Whole software,no fractions.
integer3 designs, builds and runs custom software, AI agents and cloud platforms for teams that need the whole thing to work.
We design 
the product, build 
the platform, wire in 
the agents and run 
it, as one team.
What we build
Custom Software & SaaS
Multi-tenant SaaS platforms and internal systems, designed with your users and built to be run for years.
Product discovery, UI/UX design, Multi-tenant architecture, Billing and subscriptions, QA and test automation
Read about Custom Software & SaaS
From brief to live
- Discover. First, we map users, data and risks.Discover. First, we pick one workflow and its data.Discover. First, audiences, platforms and scope.Discover. First, an audit of what runs where.
- Design. Then flows and UI, tested with users.Design. Then tools, guardrails and evaluations.Design. Then prototypes on real phones.Design. Then the target architecture and costs.
- Build. Next, two-week releases to staging.Build. Next, a pilot with real users.Build. Next, weekly test builds.Build. Next, move service by service.
- Scale. Finally, launch, measure and grow.Scale. Finally, more workflows, measured.Scale. Finally, store launch and updates.Scale. Finally, on-call, tuning and savings.
Typical durations from discovery call to launch. Your project gets its own plan.
Agents that ask first.
“Hi, my order A-1187 arrived damaged. Can I get a refund?”
search_orders(id: "A-1187")Delivered 12 days ago · €84.00 · cardcheck_policy("damaged_on_arrival")Eligible: full refund within 30 daysissue_refund(amount: 84.00)Needs approval: refunds over €50ApproveEditReject
Every tool call is logged, every risky step waits for a person, and every run can be replayed.
Tools we stand behind
| Area | Tool | What for |
|---|---|---|
| Front end | React | Web Application |
| TypeScript | One typed language from database to browser | |
| Next.js | Web apps and sites, rendered at the edge | |
| Mobile | Kotlin | Android Mobile Application |
| React Native | iOS and Android from one codebase | |
| Back end | Node.js | APIs, workers and integrations |
| GraphQL | Typed APIs between every client and server | |
| AI | Python | Data pipelines and model tooling |
| Anthropic Claude | Reasoning and tool use inside agents | |
| pgvector | Search over your own documents | |
| Data | PostgreSQL | The system of record |
| Redis | Queues, caching and rate limits | |
| Cloud | AWS | Compute, storage and networking |
| Vercel | Serverless hosting for web front ends | |
| Terraform | Infrastructure defined as reviewed code | |
| Docker | Identical builds from laptop to production | |
| Quality | GitHub Actions | Tests and deploys on every change |
| Playwright | End-to-end and accessibility tests | |
| Sentry | Errors and performance in production |
Questions before we start
How do projects start?
With a 30-minute call about the problem, then a short paid discovery that ends in a written plan, a timeline and a fixed quote for the first release.
Who owns the code?
You do. Code, designs and infrastructure are in your accounts from day one, and the intellectual property transfers to you on payment.
How do you price work?
Fixed price for a defined first release, or a monthly fee for a dedicated team. We share the estimate before any work begins.
How will we know how it's going?
You get a working staging environment from the second week, a short written update every Friday and a demo every two weeks.
What happens after launch?
We can run and improve the product on a monthly plan, or hand it over with documentation and runbooks so your team can take it on.
Can you work with our existing team?
Yes. We often join an in-house team, follow its practices and leave behind tests, docs and knowledge rather than a dependency on us.
Start a project
A person replies within one working day. Prefer detail? Use the full brief form.