025 monthly summary for informalsystems/quint: Documentation improvements focused on user navigation and accuracy. Delivered two targeted fixes that correct README links and remove a duplicate language manual entry, improving onboarding, reducing confusion, and aligning docs with current product behavior. No code features released this month; changes enhance user experience and support efficiency.