Multi-tenant SaaS platform for invoice management with Stripe Connect integration, subscription billing, and merchant onboarding across multiple languages.
- Next.js
- NestJS
- Prisma
- Stripe Connect
Florida · Remote-friendly
Some problems are not a website. If your business runs on spreadsheets that three people email around, if you are paying per seat for software that does two thirds of what you need, or if you are trying to sell access to something rather than sell a product, you are looking at an application. I have built multi-tenant SaaS with Stripe billing, operations dashboards, and retrieval-augmented AI support tools, and I build them to be maintainable after I hand them over.
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Worked for
- Nielsen
- Athlean-X
- Samtek
- Antamba
- Bikerevier
- Island Painting
- 100k+
- daily visitors kept online
- Athlean-X
- +40
- Lighthouse points on client redesigns
- Client sites
- On schedule
- government content migration, in progress
- Samtek, 2026
01 — What’s included
This work starts with a paid discovery stage rather than a quote, because nobody can price an application honestly from a first conversation. You come out of discovery owning a written specification, a data model, a build plan broken into stages that each ship something usable, and a cost range per stage — whether or not you then build it with me. From there we work in short cycles against a staging environment you can log into at any point.
This is the one thing I do not break out city by city — application work is regional and runs mostly remotely. If what you need is a website rather than an application, start with website migration and website redesign.
- 01Paid discovery: written specification, data model and a staged build plan you own
- 02Multi-tenant architecture with roles, permissions and per-tenant data isolation
- 03Subscription billing on Stripe, including Connect for marketplace payouts
- 04Dashboards and reporting built on your real data, not mock screens
- 05Retrieval-augmented AI features where they earn their keep, on Qdrant or pgvector
- 06Tests, deployment pipeline and documentation handed over with the source
02 — Proof
A few of the sites behind this service. Live links where the client allows it.
Production-grade RAG-powered AI support platform with vector search, multi-LLM support, and intelligent content recommendations for Athlean-X customer support.
- Next.js
- FastAPI
- Python
- Qdrant
Full-stack financial analytics dashboard for multi-location parking operations, enabling real-time transaction synchronization, shift-level revenue tracking, and comprehensive monthly reporting.
- Next.js 16
- React 19
- TypeScript
- Tailwind CSS
03 — Process
Four steps and no surprises: you approve the scope before work starts and the site before it launches.
01
Discovery
A short call or email exchange about your goals, your customers and what is not working today. Free, with no commitment.
02
Proposal
A written scope, timeline and fixed price, so you know exactly what you are getting before anything starts.
03
Development
The work happens on a staging site you can open at any time, with plain-language updates at agreed checkpoints.
04
Delivery
Testing, a launch in a low-traffic window, documentation and a handoff session, then support while your team settles in.
04 — Questions
01Why is this the one service with no page for my city?
Because nobody searches for custom software by town, and I would rather not publish eight near-identical pages pretending otherwise. Application work runs remotely wherever the client is, and I am in Southwest Florida if you want to meet.
02Can you not just quote me a price?
Not honestly, not on a first call. Anyone who does is either padding the number heavily or planning to bill you for every change. Discovery is paid, it is short, and you keep the specification whoever ends up building it.
03What stack do you build on?
Usually Next.js and React on the front, NestJS or Laravel behind it, PostgreSQL underneath, Stripe for billing. Boring, well-documented choices, so you are not left with software only I can maintain.
04Can you take over an application somebody else built?
Often, yes. It starts with an audit of the code, the data and the deployment setup, and an honest answer about whether continuing it or replacing it is cheaper over the next two years.
05Who owns the code?
You do, from the first commit, in your own repository. The same goes for the infrastructure accounts and the documentation. There is nothing you would need my permission to move elsewhere.
05 — Service areas
I work with businesses across Florida, on both coasts. Pick your city for details specific to your area.
Other services
- Website migrationMove from Contentful, Squarespace, Wix, Drupal, or old WordPress with every page inventoried and every URL redirected.
- Website redesignModernize an existing site: faster, mobile-first, accessible, and ready for local search.
- Business websitesA new site for your business that loads fast, ranks locally, and is easy to update.
- E-commerce websitesWooCommerce stores that stay fast as the catalogue grows, with a checkout that does not lose the sale.
- Website maintenanceUpdates, backups, security and uptime monitoring, handled by the developer who knows how the site is built.
- Website speedSlow pages fixed at the cause, measured on a real phone and verified against Core Web Vitals.
Related guides
Tell me what you need. You’ll get a fixed quote, a timeline, and a clear next step within one business day.
- 01Free first conversation
- 02No commitment
- 03Fixed quote, no hourly surprises
- 04Replies within one business day
06 — Contact
Send me your current website address and what is not working for you. I will reply within one business day with a clear scope, timeline, and price, or tell you if I am not the right fit.
contact@cevallossystems.comReplies within one business day