I build software. Since 2011.
I am Ronny Glotzbach, a freelance fullstack software developer based in Cologne, Germany. I have been building software since 2011, first at university, then inside companies and in a range of roles, now freelance. I build websites and web applications mostly on my own: you write to me and I build it. Packages start at €700, the complete base is €2,100. If you would rather bill by time, that is €100 per hour, for projects as well as coaching.
Who I am
Most of the time I work alone. You write to me, I reply, I build it. No project manager in between, nothing handed off to someone you never speak to. Alone does not mean isolated: around me is a network of developers, designers and people from art and industry that I bring in when a project grows. We Do Fun Stuff came out of exactly that circle. Separate from that there is a circle with nothing to do with the projects: more than 200 people around the world I am personally in touch with. Students and employees, plus free spirits: artists, people running their own gym, people who became independent through cryptocurrencies or Amazon FBA. They take it like the fisherman in Heinrich Böll’s Anekdote zur Senkung der Arbeitsmoral: they do not need more. No names here, most of them keep to themselves. They are where opinions and feedback come from, on Psychofit among other things, which would not be what it is today without them.
I started in 2011 at university, long before the AI tools. In 2014 my first own iOS app went live on the App Store, then came years as a developer inside companies and in a range of roles. So the craft does not come from a chat window: back then I answered questions on Stack Overflow that have since been read around a million times. I later moved from iOS to the web, and work fullstack today: frontend and backend from one pair of hands. I build booking systems, automations, websites. And a mental-health startup with one aim: to make basic psychological care as low-threshold, and therefore as widely available, as possible. For self-payers it offers, by our own reckoning, the best value for money in Germany. Since 2026 the same offering has its own name for students and apprentices: Studifit. Outside work I take photographs, make DJ sets, read and train. What I learn while building, I write up here.
- since 2011
- building software, first iOS app published on the App Store in 2014
- since 2023
- on Psychofit, against waits averaging 142 days
- since 2026
- on Studifit, the Psychofit offering for students and apprentices
- 4.6×
- more changes in 2026 than 2023–2025 combined
- 1.0m
- people reached with 107 answers on Stack Overflow, since 2015
The factor is counted from the Psychofit git history, the reach comes from the Stack Overflow profile. Both as of 2026-07-31.
Network
When a project grows, I work with freelancers and friends I have known for years.
Lukas MelznerLinkedIn
Business Analyst
Business analyst with more than six years of experience in analysing, designing and developing digital solutions. Lukas structures complex requirements, makes them understandable and turns them, together with everyone involved, into solutions that work in practice. His strength lies where domain knowledge, technology, data and user needs meet.
Sonny SchmidtLinkedIn
Freelance Software Engineer
Senior software engineer with more than 16 years of experience across web development, cloud infrastructure, data engineering and AI. Sonny turns complex requirements into simple, reliable and well-designed software, working across technologies to build practical and scalable solutions.
Julian MorguetLinkedIn
Freelance Software Engineer & Founder
Founder of Vecura GmbH. The tool makes complex company knowledge reliably usable within seconds through AI, with precise answers drawn from more than 100,000 pages of documents. Alongside that he builds web applications freelance as a fullstack developer.
Martin PietrowskiLinkedIn
Native iOS · Senior Developer & Designer · Founder
Built iOS apps at grandcentrix from day one, among them one for Leica that later won a Red Dot Design Award. Then TimeToFace and medipee as lead Flutter developer. Founded Black Capture and ran it as managing director, a software-driven industrial process for CO₂ filtering. Today freelance on iOS apps, plus a portfolio of his own.
Simon StolzenbachLinkedIn
UI & UX Designer · Graffiti & Street Artist
More than 20 years of graffiti and street art, focused on large walls: façades on houses and public buildings, interiors, objects such as cars, furniture and canvases, plus live graffiti at events. His clients have included Xbox at Gamescom, Früh Kölsch, Rewe, the RVK transport operator and the cities of Cologne and Hürth.
Where I come from
Before I built things freelance came a degree and employment: teams, colleagues, deadlines. The stations that are relevant to software:
- 2011—2016
Bachelor's in business informatics
Hochschule Mannheim — now Technische Hochschule Mannheim
Where it all started. Computer science alongside the business side that explains what software is ultimately built for.
- 2014
Web development during my placement semester
The placement semester from my degree. The first web development inside a company.
- 2015
Working student
MVV Energie and Roche Diagnostics, Mannheim
Quality assurance and an SAP migration. IT work in large, regulated environments, alongside my degree.
