June 2025 performance for scroll-tech/ceno focused on code quality and maintainability, with a targeted refactor to RNG usage. Delivered an explicit RNG usage pattern to resolve rustfmt warnings across multiple modules, improving readability and correctness. No major user-facing features added this month; the focus was a stable, high-quality codebase and groundwork for future RNG improvements.

May 2025 focused on delivering distributed Hyrax enhancements in PolyhedraZK/Expander to improve performance and correctness of polynomial commitments in MPI environments. Implemented pedersen_vars handling across MPI and local variables to ensure correct setup and commitment generation, and added scatter_vec in the MPI engine to correctly distribute data from the root process to all processes with proper chunking and role-based distribution. Added tests for MPI distribution paths to validate correctness and reliability. This work establishes a foundation for scalable commitments in larger clusters and improves overall system reliability.

April 2025 monthly summary for PolyhedraZK/Expander: Delivered foundational MPI-based capabilities for Orion matrix transpose and PCS utilities, improved bit-level correctness for GF2x SIMD operations, expanded FFT capabilities across Goldilocks extensions and babybear with benchmarking, and pursued performance-oriented optimizations while maintaining CI stability. Concurrently performed code cleanup and dependency simplification to reduce maintenance and build complexity, paving the way for scalable cryptographic workloads and faster iteration cycles.

For 2025-03, PolyhedraZK/Expander delivered a set of cryptographic feature enhancements, performance optimizations, and CI/stability improvements that strengthen reliability, scalability, and business value of the proof system. Key features include Fiat-Shamir transcript robustness with updated dependencies and CI workflows; PCS core verification simplification with edge-case handling and polynomial padding; Orion PCS performance optimizations to reduce redundant transpositions; Multilinear KZG PCS integration with config updates and benchmarking; and arithmetic library enhancements including SIMD-based horizontal sum, FFT-based univariate polynomial capabilities on BN254 Fr, plus test RNG simplification for PCS. These changes reduce verification overhead, improve cryptographic reliability, and support scalable proof generation across Expander/GKR workflows. Major bug fixes included removing MPI from the PCS verification path to reduce flakiness, padding polynomials for short inputs to prevent verification failures, and API stabilization for PCSForExpander trait; and test robustness improvements by using system RNG. Overall impact: faster proof generation and verification, more robust cryptographic primitives, easier maintenance, and stronger CI stability.

February 2025 monthly summary for PolyhedraZK/Expander focused on feature delivery, dependency cleanup, and cryptographic-PCS integrations to enable production readiness. Delivered end-to-end configuration and persistence scaffolding for new PCS schemes, improved build stability by removing unused parallel dependencies, and enhanced serialization paths to support new configuration options and scratch pads.

January 2025 performance summary for PolyhedraZK development efforts across Expander and ExpanderCompilerCollection. Delivered high-value features focused on secure, scalable hashing and commitment schemes, cross-field recursion, and reliable build/deployment pipelines. The month emphasized business impact through faster cryptographic operations, cross-field recursive proofs, and improved CI reliability.

December 2024 was focused on strengthening the Expander's field arithmetic, polynomial commitment system (PCS), and test reliability. Key work delivered in PolyhedraZK/Expander included extension-field conversion utilities, a refactor to support multilinear polynomial traits in PCS, deterministic RNG seeding for MPI-based testing to ensure reproducible CRS, and a BN254 RawPCS deserialization bug fix along with a new RawCommitment struct. These changes improve modularity, test determinism, and robustness of commitments, ultimately supporting more reliable zero-knowledge proofs and easier extension field support.

November 2024 monthly summary for PolyhedraZK/Expander focused on performance, reliability, and architectural improvements for Orion PCS. Delivered SIMD-accelerated GF2x arithmetic to boost field operations, added a Merkle Tree data structure with serialization to enable scalable proofs, simplified serialization APIs for maintainability, and completed targeted quality improvements including typo fixes and CI/benchmark cleanup. These efforts together improved computation throughput for zk operations, reduced integration friction, and strengthened the codebase for future scalability.