Custom AI software development, from MVP to production SLA
We build products where AI is part of the workflow, not a bolt-on. It is the same stack we use to run our own Happ platform in production.
This category covers full product engineering: AI MVPs, turnkey custom software, web portals, mobile apps, SaaS products, legacy modernization and dedicated teams. AI is one part of the product. Around it there is always a backend, a database, roles, integrations and monitoring.
It pays off when off-the-shelf tools do not fit your process, or when the software is the business itself. It also pays off when an old system slows everyone down but cannot be switched off. If a ready Happ agent solves the task, we will tell you and skip the custom build.
We build and run the Happ platform ourselves: NestJS, Next.js, a React Native and Expo app in the App Store and Google Play, PostgreSQL, Temporal and our own vLLM. Client projects follow the same process: 1-2 weeks of discovery, a fixed estimate in 2-3 days, weekly demos, launch on part of traffic, then SLA support.
Services in this section
- from $15,000 · 6–12 weeksAI MVP development
AI MVP development that gets you in front of paying customers. One core scenario done properly: sign up, payment or request, the AI feature, analytics. No months spent on features nobody asked for.
Details → - from $15,000 · 8–20 weeksCustom software development services
Custom software development for the moment spreadsheets and SaaS tools stop holding your process together. We build the system around how your team works and add AI only where it actually saves time.
Details → - from $10,000 · 8–16 weeksWeb platform and portal development
Web platform development for the place your customers, partners or staff log into every day. A portal with statuses, documents and payments instead of calls to an account manager and chat threads.
Details → - from $15,000 · 10–20 weeksAI mobile app development
AI mobile app development on React Native and Expo: one codebase for iOS and Android. Our own Happ app is live in the App Store and Google Play, so we take builds from code to store review all the time.
Details → - from $15,000 · 10–20 weeksLegacy system modernization
Legacy system modernization in pieces while the old system keeps running. First we put a new API layer next to it, then move module by module, and switch the old part off only once the new one is proven.
Details → - from $20,000 · 12–24 weeksSaaS product development
SaaS product development that keeps working as your customer base grows, with no rewrite after the first sales. We build and run the Happ SaaS platform ourselves, with companies, plans and AI agents, so we know where these products break.
Details → - from $10,000/mo · 12–52 weeksDedicated development team
A dedicated development team that works only on your product. The team lead owns the process and the result, engineers write code and tests, QA checks every release. Billed monthly, from $10,000 per month.
Details → - from $10,000 · 6–12 weeksAI prototype to production
Taking an AI prototype to production when it shines in demos but fails under real load. We audit, harden and launch it on part of traffic, then keep it running under an SLA.
Details →
All services
Describe the task. The first call is with the founder.
We reply within one business day. 30 minutes to tell you whether it is worth doing and what it costs.