August 2025: Strengthened nftables/netfilter capabilities across SagerNet/gvisor and google/gvisor, delivering core features for policy-driven network filtering, batch updates, and robust test infrastructure. Key outcomes include NFTables NEW_RULE implementation with validation groundwork; NETLINK batch messaging and atomic batch operations; protocol integration for IPv4/IPv6 with DUMP/GETRULE and nested attribute handling; centralized test utilities and Docker-based testing; and diligent TODO bug-ID maintenance to reduce debt. These efforts improve deployment confidence, reduce MTTR for policy changes, and enhance CI reliability.

Concise monthly summary for 2025-07 focusing on NFTables enhancements in SagerNet/gvisor, with emphasis on business value, reliability, and testability. Delivered feature-rich NFTables lifecycle, chain management, and rule handle support, alongside concurrency and socket reliability improvements and a strengthened testing framework.

June 2025 monthly summary for SagerNet/gvisor focused on delivering NFTables Netlink Netfilter integration in runsc, establishing a foundation for policy-driven network filtering within the sandboxed runtime. Achievements include groundwork for Netlink Netfilter sockets, a modular nftables package, integration with the tcpip/stack, and a gating flag to isolate NETLINK_NETFILTER behavior. The work also delivered table operations support, enhanced error handling with POSIX syserr errors, and progressive refactors that simplify maintenance and enable broader use across the stack.