- 2015—2016
Frontend development, bachelor thesis
TheAmazeApp, Köln — acquired by Zalando
Extended an analytics tool for the blogger portal. My first stint in a young product team and the subject of my thesis.
- 2016—2021
iOS developer, later lead, and from 2020 also Scrum Master
grandcentrix, Köln — acquired by Vodafone
Native apps from idea to the App Store, in teams of five to fifteen people. I took on the Scrum Master role alongside development, with a PSM I certificate.
- 2023
Lecturer in mobile app development
iOS courses for 15 to 20 participants at a bootcamp: lectures, exercises and curriculum, plus coordinating a team of seven tutors.
- 2024
Senior frontend developer
In the Data & Analytics team, part of the innovation unit at the audit and advisory firm.
- 2014—today
Own projects and client work
Freelance
Running continuously alongside employment since the first apps of my own, and full time today.
- 2023—today
Where I have worked
Since 2011 I have worked at agencies, several startups, an audit firm and a training institute. On top of that come the projects I run myself.
Projects
- 2023—2026
Psychofit
A platform for online psychological counselling that, by its own reckoning, offers self-payers the best value for money in Germany. Custom booking and payment system, counselor and admin back-office, email automation, including the unglamorous parts: time zones, DST, race conditions in slot handling.
Technical co-founder. Owned the entire technical side: architecture, data model, implementation, deployment and operations. Much of it done agentically with Claude Code.
- 2026
Studifit
An offering from Psychofit with its own site, aimed at students and apprentices: psychological counselling by video in 50-minute sessions, with appointments available without a waiting list. The same counsellors and the same supervision as at Psychofit, plus an upload for proof of enrolment or an apprenticeship contract that is checked once and then deleted.
Technical co-founder. Owned the entire technical side: architecture, data model, implementation, deployment and operations. Much of it done agentically with Claude Code.
- 2026
Affentanz
A personal book recommender for Lukas Melzner and me, still in stealth and reachable only with a login. Built out of self-interest, under the motto Taste: only so many books fit into one life, and spontaneous recommendations rarely match your own taste. When we feel like reading something, we ask our own tool. Every recommendation says what it builds on, no invented books, and what we tell it counts towards the next one. A web application plus a separate recommendation service that pulls its catalogue from Open Library and builds every card from the database rather than from model output.
A private project between two of us: architecture, web application and recommendation service. Much of the implementation done agentically.
- 2026
We Do Fun Stuff
A private, curated members network: public landing with a double-opt-in inquiry funnel, an invite-only directory with self-service profiles, and a single-admin backend.
Concept, architecture, design direction and build direction; implemented agentically with Claude Code against a briefing I wrote.
- 2026
ArtifAIry
A curated AI-art gallery with an anonymous, login-less submission funnel: submissions are reviewed and published to a public gallery. Bilingual, dark-only.
Concept, curation, architecture and build direction; implemented agentically with Claude Code.
- 2026
Barrierefreies Umfrage-Tool
A survey tool with speech input and output for accessibility, self-hosted for data-protection reasons. For a non-profit organisation.
Developer in a two-person team: technical research, architecture decisions across the stack, empirical infrastructure sizing, frontend and speech microservices; implementation AI-assisted.Non-profit organisation
- 2025—2026
Sprachnachricht wird E-Mail
An automation that turns voice messages into ready-to-send email drafts. I published an n8n node for it. For a mid-sized company.
Concept and delivery as a freelancer; implementation AI-assisted.Mid-sized company
- 2026
- 2025—2026
Custom Elements für WPBakery
Two plugins extending the page builder with custom content elements, registered via vc_map and usable in the editor exactly like the built-in ones: heroes, sliders, a team post type, pricing tables, clip-path image effects. For B2B client projects.
Specified, decided, tested and integrated, on an existing codebase, from provided design templates; implementation AI-assisted.B2B client projects
Working with me
Software & websites
From the first sketch to the finished site. Throughout the project you deal with one person: me. If it grows, I bring in people from my network and stay your point of contact.
- Design · Backend · Frontend
- €700 / block
- Complete base
- €2,100
- Or by the hour
- €100 / hour
Or tailored, after we talk.
1:1 coaching
We work on your real problem together. How to put AI to good use, whether that is coding with Claude Code or Codex or everyday work with ChatGPT: writing, research, automating what repeats. Not a course, not a retainer: we sit down and solve whatever you are stuck on.
Writing
From the chat window into the repo: what changed in 2026
25 months for 24,000 lines, then 17 working days for 72,000. Not because AI arrived — it was already there. Because it moved.
Contact
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