Hello.

My name is Tim. I've built software for 28 years - these days mostly with AI. Employed at comspace in Bielefeld, day-to-day work: DXP* projects. Based in Rietberg in East Westphalia, preferring remote - the way I have worked since 2020.

* Digital Experience Platform - the combination of content management, commerce, customer data and analytics through which a company reaches its customers consistently across every channel.

My career What I build

Scroll down

About me

Generating code got easy. Owning it did not.

In 1998, in my first year of training as an IT specialist for application development, they drilled one thing into us: in this profession, the learning never stops. That's exactly how it played out - and exactly why I still love this job. I bet on internet technologies early, because that's where I saw the most exciting and most consequential field.

In my early twenties the path seemed clear: vocational training, a start at Siemens, a media informatics degree alongside the job. At 25, a serious illness arrived instead. I got through it - and afterwards I deliberately let go of the degree. Not out of weakness, but out of clarity: from then on, practice was my school, and it has never let me down. What remained is an attitude that carries me to this day: I know how to endure. And how to set priorities.

Since then I've watched every major shift from the front row: static HTML turning into interactive applications. Steve Jobs in 2007 projecting a keyboard onto a sheet of glass, swiping it away, tilting the iPhone, playing a video in 16:9 - and the web going mobile. And in November 2022, ChatGPT arrived. I knew immediately: this changes software development fundamentally - and my own work along with it.

ChatGPT called my professional DNA into question. But giving up isn't in me - that was true once before in my life, and it was true again now. Instead of fear or resignation, I set out to truly master this technology. The genie is simply out of the bottle and it is not going back in. That is where my two focus areas came from: AI knowledge management and AI-assisted development. Structuring context so models answer reliably instead of randomly - and keeping ownership of what comes out of it.

The same endurance drives me beyond the code: my Hermannslauf debut at 47, my first marathon at 48. And passing things on is part of it: since 2007 I have moderated the Runners World running forum, and at Druffeler SG I am club secretary, coach the youngest (Bambini) footballers and look after the club website I built myself. Personal: husband and father of two grown children.

What I do

AI knowledge management, automation, websites.

I make existing knowledge usable for AI - so it looks things up instead of guessing.

A model without your knowledge is a bright intern on day one - it guesses politely. I build the layer underneath: AI knowledge management means bringing notes, project knowledge and decisions together so the AI looks things up in them while it works - and so new knowledge grows into them as the work goes on. My own knowledge base has been running since early 2026 and carries the context of more than a thousand documents.

I automate workflows with AI agents - held in a harness, not left to themselves.

Agents that work on their own need guardrails - otherwise they will eventually do something nobody wanted. That is exactly what a harness is: the frame that defines what may run unattended, what gets submitted for approval and what is blocked, plus a log that cannot be altered after the fact. For the steps that repeat every day I built myself more than 25 custom tools rather than doing the same task ten times by hand. They live in private repositories - I am glad to show examples on request.

I still love building websites - AI is getting very good at this, but it doesn't have the eye you earn in five years at a design agency.

Five years at a design agency are still in there, and they do not wear off. AI writes usable website code today - what it cannot do is decide what to leave out. My websites run without third-party services and without a maintenance contract that only produces invoices - a WordPress site I had built myself years earlier is exactly what I replaced for that reason. The side business has existed since 2018: a handful of websites for freelancers and clubs in the region, outside working hours and on a small scale.

View projects

Career

28 years of experience, one constant: building solutions.

From my start in software development through the design agency to the AI engineering of today.

Résumé (PDF)

Profile at a glance

Core today: Vue.js · Nuxt · TypeScript · headless CMS (Storyblok) · Astro
AI work: Claude Code · AI agents in a harness · AI knowledge base · test-driven with AI
Foundation: .NET (C#) · T-SQL · TYPO3 · PHP · Sitecore (Certified Platform Associate)
Always on: Performance · technical SEO · accessibility · GDPR

since 08/2024

Senior Software Developer · comspace

Back at my professional home: DXP solutions with Vue.js, Nuxt and headless CMS.

Return to comspace GmbH & Co. KG in Bielefeld after a stint in test-driven product development - a digital agency specialising in digital experience platforms: content management, commerce, customer data and analytics grow into one platform there, through which a company reaches its customers consistently across every channel. Frontend development with Vue.js, Nuxt and headless CMS (Storyblok) for mid-size to complex web projects, component work in Storybook.

Vue.js
Nuxt
Storyblok
Storybook

05/2024 - 07/2024

Frontend Engineer · WPS Management

A short step into product development - a SaaS purchasing platform.

A deliberate step into product development: WPS builds a SaaS product, a web-based purchasing platform - for me the loop back to my Siemens days with the e-procurement solution eBanf. Technically: user interfaces with TypeScript, Vue.js and Cypress E2E, in an English-speaking environment. Secured with an option to return to comspace - and when the move did not meet my expectations, I went back after three months.

TypeScript
Cypress
SaaS

since 2018

Websites & AI engineering · side business

Websites for small clients - since 2023 AI engineering.

