The Suite

Courant Regress

In developmentOctober 2026

What it runs on
Your whole case library, nightly
What it decides
Drift from the accepted baseline
Cost of being wrong
A regression found at review, not at commit

What it checksCriterion

  1. 01
    Drift from baseline

    The quantity you care about, compared with the run you signed off.

    per-case tolerance you set
  2. 02
    Silent change of regime

    A case that still converges, into a different answer than last month.

    same inputs, different physics
  3. 03
    Environment moved

    The run did not change. What ran it did.

    solver build, decomposition, libraries

These are criteria, not results. Nothing here has been measured — the product is not built.

What comes back

  • The cause, and the line of solver output it came from
  • The change, as a diff you can reverse
  • Physics checks, measured against their limits
  • A record somebody else can open on a link

Targets

  • Every product in the suite
  • Your CI
  • The same evidence record

Named as intent. No adapter for any of these exists today.

Standing

In development, targeted at October 2026. It is the layer over the other four rather than a physics of its own: the same watch-diagnose-verify loop, run on a schedule over a library of cases instead of once over one.