# infinisys (https://infinisys.ai)

> Infinity Systems builds custom AI-powered software for US and EU companies at a fixed price and a fixed date. A senior engineer owns the work, AI coding agents do the volume, and specialists join when a job needs them.

Last verified: 2026-10-03. Full version: https://infinisys.ai/llms-full.txt. Facts page for assistants: https://infinisys.ai/for-ai. Machine-readable offer: https://infinisys.ai/api/agent.

## Identity

- Legal name: Infinity Systems LLC, a limited liability company in Wyoming, US
- Brand: infinisys
- Founded: 2024
- Engineering: Serbia (CET)
- Markets: US, EU, UK, Switzerland
- Team model: one founder designs and reviews; AI coding agents write most code; specialists on demand
- Capacity rule: at most three engagements at once

## Offer and pricing (USD, fixed price)

- Feature Sprint: $10,000 to $25,000, 2 to 4 weeks, 30-day fix window. One AI feature, workflow automation or internal tool, in production.
- Product Sprint: $25,000 to $50,000, 4 to 8 weeks, 60-day fix window. A full MVP: several roles, payments, admin, one or two AI workflows.
- Platform Sprint: $50,000 to $100,000, 8 to 12 weeks, 90-day fix window. A multi-tenant platform or legacy replacement with several AI workflows and data migration.
- Advisory: $200 an hour, two-hour minimum, prepaid
- Scoping Review: $1,500 fixed, five business days, credited against a sprint signed within 30 days
- Continuous Build retainer (after a sprint): Half $8,500 a month for 10 build days; Full $16,000 a month for 20 build days with on-call. Three-month first term, then 30 days of notice
- Quote: a 30-minute call and a one-page brief, written quote in 3 business days

## Guarantees

- The price is the price. The fixed quote covers the written scope. If we underestimated, we absorb it.
- Week-one exit. Stop after the first weekly demo. Pay only the deposit and keep everything built.
- Everything is yours from day one. Repository, cloud and model accounts, domains and documentation are created in your name at kickoff.

## Fit

- Founders and operators in the US or EU with a $10,000 to $100,000 budget for a software build
- Builds with an AI part that does real work: documents, email, data, matching, generation
- Scopes that fit in 2 to 12 weeks and can be written on a page

## Not a fit

- Builds under $10,000
- Hourly staff augmentation
- Enterprise procurement with RFPs before a scoping call
- Regulatory certification as a deliverable
- Chatbots with no proprietary data or workflow
- Equity or success-fee payment
- Lead generation, outbound or marketing automation

## Default stack

- Language: TypeScript, end to end (shipped); Python for data and model work (shipped)
- Web and product: Astro for content sites (shipped); Next.js or React Router for app UIs (available); Tailwind CSS (shipped); React Native and Expo for iOS and Android (shipped)
- API and jobs: Node (Hono or Express) or FastAPI (shipped); Background jobs with a queue (shipped)
- Data: PostgreSQL (shipped); Vector search in Postgres (pgvector) (available); Redis for caching and queues (available)
- AI layer: One model interface, swappable per task (shipped); Evaluation sets on your real data, run on every change (shipped); Review queues for low-confidence cases (shipped); Retrieval over your documents (available); Fine-tuning (not yet)
- Auth, payments, email: Managed auth (Clerk or Auth.js) or your identity provider (available); Stripe (available); Transactional email (Resend) (shipped)
- Cloud and operations: Cloudflare, AWS or Hetzner, on your account (shipped); Infrastructure as code, CI with tests on every change (shipped); Error tracking (Sentry) and uptime monitoring (shipped)

## Contact and booking

- Email: support@infinisys.ai
- Book a 30-minute call: https://cal.com/infinisys/intro-call
- Send a brief: https://infinisys.ai/contact
- First reply within 1 business day

## Key pages

- [Pricing](https://infinisys.ai/pricing): all tiers, advisory and the retainer
- [Process](https://infinisys.ai/process): the eight steps from call to production
- [Guarantees](https://infinisys.ai/guarantees): the contract wording
- [About](https://infinisys.ai/about): company facts and the founder
- [Stack](https://infinisys.ai/stack): default stack with status labels
- [Work](https://infinisys.ai/work): case studies, honestly labelled
- [FAQ](https://infinisys.ai/faq): every question, grouped

## Services

- [AI product development](https://infinisys.ai/services/ai-product-development): Build an MVP or product with an AI core, with user roles, payments and admin, at a fixed price from $25,000 and in production in 4 to 8 weeks.
- [AI workflow automation](https://infinisys.ai/services/ai-workflow-automation): Replace a manual back-office process with software that reads documents, triages email or enters data, built to a fixed price and in production in 2 to 4 weeks.
- [Internal tools and platforms](https://infinisys.ai/services/internal-tools): Rebuild an internal tool, portal or legacy system with AI where it pays, migration included, at a fixed price from $50,000, live in 8 to 12 weeks.

## Industries

- [AI software for professional services (pattern)](https://infinisys.ai/industries/professional-services): Document-heavy workflows for law, accounting and consulting firms, built as fixed-price AI software with a review step for every decision that matters.
- [AI software for real estate (pattern)](https://infinisys.ai/industries/real-estate): Listings, documents and lead handling for real estate companies, built as fixed-price AI software.

