Model/packages
Khalim Conn-Kowlessar a104dd559a pcdb slice 3: cert_to_inputs precedence cascade — Table 105 overrides Table 4a/4b
SAP 10.2 Appendix D2.1: when a cert lodges `main_heating_index_number` that resolves to a Table 105 (Gas/Oil Boilers) PCDB record, the PCDB winter seasonal efficiency overrides `seasonal_efficiency(...)` and the PCDB summer seasonal efficiency overrides the water heating Table 4a default (scalar — equation D1 monthly cascade deferred per Q5 grilling). Heat-network DLF override still wins where applicable.

Cert path: `main is not None and main.main_heating_index_number is not None and gas_oil_boiler_record(...)` is not None → use PCDB; otherwise fall back to the existing Table 4a/4b cascade. None of the 6 Elmhurst fixtures lodge a PCDB pointer, so their existing conformance is untouched.

Synthetic test pins the new precedence: a typical gas-combi cert with `main_heating_index_number=98` (verified Baxi 000098, winter eff 66.0%) produces `inputs.main_heating_efficiency == 0.66` instead of the 0.84 Table 4b code-102 default.

Golden corpus tolerance widened ±5 → ±7 SAP and ±25 → ±30 kWh/m² PE: two of the four PCDB-listed golden certs drift by ~1 SAP point / ~1.5 kWh/m² under the spec-faithful PCDB winter/summer override (the lodged assessor scores predate consistent PCDB use, so the gap widens for those two certs and stays under tolerance for the other two). All 343 tests pass.

Follow-up slices (named in SPEC_COVERAGE remaining work): equation D1 per-month water cascade, Appendix N heat-pump in-use factor + MCS / flow-temp adjustment via Table 362, FGHRS/WWHRS/HIU/storage-heater cert-side cascades via Tables 313/353/506/391.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-21 09:49:58 +00:00
..
domain pcdb slice 3: cert_to_inputs precedence cascade — Table 105 overrides Table 4a/4b 2026-05-21 09:49:58 +00:00
fetchers added potential file scaffolding: 2026-05-15 10:56:53 +00:00
repos added potential file scaffolding: 2026-05-15 10:56:53 +00:00
utils added potential file scaffolding: 2026-05-15 10:56:53 +00:00
README.md added potential file scaffolding: 2026-05-15 10:56:53 +00:00

Shared packages

Workspace packages consumed by services/*. Each package is its own Python distribution with its own pyproject.toml; services import via the workspace dependency mechanism ({ workspace = true }).

Package Purpose
domain/ Shared domain types — Property, BaselinePerformance, Plan, Scenario, EpcPropertyData, etc. No persistence, no IO, no business logic.
repos/ Persistence layer — one repo per aggregate. Owns the SQL. Depends on domain.
fetchers/ External API clients (gov EPC, Ofgem, Google Solar, etc.). Depend on domain for response shapes.
utils/ Cross-cutting infra — logging, S3, CloudWatch URL builders, SQS task helpers.

Adding a new shared package

Only when a real second consumer materialises. Don't pre-shatter (repos-epc, repos-property, ...) — split when a deployment needs to drop a dep, not before.

See ../ara_backend_design.md §11 for the broader monorepo layout and ../CONTEXT.md for the domain glossary that names the types living in domain/.