My side business has existed since 2018 - through it I build websites for small businesses and freelancers. Since early 2023, AI has been my daily tool: first as a code companion in reviews, then in generation - always with the ambition to probe its limits instead of guessing. In 2023-2024 a few smaller website projects of my own came out of that; since 2024 I work test-driven with AI: I define what gets tested and why, the tests are generated, and my own test agents verify the results - separate from the tool that produced the code. Since 2025, agent-driven planning on top, plus a harness of my own with more than 25 skills.

AI Engineering
Knowledge Management

12/2017 - 04/2024

Senior Web Developer · comspace

Six and a half years of digital experience platforms with Vue.js, Nuxt and headless CMS.

comspace is my professional home: from late 2017 I built complex web projects here - from idea to launch, with an eye on performance and technical SEO. Until 2020 I built .NET web applications with Sitecore (Sitecore Certified Platform Associate). comspace specialises in Digital Experience Platforms (DXP): I worked with Vue.js and Nuxt plus headless CMS like Storyblok and integrated full customer infrastructure and API services.

DXP
Vue.js
Nuxt
Headless CMS

08/2017 - 11/2017

Application Developer · heroal

A deliberate step from agency life into industry - and quick clarity about where I belong.

After the agency years, a deliberate move into industry: application development at building-systems manufacturer heroal. I resigned during the probation period - it quickly became clear that I missed agency life with its variety of projects and clients. Returning to the agency world at comspace was the consequence.

Anwendungsentwicklung
Inhouse

10/2015 - 07/2017

Senior Web Developer · TERRITORY CTR

Responsive TYPO3 websites, technical point of contact for censhare.

I joined to help build an in-house development team. I built database-driven, responsive websites with TYPO3, PHP and SCSS and was the technical point of contact for the enterprise CMS censhare - focused on XSLT, interfaces and customizing. When the agency moved from arvato to Gruner + Jahr, the decision was made to hand development back to external partners - the reason I had joined was gone.

TYPO3
PHP
censhare

12/2010 - 09/2015

Web Developer / Team lead · A3PLUS

Technical project and team lead at the design agency.

After twelve years in a corporation, a deliberate move to the design agency: away from intranet web applications, towards visible design and client projects with short paths. Five years in a design agency - where I developed my trained eye for the visual. I held the technical project and team lead for e-business and built web projects with TYPO3 and PHP to UX/UI specs.

TYPO3
Teamleitung
Frontend

since 2007

Moderator · Runners World Forum

Forum moderation - grew out of laufen-aktuell.de.

After I sold laufen-aktuell.de, Runners World took over the forum - I have kept moderating it ever since.

Community
Moderation

2001 - 2007

Founder & Operator · laufen-aktuell.de

My running community: built it, ran it for six years, sold it in 2007.

My running community: built alongside my early Siemens years, ran it for six years and sold it in 2007 - the forum lives on at Runners World.

Community
PHP

1998 - 2010

Software Engineer / IC Consultant · Siemens group

Twelve years in the Siemens group - from vocational training through my working-student years to the SAP-integrated e-procurement solution.

My start in software development: vocational training as an IT specialist at Siemens AG (1998-2001), then working student at Siemens Business Services alongside my studies (2001-2004). Netzwerk Service GmbH, a company within the Siemens group (2004-2006), was my way back into the corporation and into permanent employment: from 2006 Siemens IT Solutions and Services. My focus: .NET (C#/VB.NET), T-SQL and web services. It started in 2004 with migrating an Access-based creditor search to the web - the proof of concept for the electronic purchase requisition "eBanf": step by step I turned Access and paper forms into an intranet procurement portal, first for one organisation, then the system grew to cover cost centres, number ranges and account assignment types for more. Integrated with several SAP systems, I technically led and evolved it over five years.

.NET
C#
SQL

Selected work

What I've built lately.

A selection - from AI-assisted tooling to a volunteer-run club website.

AI tooling

2 projects AI in the workflow

Knowledge base 2026

AI knowledge base

Notes, project knowledge and decisions, searchable via embeddings, with context tooling for Claude Code. Knowledge that outlives a single session instead of vanishing with it.

Knowledge Management
RAG
Embeddings
Claude Code

Also in: Applications

Custom tooling 2026

Custom tooling for Claude Code

25+

custom skills

15+

custom commands

Custom skills and commands for the steps that keep repeating - identical on every machine, via symlinks and Git. Rather than doing a task ten times, I build the tool for it once.

AI Tooling
Automation
DevEx

Also in: Applications

Select a project to see the details.

Applications

1 project Custom applications

Booking plan 2026

Druffeler SG - booking plan with self-service reservations

Ten pitches and rooms at Druffeler SG, previously tracked in separate manual calendars, now run on one shared booking plan with self-service reservations and self-managed cancellations: whoever books a slot can cancel it again themselves - managed directly through the website, with Google Calendar as the data store and a server-side layer so no access key ever reaches the browser. A year-long series is checked in six seconds, a single slot in under a hundred milliseconds, and the plan looks a full year ahead.

