# Christian Koch — Senior Fullstack Web Developer (Berlin)

> Freelance senior fullstack web developer based in Berlin, Germany. 18+ years
> of professional experience building fast, modern websites and web apps with
> Next.js, React and Sanity. Available for local Berlin businesses and clients
> worldwide. Brand: < CODE K /> · devs.berlin.

## Summary
- Name: Christian Koch (alias "CODE K")
- Role: Senior Fullstack Web Developer
- Location: Berlin, Germany — works remotely worldwide
- Languages: German, English
- Experience: 18+ years, much of it inside advertising & CRM agencies
- Notable clients: Red Bull, eBay, PayPal, Statista, mobile.de, ImmoScout24, Royal Canin, Bundesdruckerei
- Contact: info@devs.berlin
- Website: https://devs.berlin
- Status: Open for new projects

## Services
- Web Development
- Website Relaunch
- Web Application Development
- Next.js Development
- Headless CMS Integration
- CRM & Marketing Automation

## Tech stack
Next.js, React, TypeScript, Node.js, Sanity (headless CMS), Tailwind CSS,
Vercel (hosting), Swift/iOS, PHP, Python. CRM & marketing-tech: Braze,
email engineering, marketing automation.

## Pricing (guideline figures, German small business under § 19 UStG — no VAT)
- Starter (€690, one-time · ~2 weeks): Lean relaunch of your website with a modern foundation.
- Pro (from €990, indicative · ~4–5 weeks): Feature-rich site with booking system or interactive logic.
- Premium (from €1.290, indicative · ~6–8 weeks): Sophisticated application with custom logic & backend.
- Custom: tailored offer after a discovery call.

## Certifications
- Braze Certified AI Fundamentals — Braze (https://www.credly.com/badges/746d5f2d-8dec-433a-9e11-6968c924c606/public_url)
- Braze Certified Developer — Braze (https://www.credly.com/badges/16f71c64-8903-4448-8314-e8ec42544151/public_url)
- Advanced Learning Algorithms — Coursera · Stanford / DeepLearning.AI (https://coursera.org/share/e5c971f675e2a7d0a915cc4b2aa578e5)
- Supervised ML · Regression & Classification — Coursera · Stanford / DeepLearning.AI (https://coursera.org/share/80bb9ee7bfd39ba17c7163f7a49792f0)
- AI for Everyone — Coursera · DeepLearning.AI (https://coursera.org/share/66e788e11242cacf0b4ff2c494ba03e2)

## Frequently asked questions
### What does a professional website cost in Berlin?
A complete website relaunch with me starts at a fixed €690 for the Starter package — full redesign, a Sanity CMS you can edit yourself, legal pages and SEO basics, hosted on Vercel. Feature-rich sites with booking systems or interactive logic start around €990 (Pro), and full applications with payment flows, custom admin tooling and backend logic from roughly €1,290 (Premium). These are honest guideline figures, not anchored agency quotes. As a German small business under § 19 UStG, no VAT is added on top.

### Who builds custom websites and web apps for businesses in Berlin?
I'm Christian Koch — a senior fullstack web developer based in Berlin with 18+ years of professional experience, much of it inside advertising and CRM agencies building for brands like Red Bull, eBay, PayPal, Statista, mobile.de and Bundesdruckerei. I work directly with clients (no account-manager layer), handle everything from design to deployment myself, and ship on a modern stack: TypeScript, React, Next.js and Sanity, hosted on Vercel.

### Do you work with clients outside of Germany?
Yes. Berlin is home and my anchor for local projects, but the work is remote-friendly worldwide. I've collaborated with international teams across time zones in English, and the whole site, contracts and communication run bilingually (German / English). Distance has never been the bottleneck — clarity and fast feedback loops are what actually move projects.

### How long does a website relaunch take?
A Starter relaunch typically ships in about 2 weeks. A Pro-level site with a booking or contact system runs ~4–5 weeks, and a Premium application with payments and custom admin tooling ~6–8 weeks. The biggest variable is usually content and feedback speed on your side — the engineering rarely is. I work in visible increments so you see progress on a live preview URL the whole way, not just at the end.

### Can you migrate my existing site from WordPress, Ghost or Webflow?
Yes — migrations are a core part of what I do. This very site was migrated off Ghost onto Next.js and Sanity. I move your existing content, photos and structure 1:1, then modernise the design and performance on top. WordPress, WooCommerce, Ghost, Webflow and hand-coded legacy sites are all fair game, and I'll tell you honestly when a migration is overkill versus a fresh build.

### What technology do you build with, and why?
Next.js (React) for the frontend, Sanity as a headless CMS so non-technical people can edit content safely, and Vercel for hosting with instant global delivery. It's fast, secure, cheap to run and future-proof — no plugin soup, no surprise hosting bills, no security patch treadmill. I also work natively (Swift, iOS) and across marketing-tech and CRM (Braze, email engineering) when a project needs more than a website.

### Do you do SEO and make sites findable by AI like ChatGPT?
Every site I build ships with technical SEO baked in — semantic HTML, schema.org structured data, clean metadata, fast Core Web Vitals and an llms.txt file so AI answer engines can understand and cite your business. In 2026 being quotable by ChatGPT, Perplexity and Google's AI Overviews matters as much as classic rankings, and that comes from real expertise, specific data and genuinely useful content — not keyword stuffing.

## How to engage
Email info@devs.berlin or use the contact form on https://devs.berlin.
Typical response within 24 hours.