Principles that govern every product
These principles are design rules. Each one is reflected in how the software is built, tested, and released.
- Primary sources first
- Answers are drawn from legislation, rulings, judgments, and accounting standards retrieved from authoritative sources, and each proposition carries the source it rests on.
- Rules before models
- Whether a provision exists, whether it was in force for the period, and whether quoted text matches the official compilation are settled by deterministic checks. Models are used where a task cannot be reduced to a rule, and their output is presented for a professional to review.
- Closed on policy, open on evidence
- A control that governs whether an answer may be given fails closed, and the system declines before it guesses. A check that only adds evidence degrades quietly and reports that it did.
- Measured before it is claimed
- No accuracy, speed, or time-saving figure is published until it has been measured on real work, and every figure is stated with its sample size.
- Law held as versioned data
- Rates, thresholds, and statutory parameters are held as dated records with a verification status. A change in the law is therefore loaded as data, and every past result can be reproduced.
- The professional remains responsible
- Our software supports the judgement of the professional who signs the work. It does not provide legal, tax, or accounting advice.