M6 engine: wave-loop composition per verified design (build only)

[MaxGhenis]

Status: BLOCKED on certified gate-1 forward composition

This is a build-only draft. No M6 temporal-holdout scored run was executed. This branch does not edit gates.yaml, create or modify runs/ artifacts, or modify any frozen file under src/populace_dynamics/models/.

Built

• Ordered annual steps 1-8: mortality, aging/calendar rollover, the single candidate-16 marital core with gate-2c's person-constant earnings-capacity modifier view, fertility/roster, M4 disability, earnings seam, claiming, and candidate-9 household reconciliation.
• Engine-owned (module, period) and stable per-person RNG streams, including injected-generator ports for frozen implementations that otherwise construct their own RNG.
• Candidate-9 step-3 marital-state injection that bypasses its two internal ft.simulate calls and consumes step-4 fertility draws.
• Projection-wide monotone synthetic-person IDs, cross-period marital-state persistence, and DI-conversion propagation into claiming.
• Leakage-safe <= T*=2014 refit entry points with unchanged registry CandidateSpec.sha256 values, no artifact reads/writes, external-vintage validation, and conservative interview-calendar filtering for biennially dated flows.
• Realized-support M4 reproduction mode, projection-horizon clipping, exogenous certified widowhood mode declaration, realized-T* fixed weights, symmetric gated presence-conditioning, and a separate forward-support mode.

Targeted re-certification margin check

PASS on the synthetic fitted-panel test. Injected-state versus candidate-9 internal-simulation output distributions are checked across all required marital-consuming channel sets: cohabitation state/increment, legal core/residual/final-spouse, parental/multigenerational/child/grandchild occupancy, and household-size cells. The check uses the pre-named 3-sigma margin and fails loudly with the design's “fuller re-ceremony required” branch; it was not loosened.

Blocker

The certified gate-1 candidate 11 cannot be composed into the M6 forward annual loop without defining a new stochastic law:

• candidate 11 is byte-identical to candidate 10's backward, biennial imputation chain;
• it holds each person's chronologically latest real earnings as the anchor, predicts t-2 participation from later earnings, and draws earlier ranks from pair/triple/re-entry pools conditioned on later ranks;
• M6 instead starts from realized 2014 and requires annual forward 2015+ earnings.

An adapter would therefore have to make at least three unverified choices: invert the certified backward conditional, extrapolate period-specific marginals beyond the last <=2014 fit cell, and map a two-year kernel to annual steps. It also lacks the future real anchor the certified chain requires. Recursively applying the backward conditional in forward time or fitting an inverse/annual kernel would change the certified spec. Per the lane contract, no such adapter was invented and no frozen implementation was modified.

The branch includes the admissible <=2014 participation-gate refit plumbing, but it intentionally does not claim to produce the complete candidate-11 forward generator. CertifiedEngineInputs therefore still requires an externally supplied earnings generator, and the M6 build cannot be declared complete until this direction/frequency/anchor rule is re-ceremonied.

Design deviations

None were implemented. The gate-1 requirement above remains an explicit blocker rather than an unregistered deviation.

Validation

• M6 synthetic unit suite: 47 passed
• Full always-runnable suite after merging current origin/master: 1,656 passed, 41 skipped, 953 deselected
• Full collection: 2,650 tests
• Tier delta versus current master: unit 225 -> 272 (+47); other tiers unchanged (artifact 905, integration_psid 797, reproduction_legacy 520, oracle_policyengine 156)
• tests/test_tier_policy.py: pass
• Repo-wide Black 79 and Ruff: clean

No M6 gate cell was scored against holdout truth.

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
social-security-model	Ready	Preview, Comment	Jul 13, 2026 4:32am