Production MVP in 4 to 6 weeks, live with real users. Streaming LLM features, payments, admin, deploy. You own every line of code.
Case study
IBICASA is a live multi-tenant property marketplace for Ibiza. One Rails codebase serves the public portal, the admin panel, a partners REST API and a company portal, routed by hostname.
A free tool for founders: paste your website, answer up to three questions and get the AI feature most likely to make your business money, sized and with a rough timeline. Built in Next.js and TypeScript with streaming Claude replies, on Vercel.
Ticketing platform for an international jazz festival at The Standard, Ibiza. Per-concert tickets with cart and checkout, instant e-tickets scanned at the door, a box-office cash register, hotel room booking and invoicing. Rails and Hotwire, live for the 2026 edition.
Production client site shipped in 2018 and still running: enquiry flows with Slack webhooks and automated email, built for a villa rental business.
Services
Multi-tenant apps, auth, payments, admin panels. For new products I default to Rails and Hotwire: boring, fast, maintainable, the stack behind Shopify, GitHub and IBICASA.
Claude and OpenAI integration, streaming UIs, tool use, structured outputs and background pipelines. Prompts and evals your team can maintain after I leave.
Six years in audit at PwC, Crowe Horwath, Cox & Partners, PKF Wallast and Flynth. Audit trails, controls and precision are native to how I build, not learned on your project.
Process
30 minutes, free. I ask the awkward questions, then we decide whether it's worth building at all.
A scoped, priced proposal within 48 hours. Fixed price, fixed timeline.
Weekly shipped demos on a staging URL. You see progress, not status reports.
Your repo, documentation, tests and deployment. No lock-in.
Pricing
from €9,900
A production Rails app in 4 to 6 weeks. You own the code.
from €4,500
Two weeks adding one AI-powered flow to your existing app.
€3,900 / month
Senior product and AI work, 2 days a week. Cancel monthly.
Add-on, once your tool is live
Keep the tool patched, monitored and improving after handover.
| Included | Care (after a Sprint) | Care+ (after a Build) |
|---|---|---|
| Price | €350/month | €550/month |
| Hosting | Hosting runs in your own account (Scalingo or your own cloud), billed to you directly by the provider. I set it up and manage it for you. | |
| AI usage | AI usage passed on at cost, shown on the invoice. | |
| Maintenance | Security patches, Rails and gem updates, uptime monitoring, monthly backup restore test. | |
| Small changes | 2 hours/month | 4 hours/month |
| Response | Next working day | Same day for anything that blocks your users |
| Extra | Annual export of the AI log | Quarterly call: what to improve next |
| Term | 3 months minimum, then cancel monthly. | |
Planning a new build? Not ready to commit?
A paid half-day working session before you commit to a build. You leave with a written scope, a fixed quote, and an honest go/no-go recommendation.
The full €750 is credited against an MVP Build or AI Feature Sprint booked within 30 days.
Prices exclude VAT. Larger scope quoted after the call.
Start smaller
€750
For founders and SaaS teams with an existing codebase: a technical review of your repo against EU GDPR and AI Act, plus national rules. A technical review, not legal advice.
What usually comes next: a fix Sprint, or ISAE 3402 readiness.
Ask about a scan€4,500
For SaaS teams selling to finance. We prepare you. An independent audit firm performs the audit and issues the report. Bought the GDPR + AI Act scan? €500 of it is credited, as much of the work overlaps (access, logging, subprocessors).
What usually comes next: a Sprint to close the gaps.
Ask about readinessPrices exclude VAT.
FAQ
That's what the first call is for. If an off-the-shelf tool, a spreadsheet or no build at all is the better answer, I'll tell you. Saying no early is cheaper for both of us.
No account managers, no handoffs, no junior you never met. If your project genuinely needs a team, I'll say so on the first call.
No. You get the running product and a plain-English map of how it works, so you're not renting understanding of your own system.
Fixed prices, quoted before anything starts. Packages are listed above; larger scope is quoted after the call.
Yes, two ways. A Scoping Session (€750) plans a new build: you leave with a written scope, a fixed quote and a go/no-go, and the full €750 is credited against an MVP Build or AI Feature Sprint booked within 30 days. A GDPR + AI Act readiness scan (€750) reviews code you already have and ends with a prioritised fix list.
Two weeks for an AI Feature Sprint, 4 to 6 weeks for an MVP. The variable is usually how much of your process lives only in someone's head.
Weekly demos on a staging URL mean you see problems in week one, not week six.
Yes. Your repo, docs, tests and deployment from day one. No lock-in.
About
Six years in audit at PwC, Crowe Horwath, Cox & Partners, PKF Wallast and Flynth. Then eight years shipping production Rails. Dutch and US citizen, based in Spain, working remotely with teams across Europe and the US.
I run IBICASA.com as sole engineer and build with AI-assisted tooling every day. Le Wagon AI Software Development bootcamp, 2025. Masters in Accountancy and Controlling, Groningen.
Rails is home. When your product lives in React, Python or a codebase someone else started, I work in it the same way: AI-assisted tooling, tests before changes, small reviewed pull requests. Mosswerk Ideas is the latest example, built in Next.js and TypeScript. You'll know up front where I'm on home turf and where I'm not.
Working with one person means no handoffs, no account managers and no junior you never met. You get senior judgement from the first call to the last deploy.
Send a short brief and you'll get a scoped, priced proposal within 48 hours. Or skip the form and grab a slot.
Book a 30 min call