Manual order processing costs 15–30 min per order. Here's the full automation pipeline I built: Stripe → CRM → shipping → invoice → email in 2 minutes.
Blog
Deep dives on Python, React, TypeScript, system design, and lessons from real-world freelance projects.
EU VAT validation in Next.js breaks in ways tutorials don't cover. VIES caching, silent failures, reverse charge logic — here's what actually works.
Every production SaaS needs the same foundation. Here's the 40+ point checklist I use: auth, billing, database, API, email, monitoring, security — with
Stripe retries webhooks for 72 hours. Naive handlers duplicate orders. Here's the production architecture: idempotency, BullMQ queues, signature verification.
SSR, meta tags, JSON-LD schemas, Open Graph — the technical foundation that makes sites indexable. Not a service, just proper engineering.
A PDF contract arrives. How do you know if it's been edited? Here's the xref table trick and 7 forensic markers I built into htpbe.tech to detect PDF tampering.
Next.js i18n with App Router at production scale — routing, type-safe translations, hreflang, and the formatting traps no tutorial warns you about.
How I built a RAG chatbot that resolves 70% of support queries across 25 languages — ingestion pipeline, hybrid search, confidence thresholds, and streaming UI.
How to implement sliding window rate limiting in a production API — Redis ZADD pattern, in-memory fallback, multi-tier limits by IP and API key, and the
12 years as CTO, then independent. What changed, what surprised me, and what I learned about senior developer freelance work in the EU market.
Client-side analytics is broken by iOS privacy and adblockers. Here's how I implemented 100% server-side GA4 Measurement Protocol + Meta Conversions API in
I've used both in production — Puppeteer for Pikkuna's Finnish VAT invoices, @react-pdf/renderer for pi-pi.ee's Cyrillic invoices.
One repo, one TypeScript config, shared types between frontend and backend.
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I take on freelance projects for EU startups and SaaS founders. Let's talk about your idea.