June 2025 Monthly Summary for risc0/risc0-ethereum: Key delivered feature: - CI Cluster-based Runner Migration: Migrated CI environment from a production runner to a cluster-based runner across multiple GitHub Actions workflows, with updates to hardware configurations and CUDA-related environment variables to leverage the cluster CI infrastructure for improved build and test execution. Major bugs fixed: - None documented for this period. Focus remained on CI infrastructure modernization and stability. Overall impact and accomplishments: - Achieved scalable, more reliable CI for risc0/risc0-ethereum, enabling faster feedback on PRs and more consistent build/test results across workflows. - Positioned the repo for greater CI throughput and resource efficiency through cluster-based runners and updated environment configurations. Technologies/skills demonstrated: - GitHub Actions workflows orchestration and migration planning - Cluster-based CI infrastructure adoption - Hardware configuration tuning and CUDA environment variable management - Change control and documentation alignment with WEB3-462 initiative - Cross-repo collaboration and traceability via commit references (ab2fdafac60327e310121ada9e65bce8a439fba2)

March 2025: Explored GPU-accelerated cryptography in risc0/risc0 by prototyping CUDA-enabled Blst integration. Implemented scaffolding and conditional build wiring (build.rs, Cargo.toml) to enable Blst when CUDA is active, and wired Blst C sources for potential CUDA kernel compilation. The experimental changes were reverted to preserve build stability, with documentation and rationale recorded to support future decisions. This work establishes a baseline for evaluating performance gains from GPU-accelerated cryptography while maintaining reliability of the main branch.