One document from which a third party can implement a client that follows chain
2800 without reading our code: chain parameters, QBFT with the full extraData
layout and what the block hash does and does not cover, the post-quantum anchor
rules with exact pre-images and the follower configuration, precompile formats
with the message in the middle and variable signature lengths, fee rules with
their historical windows, sync requirements including the genesis-set ceiling,
and the formal models with their honest boundaries.
Every normative statement carries a file citation, a [MEASURED <date>] marker
with the command, or [NOT MEASURED]. Section 8 documents twelve dated
divergences a syncing client will meet on the real chain (the 2138451 transition
value that must not be corrected, the base-fee lapse window, the anchor disarmed
window, the threshold window, the retired falcon.forkBlock rule), because a spec
that hides history cannot sync anyone. Section 9 lists ten things this spec
cannot state from published sources, by name, rather than papering over them.
