Freelancer · own company & client projects
PHP · Java · Agentic Engineering (since 2025)
Various client and own projects · 94+ software projects/year · 25k–35k LOC/day
fabian@agentic ~ cto
$ cat stack.manifest
Fabian Rossbacher Agentic Engineer
Graduate in Business Informatics (Dipl.) · coding since 1990
Agentic Engineering · Software Architect · CTO
since 1990: compile(source) · deploy(agents) · repeat ∞
Cursor Tokens 2025
125+ bn
Cursor Ranking Q4
Top 300
LOC / day
25,000–35,000
Projects / year with AI coding since 2025
94+
Coding since
1990
Developer mandates
10+
The 94+ projects per year figure covers client and in-house builds in agentic AI coding mode. Selected reference projects – from AmzRadar and the SEO jobs portal to Mallorca Zeitung, KeywordTool and URLradar – are documented on the SEO-DAY AI page.
Foundation
- Completed vocational training (IT/programming)
- Graduated: Business Informatics (Dipl.), RFH Cologne (2004–2008)
- Programming experience since age 8 (1990)
- Since 2025: agentic engineering as primary development mode
Agentic Engineering
- Agentic engineering with Cursor, subagents and automated dev pipelines
- 25,000–35,000 lines of production-ready code per day
- 94+ software projects per year – clients and own platforms
- Led a small dev team, now solo entrepreneur with an agent team
- Architecture, services, orchestrators, tests – end-to-end in the stack
- Cursor 2025: top 300 worldwide (Q4) – open book with 125+ billion tokens
Solo – with an agent team
I work as a solo entrepreneur. My team is made up of agents – no big office, but plenty of parallel terminals. All source code is created this way: for clients and my own projects, averaging 25,000 to 35,000 lines per day. Four machines, four Cursor instances, up to nine projects at once. Sounds like a lot? It is – so here is a quick peek behind the scenes.
- Solo entrepreneur – source code built together with the agent team
- 25,000–35,000 lines of production-ready code per day
fabian@agentic ~ workspace
Workspace recording from 2025: four machines running parallel Cursor sessions in a solo setup.
Cursor 2025 – Open Book Stats
In Q4 2025 I ranked among the top 300 Cursor users worldwide (top <0.1% of paying users). I published my full usage statistics transparently as open book – including billions of tokens consumed in peak development months.
- Top <0.1% worldwide – roughly top 300 of paying Cursor users (Q4 2025)
- 125+ billion tokens consumed in 2025
- 148,169 messages · 24,778 chats · 202 coding days
- Open book: all screenshots and analysis publicly available
Tech career
Reverse Retail GmbH
Interim CTO · e-commerce
Re-commerce (Buddy & Selly, Vite EnVogue) – marketing team, performance channels and affiliate restructured
crowdfox.com
Interim CTO
IT task force, AdWords API, checkout, tag engineering
ivu.de
Classic software development
Elasticsearch search: 100% performance gain
Rheinische Post
Freelancer · Java
CMS relaunch (rp-online.de) with 10-person team – software architecture, +100% SEO performance
singleboerse.de
Founder · development & operations
Built, operated and sold dating comparison platform (exit)
pironet GmbH
Freelancer · Java
Master data pool (today GS1 Germany) – software architecture, refactoring >3M LOC, +250% performance
SEO-DAY
Founder · conference platform
Built SEO conference (seo-day.de) and community from scratch
Stack & skills
Personal
Born
29/09/1982
Languages
German, English
Hobbies
Regatta sailing
On the side
On the side, I build communities in SEO and marketing with companies such as SEO-DAY GmbH. My main focus, however, remains the technical stack and source code.