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Build ledger · public

Status & coverage

A live account of what is built, what is verified, and whether the full canon is worth committing to. Every number below traces to a gate that either passes or blocks the build.

20
derivations verified
3
units seeded
58
inbound lecture links
G0
gate on schema freeze

Quality gates

Gates run in order. A downstream gate is meaningless until every gate above it is green, so the ledger blocks rather than warns.

G0
Schema freeze
derivation record fields fixed: id · statement · assumptions · steps · result · used_by
pass
G1
Units — dimensional check parses
every result equation reduces to consistent SI dimensions
pass
G2
Numeric — verified to 4 s.f.
worked value reproduced from first principles, agrees to four significant figures
pass
G3
Provenance — authored independently
each derivation written from the physics, not transcribed; sources cited for cross-check only
pass
G4
Links — every used_by resolves, no orphans
each lecture cite points to a live derivation; each derivation is reachable from at least one unit
pass

Cost probe

why 20 first

Measuring the real cost of one page

These 20 derivations are not a sample of the canon — they are a stopwatch. Each is built end-to-end through all four gates so we record actual hours-per-page before committing to the full ~410-page canon.

The pilot spans three units and eight threads so the average reflects hard pages, not just the easy ones.

the decision

What the mean buys us

under 3h mean two-year project viable The full canon is affordable at a sustainable pace; proceed to seed the remaining units.

over 8h mean cut to a 150-derivation core The canon as scoped is too expensive; drop to a tighter core that still spans every thread.

Between 3h and 8h the call is a judgement, not a rule: re-scope per-thread, or trade rigour tier depth against coverage. This band is where the probe earns its keep.

Permalink · see the method, the derivation vault, or a worked example at D-001.