March 2026 — Hermes-3 (boutproject/hermes-3) focused on correctness and stability improvements in potential calculations by refining boundary condition handling in the relax_potential routine. This work enhances numerical accuracy and reliability of simulations with minimal risk of regression elsewhere.

January 2026 (2026-01) monthly summary for boutproject/hermes-3. Highlights two major feature updates that deliver business value and enhance simulation fidelity: 1) Neutral Transport Coefficients Calculation with optional constant coefficients for neutral fluid; 2) Relax_potential Component Overhaul with vorticity integration and enhanced boundary handling.

December 2025 monthly summary for boutproject/hermes-3: Key feature delivered: Vorticity Calculation Performance Optimization by precomputing Grad(phi) to avoid repeated calculations for every species. This change reduces per-species gradient recomputation, improving vorticity calculation performance and enabling larger simulations. Major bugs fixed: None reported this month. Overall impact: significantly improved runtime efficiency and scalability of vorticity calculations, delivering tangible throughput gains for multi-species runs and reducing compute costs. Technologies/skills demonstrated: performance optimization, caching/precomputation strategies, code profiling and instrumentation, and clear commit-based traceability (linked to commit de487f833448dcce814aad0dcef63055c05d42ef).

In July 2025, the BOUT-dev SNES solver benefited from two core feature enhancements and several stability/quality improvements, delivering business value through faster, more stable, and scalable simulations for large-scale runs. The adaptive timestep capability, implemented via a PID controller for the backward Euler SNES solver, improves stability and efficiency. Memory optimizations and parallel performance enhancements preserve the Jacobian non-zero pattern and adopt greedy coloring to boost scalability on large parallel workloads. Complementary maintenance work focused on consistency and code quality, ensuring robust future iterations.