Nuxt
Apps Script
Performance
Volunteer

Also in: Care and maintenance

View project

Select a project to see the details.

Websites

3 projects Building and shipping websites

Lebensreisen 2026

Lebensreisen - website for a funeral speaker

Concept, design and build for an independent funeral speaker - a lean site with no ongoing add-on services, cheap to run and needing almost no upkeep. In a field where calm and privacy matter more than effects.

Static-Site
GDPR
SEO
Design

View project

Schönes von Tina 2026

Schönes von Tina - handmade goods label

One-pager for a handmade goods label with a self-service cabinet by the front door. Sales run through Instagram; the site is the dependable address behind it.

Static-Site
Accessibility
GDPR

View project

Pizzeria Due 2025

Pizzeria Due - website under new management

Menu as a PDF with image previews, ordering by phone and WhatsApp instead of a system nobody would maintain day to day. The simplest solution that actually gets used.

Static-Site
Local Business
Performance

Also in: Care and maintenance

View project

Select a project to see the details.

Care and maintenance

2 projects Replacing and maintaining existing systems

Hof Abing 2026

Hof Abing - out of the maintenance trap

A WordPress site I had built myself years earlier had turned into a maintenance burden: updates, plugins, database backups - upkeep nobody has time for. Instead of lifting it to the next WordPress version, I changed category: a static site, no CMS, nothing left to rot. It is maintained by voice - the family dictates a change, the AI applies it, and the upload to the webspace follows automatically.

Static-Site
Voice-to-CMS
Auto-Deploy
GDPR

Also in: AI tooling · Websites

View project

Druffeler SG 2025

Druffeler SG - club website

A youth football club's website, built and continuously maintained - as a volunteer, alongside my role as club secretary and Bambini coach.

Nuxt
Vue
Volunteer
Maintenance

Also in: Websites

View project

Select a project to see the details.

Questions

What people want to know first.

Eight questions that usually come up before a first conversation.

Are you looking for something new?

Not actively. I am in a permanent role and I like where I am. At the same time, AI is putting a lot to the test right now - roles, workflows, entire business models. I keep my own work flexible, and that goes for my environment too: it gets interesting when AI is part of the craft in a role rather than an add-on - then I am glad to talk. And if it does not fit, I will say so early instead of keeping you waiting.

What kind of role is worth approaching you about?

The kind where both are needed: someone who builds, and someone who takes a team along into working with AI. That does not require managing people - technical leadership is enough: setting standards, doing reviews, showing rather than prescribing. I have been doing exactly that since 2007 as a moderator of the largest German running forum, where I am named in the imprint - moderating there means what it means in a team: setting rules people follow because they make sense, not because they were ordered. What qualifies me technically is not the tooling but 28 years of practice: if you want to explain to sceptical developers why their work is changing, you have to know first-hand how it feels.

Imprint at runnersworld.de

In German or in English?

German is my working language. English: Cambridge First Certificate (grade B, 2000) - I read documentation and code fluently and can hold my own in conversation, but I would not call it negotiation-level. I am most at home in a German-speaking environment.

How do you work with AI?

I define how something is built, where the boundaries between the parts run and what the result has to do - much of the implementation is then generated. It still gets read and checked line by line: if you cannot judge what is being produced, you will not notice when it is wrong. Having code generated is something anyone can do now. Owning it is the work.

We are just starting out with AI - what would you do first?

Not start with the tool - start with the knowledge. A model knows the world but not your everyday work - and your most valuable knowledge is exactly what is written down nowhere: why a decision went the way it did, what the last attempt failed on, how you deal with your customers. A knowledge base turns that into something you can call up, and in combination with AI three things happen. Knowledge becomes shareable instead of being tied to individual heads. It keeps growing, because every clarification stays in there. And it becomes visible - you suddenly see what you actually have and where the gaps are. That is the difference between an AI that guesses politely and one that knows how you actually work.

After 28 years in the field - how do you stay close to current technology?

On my first day of training in 1998 we were told that learning would stay with us for life in this job. That constant learning is exactly what I love - I got to turn my hobby into my job. AI added energy on top: things that were not even thinkable back then can be tried out in a single evening today. So I build. This site is built with Astro, my day job is Vue, Nuxt and a headless CMS, and alongside that more than 25 of my own extensions for my working environment. Reading about a technology is not enough: if you have not put it into something that runs, you do not know it.

Do you still build websites for small businesses and clubs?

Yes - as a side business and on a small scale: few projects at a time, looked after for the long run, outside working hours and with my employer's knowledge. The projects on this page show what comes of it.

Why is your career shown as a git graph?

Because a list of positions leaves out half the story. My running portal ran for six years alongside my Siemens years, my side business has run alongside employment since 2018, and the move in 2024 was a branch with a merge back, not a break. A CV stacks all of that vertically and makes it look sequential. A graph shows what ran at the same time.

Contact

Let's talk.

Whether it's a question, a project or a chat about web development and AI - I'd love to hear from you. I am based in Rietberg, East Westphalia, and have preferred working remotely since 2020.