← All cases · Knowledge unlocked · prototype · since August 2026
Spec to running app in eight person-days
Eight functional and domain building blocks with around 160 input fields in about eight person-days; requirements become visible as running features immediately and can be reviewed by experts right away.
Figure: ≈ rund 8 Personentage vom Fachkonzept zur lauffähigen App · estimate
Request: „Turn the functional spec for a tax valuation procedure into a running app — calculation core, wizard and official forms included.“
- The AI reads the functional spec plus the tax and legacy-system knowledge stored in the Business Brain
- It builds the calculation core, plausibility rules and a guided step-by-step wizard
- It migrates calculation cases from the legacy system almost without manual work and auto-fills the official forms
- It connects an official data service and renders results with the underlying tax reasoning
- Save and load, export of the semantic data model and smoke tests in the browser round off the prototype
A functional spec gets written, handed over, scheduled and becomes visible as a first feature weeks later — the usual route in any software organisation.
Precise requirements and the expert quality review — especially at the edges of the tax logic. A comprehensive QA of the prototype is still open.
At the edges of the tax logic and with specific requirements, the AI only delivers robust results once the definition is precise — without it, output is plausible but not correct.
Any organisation with a legacy system and 15+ years of embedded domain knowledge: the lever is automatically merging the old and new worlds during migration.
A domain expert wanted to know how far a Business Brain loaded with tax knowledge would carry. He took the functional spec for a tax valuation procedure and had the AI build an app: calculation core with plausibility rules, guided data entry with a wizard, auto-filled official forms, a connection to an official data service, results with the underlying tax reasoning. Eight building blocks, about eight person-days. The lever was the legacy system: calculation cases from over 15 years of domain development were migrated almost without manual work. What mattered was less the speed than the success factor behind it: precise requirements and expert QA, not the prompt. The prototype runs locally in the browser and has spread to first teams; a second one for searching historical tax data runs on synthetic demo data in the company design system. A full QA is still open.
Evidence in my own archive · as of 25 October 2026.