2026-01-08 Engineering Team

[joecastiglione]

Agenda

• Progress on Closing Tasks
• Status of UV install review with partners

Notes

Attendees: Jeff Newman, David Hensle, Sijia Wang, Stefan Coe, Joe Flood, Jilan Chen , Ray Ngo, Joe Castiglione

1. Logistics

• Joe Flood noted he is departing in approximately three weeks (flying out the 29th, move-in on the 31st). A farewell gathering is being coordinated via a Doodle poll; the Zephyr Foundation representative was inadvertently left off the distribution list and asked to be included.

2. Phase 11 Checklist Review

• Jeff Newman led a walkthrough of recent pull requests.
• RSG – Shadow Pricing Zone Fix: Jeff confirmed the fix works and passes all tests. The only requested change is adding a changelog note, since the update may produce marginally non-identical results for reproducible random seeds. David confirmed he would add the note.
• Capitalization Fix (alts): A separate RSG pull request addressing capitalization inconsistencies in "alts" references was reviewed, repaired (a file corruption issue was resolved by Jeff), and merged.

3. Skip-Household Feature (Sijia / WSP)

• Jeff reviewed the WSP pull request implementing a global option to skip failing households during simulation runs.
• Key design decisions: The feature is implemented as a single global switch — not component-level — which keeps configuration clean and reduces the risk of forgotten per-component overrides. It allows a modest number of household failures to be skipped and logged, but raises an error if failures exceed a significant fraction of total households, preventing silently degraded runs.
• Skipped household IDs are logged at warning/error level, and prior checkpoints retain skipped households; removal only applies to downstream processing from the point of failure onward.
• Logging enhancements: The team agreed a summary table showing households skipped by component would be a useful addition. Sijia confirmed she would implement this. Jeff also noted this tracking could serve as the mechanism to optimize redundant filtering passes (addressing an existing code to-do).
• Estimation mode: The current whole-household removal approach is appropriate for simulation mode. More nuanced handling for estimation mode is out of scope for the current WSP task but flagged for future consideration.
  Sijia's next steps: Address Jeff's review comments and add the by-component skip summary table.

4. UV Environment Update

• Jeff reported strong results with the new UV dependency management system. Cloning the repository in a fresh directory now works out of the box in VS Code and PyCharm with no manual environment setup.
• Agency feedback:
  • SEMCOG: Testing went well; will open to additional modelers.
  • MWCOG: UV and ActivitySim 1.5.1 integrated into current model. Cloud and on-prem testing positive; some uncertainty around client-side restrictions remains. UV with ITVCC 1.5.1 is not yet working — assessed as a Sharrow issue, not UV.
  • NSW: On holiday; Sijia will follow up next week.
  • CMAP: Has not yet tested; hoping to do so in February.
  • Met Council: Not yet ready to test (RSG's remaining open item).
• Task completion: The group agreed 100% agency adoption is not required to declare success. All agencies that have tested with the revised instructions reported success. Jeff recommended the product/executive team formally ratify completion; Zephyr Foundation concurred. Sijia confirmed second-round outreach has been completed with SAMCOG, MWCOG, NSW, ARC, and CMAP.

5. Wrap-Up

A few remaining items outside Phase 11C scope will be addressed once current PRs are resolved. No additional topics were raised. The team is near the close of Phase 11B, with Phase 11C anticipated in the near future.
Meeting adjourned early — approximately 30 minutes returned to attendees.