Most AI accounting tools let a language model write numbers into your books. Felix doesn't. Under the §0.1 architecture, the AI only proposes; a deterministic ledger computes every figure; and a validator rejects anything not backed by a journal line.
That means Felix is fast like AI and trustworthy like arithmetic: a categorization can be smart, but a balance can never be invented. If a number appears in Felix, there is a journal line — traceable to a real bank transaction — behind it.
This page explains the architecture end to end: the proposer, the deterministic engine, the validator, and the audit trail that ties every figure back to source data.