Case study · Nexxt Nest Group
A live SaaS that turns a builder's site notes into the documents the law and their cashflow depend on, with real subscription billing behind it.
Victorian builders spend their evenings producing documents their cashflow depends on: Security of Payment Act progress claims, WorkSafe-format SWMS, site diaries, variations, quotes. A progress claim done properly takes hours; done badly, it can cost the builder an adjudication.
Seventeen AI-powered tools: SOP Act–formatted progress claims from raw notes in about a minute, SWMS generation, a voice-capable site diary, a defect & variation log that turns issues into formal variation orders, a plan reader that lets a builder interrogate a drawing set, a quote generator seeded with Victorian trade rates, a subcontractor register with licence and insurance expiry alerts, extension-of-time notices, and a daily supervisor brief.
Grounding. An AI that invents a contract sum is worse than useless, so every AI call runs through a server-side context assembler that grounds the model in that project's live data, and every output carries advisory-only framing.
The reactive engine. Site-diary weather delays automatically build the evidentiary basis for extension-of-time notices, and a build-stage model predicts obligations forward — "it's coming," not "you missed it."
Real commerce. This isn't a demo: Stripe subscriptions run live, with webhook reconciliation and entitlements enforced server-side, so a cancelled card actually downgrades the account.
Job sites have no signal. Field capture is offline-first with automatic sync when reception returns.
A hand-written Content-Security-Policy with a live violation-report endpoint, HSTS, row-level-security tenant isolation, server-side entitlement checks on every AI route, daily request caps and rate limiting — plus four production cron jobs for the daily briefs and compliance digests. Roughly 20,000 lines of code, 300+ commits and an automated test suite.
The product is its own demo: sign up on the free tier, with no card — and generate a formatted progress claim in about sixty seconds. The site deliberately shows no testimonials; the placeholder literally says we'd rather show nothing than make them up.
I can ship a complete commercial SaaS alone — product design, AI integration that respects a regulated domain, real payments, scheduled operations and security hardening, and keep it running.