October 2025 monthly summary for matter-labs/zksync-os: Delivered a focused set of features and reliability improvements to modernize V2 transaction processing, broaden transaction format support, and standardize metadata handling. These workstreams reduce risk, speed reviews, and enable safer, scalable rollouts through improved testing and CI capabilities.

September 2025 (2025-09) monthly summary for matter-labs/zksync-os.成果-focused delivery across cryptographic modeling, transaction encoding, data accounting, reliability, fuzzing, and safeguards. The work delivered improved performance, cost predictability, and resilience, enabling safer production deployments and faster feature delivery.

August 2025 monthly summary for matter-labs repositories (zksync-os and zksync-airbender). Focused on API surface cleanup, correctness and safety improvements, cost accounting refinements, reliability enhancements, and improved observability/diagnostics. Deliverables across the two repos improved API stability, runtime safety, and operational insight while maintaining performance and reproducibility.

July 2025 monthly summary for matter-labs/zksync-os: Delivered a set of performance, reliability, and feature improvements with clear business value, while expanding testing coverage and observability. Key features delivered (business value and technical details): - Performance optimization: switched to musl-libc memcpy/memset and removed no_builtins to boost throughput. Commit ab9f5d1856450d688f59996c04830e25c1824e95 (#119). - Feature flag UX improvements: moved prevrandao under a feature flag to align with config UX; disabled anti-aliasing in default configs for consistency. Commits 8b21bef459edeade5fc2ddd8eeb0ed07fbece875 (#116) and c03f26ebbad86f4f567850d256e4783496e58fb5 (#140). - Native/bytecode enhancements: enabled native charging for bytecode hashing and optimized bytecode preprocessing to improve throughput. Commits 13e8789d71dc124ece6cb461b63ee34526843562 (#137) and 590826a28860aa32f66d7dd0cc35922e4aa4d68c (#125). - API and observability improvements: added helpers for API to encode/decode account data; increased ETH-runner logging; added reporting of native and pubdata in batch output. Commits 75b4ccefb888f0647b6000b5f99e0d622583d410 (#157), c58267905159e749f5d84877a2e019ffd7608344 (#155), and 847bcb370414bcb3e542bc31f45c554e0916d2a9 (#170). - 7702 and protocol hardening: added parsing/hashing support for 7702, implemented 7702 authorization lists logic, enabled EF spec tests for 7702, and enforced block limits to protect network stability. Commits 58505c11efa5d87f74280bdbdc347bfd1680cb1c (#154), 17c72abc05758716be01c41710162d9c40109d65 (#159), 3e027c336b6325710d47c2ea894accda029a12e1 (#164), and 07f18282260b9c28bb008bc450c342f3a3f60b6f (#191). - Reliability and QA enhancements: restored fuzzing in CI, added native charging tests, run EVM tester in release mode, and broadened test coverage for native features. Commits 29e02b982a13be54a2a1d62090fc14048bbd9865 (#136), b48304d3a6e3f4a59cc6fa33312ade1543db43c7 (#141), and 862b7d35416d16a9cd2fa864cbddad3637dd9ffb (#169). - Logging and debug ergonomics: added more ETH runner logs and ensured logs are gated by cycle_marker to avoid unnecessary IO. Commits c58267905159e749f5d84877a2e019ffd7608344 (#155) and 2a9d394e7fa5946d218f4f9013429fa83eced524 (#163). - EVM and gas modeling improvements: EVM gas refunds and constant-native-per-gas modeling in L1 tx simulations to improve fidelity and cost accounting. Commits 00f7abeca48ad631f0ae127d0626c9d7631654ec (#175) and 44c2fb19962333ba235ac4e893845663fee696cb (#167). - Misc fixes for stability: fixes across deployment gas, lazy construction, error handling, and IO paths to harden behavior and reduce flakiness. Representative commits include 953ee44d412e47242bb599bfb0a62c0396cb1694 (#117), c81f8b0d426d800f105fadfee60b7af25ae1d484 (#120), 3b7b0a994cc987c00fd892685208f38d89834717 (#121), 2c1fc4088bc0ace2815857941e2afbe06adb288c (#151), and 0ede60239fe4b5c944551ef649315a350c7370a9 (#173). Major bugs fixed (stability and correctness): - Deployed_in_tx now optional to avoid deployment-time constraints (953ee44d…). - Validate u32 when parsing access lists to ensure correctness (c81f8b0d…). - Include account clears in ref diff (eth-runner) to improve diff fidelity (3b7b0a99…). - Make EE type exhaustive, removing wildcard pitfalls (2c1fc408…). - Taran Phase 3 fixes to stabilize release, tests, and behavior (a4286922…). - Do not log to file unless cycle_marker enabled to spare IO, improve performance (2a9d394e…). - Run EVM tester in release mode for stability and performance (862b7d35…). - Use constant native per gas in L1 tx simulation to stabilize gas accounting (44c2fb19…). - Add interface error for top-level insufficient balance (64db7abd…). - Make try_construct lazy to defer heavy work until necessary (0ede6023…). - Numerous fixes around logging, simulation fidelity, and return data handling (examples: sender of log in base token; simulation closer to execution; increase returndata buffer; exclude withheld from computational; arithmetic oracle fix; intrinsic gas for deployment transactions; usize usage in hooks parsing). Representative commits include 9c5ac24f..., ea065d6d..., 83c4c8cb..., 918fc1c7..., f78616b5..., e4480612..., 80296bba.... Overall impact and accomplishments: - Elevated performance and throughput for critical paths, validated by targeted optimizations and reduced no-ops. - Strengthened reliability and CI coverage with fuzzing, test expansion, and release-mode validation. - Broadened protocol support (7702) and hardened protocol rules (block limits, exhaustive types), improving network stability and future-proofing. - Improved developer productivity and observability through API helpers, richer logs, and batch-output reporting. Technologies and skills demonstrated: - Rust performance tuning and safe concurrency patterns; musl-libc integration; feature flag design for UX consistency. - Advanced testing strategies including fuzzing, CI integration, and release-mode validation. - Protocol engineering for EVM/L1-L2 interplay, 7702 transaction types, and block limits. - Observability enhancements with logging controls and API data-encoding utilities. Repository: matter-labs/zksync-os (July 2025)

June 2025 monthly summary for matter-labs/zksync-os: Focused on stabilizing the runtime, expanding access-list capabilities, and improving build reliability. Delivered key features around access-list handling, introduced double accounting, and updated storage/transaction encoding, with multiple bug fixes improving correctness and performance. These changes enhance block processing fidelity, gas accounting accuracy, and system reliability, while laying groundwork for upcoming optimizations and feature work.

Monthly Summary for May 2025 (Matter Labs). This period focused on delivering cost accounting enhancements, expanding transaction capabilities, and improving reliability and observability across two repositories: zksync-os and zksync-airbender. The work enhanced business value while strengthening technical foundations for pricing, security, and performance.