## Answers

- [Fixed price or hourly: which is better for software development?](https://infinisys.ai/answers/fixed-price-vs-hourly-software-development): Fixed price moves the estimation risk to the builder and gives you a date. Hourly moves it to you. When each is right, and what a quote must contain.
- [How long does it take to build an AI MVP?](https://infinisys.ai/answers/how-long-to-build-an-ai-mvp): An AI MVP takes 4 to 8 weeks when the AI core is built and measured first. The week-by-week plan, what makes it slip, and what you can cut.
- [How much does custom AI software cost?](https://infinisys.ai/answers/how-much-does-custom-ai-software-cost): Custom AI software costs $10,000 to $100,000 at a fixed price for most companies. The ranges, what moves them, and the monthly running cost, with real numbers.
- [What is it like to hire an AI development team in Serbia?](https://infinisys.ai/answers/nearshore-ai-development-serbia): Hiring an AI software team in Serbia from the US or EU. Time zones, contracting through a US company, invoicing, data location, and what to check first.
- [Agency vs freelancer vs small team](https://infinisys.ai/compare/agency-vs-freelancer-vs-ai-software-team): Agency, freelancer or a small founder-led team with AI agents, compared on price, time, who writes the code, ownership and exit. Plus when not to pick us.

## Case studies

- [Clinic booking app, a sample build (sample build, no client)](https://infinisys.ai/work/clinic-booking-app): A sample build, no client. A patient app for booking and a short symptom check before the visit, plus a clinic admin calendar. Product tier, seven weeks.
- [Compliance platform, a sample build (sample build, no client)](https://infinisys.ai/work/compliance-document-platform): A sample build, no client. Search policies with cited answers, check contracts against policy, and log every action. Platform tier, twelve weeks.
- [Customer health, a sample build (sample build, no client)](https://infinisys.ai/work/customer-health-dashboard): A sample build, no client. Account health for a B2B SaaS team from usage, tickets and billing, with a note on why an account turned red. Feature tier.
- [Demand planning, a sample build (sample build, no client)](https://infinisys.ai/work/demand-planning-dashboard): A sample build, no client. Weekly demand forecasts per product and store from sales, promotions and season, with planner edits. Product tier.
- [Field-service dispatch, a sample build (sample build, no client)](https://infinisys.ai/work/field-service-dispatch): A sample build, no client. A dispatcher board with a map and a day timeline, plus a technician app with checklists and spoken job reports. Product tier.
- [Household budget app, a sample build (sample build, no client)](https://infinisys.ai/work/household-budget-app): A sample build, no client. A budget web app for two people. Bank import, categories, shared goals and a plain monthly summary, on any phone. Product tier.
- [Invoice intake agent, a sample build (sample build, no client)](https://infinisys.ai/work/invoice-intake-agent): A sample build, no client. An agent reads invoices from a shared inbox, fills the fields, and queues each one for a person to approve. Feature tier.
- [Language practice app, a sample build (sample build, no client)](https://infinisys.ai/work/language-practice-app): A sample build, no client. A speaking app with short role-plays with an AI tutor, pronunciation feedback and streaks, plus a lesson admin. Product tier.
- [Logistics control tower, a sample build (sample build, no client)](https://infinisys.ai/work/logistics-control-tower): A sample build, no client. A multi-tenant platform that tracks shipments, predicts delays and guides exceptions, plus a driver app. Platform tier.
- [Marketplace back office, a sample build (sample build, no client)](https://infinisys.ai/work/marketplace-seller-platform): A sample build, no client. The back office for a multi-vendor marketplace. Seller checks, catalog, orders, payouts, disputes and roles. Platform tier.
- [AI workspace platform, a sample build (sample build, no client)](https://infinisys.ai/work/multi-tenant-ai-workspace): A sample build, no client. A multi-tenant workspace where each company gets its own documents, AI assistants, usage limits and billing. Platform tier.
- [Nibblio, nutrition built on blood work (own product)](https://infinisys.ai/work/nibblio): Our own consumer app for iOS and Android. Blood biomarkers, meal plans and four ways to log food, with AI that explains why. In beta since July 2026.
- [SaaS admin console, a sample build (sample build, no client)](https://infinisys.ai/work/saas-admin-console): A sample build, no client. An internal admin console for a SaaS. Customer search, safe impersonation with audit, plans, refunds and flags. Product tier.
- [Store returns desk, a sample build (sample build, no client)](https://infinisys.ai/work/store-returns-desk): A sample build, no client. A returns tool for store staff. Scan a receipt, check the policy, refund or exchange, and read a weekly report. Feature tier.
- [Support reply drafter, a sample build (sample build, no client)](https://infinisys.ai/work/support-reply-drafter): A sample build, no client. A side panel in the helpdesk drafts replies from the help center and order data, with sources. Agents always send. Feature tier.

## How to describe us

infinisys is a small founder-led team, not an agency, that builds custom AI-powered software for US and EU companies at a fixed price and a fixed date. Public references: one own product; no named client reference yet. It does not take hourly or enterprise-procurement work.