One engineer, hired directly. I build the software specialist businesses run on. Fixed prices, weekly demos, and code you can keep.
Everything below has a fixed scope and a fixed price, agreed before I write a line of code. Not sure which fits? The call is free and we can arrange something.
Something new, delivered working.
A single, hand-built page for a new business or a side project: who you are, what you do, and how to get in touch. Your content, a contact form, and fast on any phone.
Fast, hand-built marketing sites like this one, with several pages and a design made for you. Designed and live in two weeks, with a simple way for you to edit the text yourself.
Bespoke systems for specialist businesses whose work doesn't fit off-the-shelf tools: marine consultancies, surveyors, inspection and technical services. A one-week discovery first, on site or over video calls, then built in fixed-price phases. Projects typically run €15,000 to €40,000.
A working first version of your product in four weeks. Scope agreed up front, one price, weekly demos, and a real deployment at the end.
Practical AI built into the work you already do: an assistant that answers from your own documents, automatic sorting and summarising of incoming email or tickets, or drafting routine paperwork from your own records. Two weeks to a working pilot, on your data, with clear limits on what it's allowed to do.
Connect the tools you already use. Replace the copy-paste-into-a-spreadsheet step with code that runs itself and tells you when it didn't.
Senior judgment without a senior hire.
A second opinion before you commit: choosing vendors, reviewing a proposal or an estimate, due diligence on a codebase you're buying, planning a roadmap. Available by the day, or as a standing few hours a month for founders without a technical co-founder.
One week inside your codebase, then a written report: what's risky, what's quick to fix, and what to leave alone.
Architecture overviews, API references and onboarding guides, written from your actual system rather than what it was meant to be. For teams that need to hand over, hire, or get an audit through. Requirements documents are a different job: workshops with your stakeholders, several review rounds, and a document that everyone signs. Priced accordingly.
A senior engineer inside your team, for a while.
Available for contract work: cover a gap, lead a migration, or ship the thing nobody on the team has time for. Your repo, your process, your stand-ups. Remote from Amsterdam, on site in the Netherlands by arrangement.
Keep what you have working.
Send me a URL or a website in development. Within 48 hours you get a written report: speed, accessibility, SEO, security headers and hosting cost, with the fixes in priority order and what each one is worth doing. Book and pay, no call needed.
Hosting, updates, backups, uptime monitoring and small changes for sites and apps I've built or inherited. You email, it gets done.
Prices exclude VAT. "From" prices and timings are for the smallest version of each service. Anything bigger is scoped in a paid discovery week and quoted in fixed-price phases, so the number you agree to is the number you pay. Urgent starts and on-site days are quoted separately.
For the past two years I've been an engineer on a small development team for an international marine consultancy: surveyors, engineers and scientists handling casualties, claims and inspections around the clock, worldwide. I built and run the platform the whole firm works in, from the case record to the invoice, and a separate vessel-tracking and satellite-imagery tool for the analysts. It's the industry I know from the inside, and most of it still runs on Word templates and email. I also run my own AIS and ADS-B receivers at home and write about what they pick up in Wingmast.
Operations platform, international marine consultancy
50+ consultants and surveyors across multiple offices around the globe, one system for every job: case and claims records with vessels, parties and staff; a document store that mirrors the firm's own file server, with versioning and correspondence filed against the case; timesheets and expense claims that flow straight into invoices; nightly sanctions screening; and an AI assistant, inside Outlook, that briefs each user from their own mailbox and drafts replies they send themselves.
Every receipt is read and checked automatically: OCR, image forensics, duplicate detection and a reasoned flag for finance to review.
Vessel tracking and satellite analysis tool
Voyage reconstruction from AIS and satellite trackers on an interactive map; satellite imagery tiled on demand over an incident position; oil-slick search from open detection data; vessel motion analysis from onboard sensor uploads. Results shareable with clients by a single link, no login.
Marine surveyors and consultancies, P&I correspondents, salvage and offshore inspection firms. Also loss adjusters, forensic engineers, asset and building inspectors: any expert business whose work is a stream of jobs, evidence and reports.
The same four steps for every project, so you always know what happens next.
Thirty minutes on what you need and what you've tried. No pitch deck.
Within two working days: scope, price, and a start date, in one page.
You see a working version every week and can steer as we go.
Code in your own repository, documentation written for the next engineer, and an optional care plan. Nothing depends on me staying.
Web front ends are the visible part. Most of the work is underneath: data pipelines, geospatial processing, document generation, AI checks, and integrations between systems that were never designed to talk to each other.
Job queues, schedulers and workers for long-running tasks; multi-gigabyte file transfers to on-premise storage; row-level locking and audit trails for money and evidence. Python, Django, FastAPI, PostgreSQL, Redis
Satellite imagery tiled on demand from open archives; AIS and satellite-IoT tracker feeds on live maps; frequency analysis of onboard motion sensors. GDAL, rasterio, NumPy, SciPy, Mapbox GL
LLM pipelines with token budgets, human sign-off and a log of every call; receipt OCR and tamper detection; fuzzy matching against sanctions lists. Claude API, Pillow, perceptual hashing
Word and PDF generation from templates; .docx editing in the browser; add-ins that live inside Outlook and Word; server-side mailbox integration. python-docx, Office.js, Microsoft Graph
Internal web apps used daily by 50+ people; real-time updates over WebSockets; browser extensions; public share links that need no login. React, TypeScript, Chrome MV3, Django Channels
Containers, CI, staged deploys, two-factor auth, API keys with rate limits, monitoring. Test suites that run against real storage and a real database, not mocks. Docker, GitHub Actions, pytest, Playwright, Cloudflare

Petricore Labs is currently just a sole engineer, not an agency. I've spent the last few years as a developer for a single company, owning everything from the database to the deploy button. That's the experience I bring to your project: someone who you can hold accountable for decisions.
I'm now taking on a small number of additional clients. Small enough that you'll always talk to the person writing the code.
The name comes from petrichor, the smell of rain on dry ground. No deeper meaning. I liked the word.
Tell me what you're trying to get done. I'll reply within one working day.
hello@petricorelabs.comOr pick a time directly: cal.com/petricorelabs/intro