Custom AI apps built around how your business actually works
A custom AI app is software built for one business's specific process, with AI features such as search over your own documents, document reading, or drafting built in. FIT builds them when off-the-shelf tools don't fit, keeping them small, secure and owned by you.
What you get
- A short product brief covering the users, the job the app does, what success looks like, and what's out of scope.
- A clickable prototype you can test with real users before full build.
- The production app, with login, roles and an audit log where needed.
- Retrieval-augmented generation (RAG) over your documents, with citations so users can check every answer.
- Hosting on infrastructure you own (Cloudflare, AWS, Google Cloud or Azure), plus a cost estimate.
- Source code, documentation and a handover session.
Examples
Internal knowledge assistant
Document intake and review
Client portal with AI help
Small, specific and owned by you
Custom software fails when it tries to do everything. We build the smallest app that does one valuable job well, put it in front of real users quickly, and grow it based on what they actually use.
How we build
- Prototype first. You click through a working prototype within the first couple of weeks, before committing to the full build.
- Security from day one. Login, role-based access, encrypted data, audit logs for sensitive actions and least-privilege API keys.
- Answers you can check. Any AI answer that could influence a decision shows its source. Where accuracy matters, a human approves before anything is sent or saved.
- Running costs you can predict. We estimate model and hosting costs per user or per document before we build, and design to keep them low (for example by caching, using smaller models for simple steps, and only calling AI when needed).
Typical tools
Astro / React / Next.js · Cloudflare Workers & D1 · Supabase / Postgres · Vector search · OpenAI / Anthropic Claude / open models · Document AI / OCR
Typical timeline
Prototype in 1–2 weeks. A focused first version of the app typically ships in 4–10 weeks, depending on integrations and security requirements.
Frequently asked questions
When should I build a custom AI app instead of buying software?
Build when your process is a real competitive advantage, when no existing product fits without heavy workarounds, or when you need control over where sensitive data goes. Buy when a well-supported product already does 80% of what you need. We will tell you honestly if buying is the better option.
What is RAG (retrieval-augmented generation)?
RAG is a technique where the AI first searches your own documents for relevant passages and then writes its answer using only those passages, usually with citations. It reduces made-up answers and keeps the AI's knowledge current without retraining a model.
Is my data used to train AI models?
Not by us. We use AI providers' business or API terms that exclude customer data from model training, and we can use models hosted in a specific region or on your own infrastructure when required.
Do I own the code?
Yes. Unless we agree otherwise in writing, you own the code and the deployed app, and it runs in accounts you control.
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