About

Building systems
and the teams behind them.

I'm José María Cabeza Rodríguez — an Engineering Manager based in Berlin with 15+ years of experience delivering backend systems, distributed architectures, and high-performing engineering teams across France, Scotland, and Germany.

My story

My journey started in Madrid, where I studied Computer Science at Universidad Politécnica de Madrid and was selected — on academic merit — to do R&D at Teldat SA. That early taste of real-world engineering, writing communication systems and patching Debian kernels, set the tone for everything that followed.

From Madrid I moved to the south of France to join Amadeus IT, where I spent six years across three teams. I designed reporting infrastructure used by American Express and Airplus, built PCI-DSS-compliant integrations, and delivered a proprietary algorithm for Japan Airlines that reduced ticket coupon computation from O(n!) to O(n³) — cutting response times from minutes to under 100ms.

After a stint in Edinburgh working on banking transaction pipelines, I joined the Merchant Partner Account Infrastructure team in Berlin. I grew from Senior Software Engineer to Engineering Manager, and today I lead a team of 8 building the critical systems that power payment integrations for 1,700+ merchants weekly — handling 1.4M+ requests per week through services I designed and still evolve.

The shift into management wasn't a pivot — it was an extension. The highest-leverage thing I can do is make the engineers around me more effective. I never stopped being an engineer; I just became a different kind.

Experience

Sept 2020 — Present

Engineering Manager — Partner Account Infrastructure

Klarna·Berlin, Germany 🇩🇪

Lead a team of 8 (4 mid-level engineers, 2 senior engineers, 1 PM). Oversee security and quality of 7 critical services handling API integrations with 40+ distribution partners (Adyen, Mollie, Stripe, etc.). Spearheaded a major Stripe integration onboarding 1,700+ merchants weekly. Designed and implemented a global merchant tracking service handling 1.4M+ requests per week. Proposed and co-built a custom framework to decouple our main system from services and queues — enabling automatic retriggering, call prioritisation, and chaining, significantly reducing maintenance overhead. Conducted 40+ Java technical interviews and coached a Senior Engineer to Lead Engineer.

Sept 2018 — Sept 2020

Senior Software Engineer — Merchant Account Infrastructure

Klarna·Berlin, Germany 🇩🇪

Automated partner pricing setup, reducing manual work from 4 days to 15 minutes. Led migration from Salesforce to a custom in-house system across 3 services. Developed a KPI monitoring dashboard in Grafana to improve system performance tracking. Coached and mentored junior engineers, resulting in multiple promotions to Senior Engineer.

Dec 2017 — Aug 2018

Senior Software Engineer — Data Platform Team

NCR·Edinburgh, Scotland 🏴󠁧󠁢󠁳󠁣󠁴󠁿

Maintained and enhanced legacy banking transaction analysis pipelines using Java, Dropwizard, Cassandra, HBase, and Hadoop.

May 2015 — Nov 2017

Senior Software Engineer — Aftersales Pricing Orchestration

Amadeus IT Group·Sophia Antipolis, France 🇫🇷

Refactored Amadeus Ticket Changer, simplifying debugging and enhancement via XML-based configurations. Designed and implemented a proprietary discount coupon algorithm for Japan Airlines, reducing computational complexity from O(n!) to O(n³) — generating results in under 100ms (vs. minutes), avoiding the need for a new dedicated backend.

Jan 2014 — Jun 2015

Software Engineer — Issuance, Documents & Reporting

Amadeus IT Group·Sophia Antipolis, France 🇫🇷

Designed, architected and built the module responsible for gathering and managing reporting features across Amadeus products (Selling Platform, Sell Connect, Amadeus e-Travel Management), including integration with American Express and Airplus International.

Jun 2011 — Dec 2013

Software Engineer — Leisure Shopping

Amadeus IT Group·Sophia Antipolis, France 🇫🇷

Integrated Amadeus with American Express BTA, ensuring PCI-DSS compliance. Responsible as functional analyst and front-end developer for new rail market features for Trenitalia, SNCF, Swedish Rail, and DBahn in Selling Platform and Amadeus e-Travel Management.

Nov 2009 — May 2011

Software Engineer

Cystelcom·Madrid, Spain 🇪🇸

Led development of Veedia Seminar Portal for Polycom Inc. to facilitate remote video conferencing. Built an ICEfaces 2 web app for Helvetia Seguros to monitor trader activity in real time. Design and development manager for a Flash-based web application creating an Interactive Voice Response system via flowcharts for Vodafone Spain.

Jun 2007 — May 2009

UPM Scholarship — Programmer

Teldat SA·Madrid, Spain 🇪🇸

Selected on the basis of outstanding academic performance by the Telematics Laboratory of Universidad Politécnica de Madrid. Led modification of a Debian-based OS to automate marketing study installations. Designed, developed and maintained a communication system between two modules of marketing studies software using facial recognition via webcams.

Education

Sep 2003 — Sep 2009

M.Sc. in Computer Science

Universidad Politécnica de Madrid, Spain

Final Project: Web app to manage research group information — Honors

Jan 2008 — Sep 2009

Specialization in Web Computer Software

Universidad Politécnica de Madrid, Spain

Certifications & Courses

Certifications

13

Oracle Certified Java Programmer

Oracle · 2013

11

Oracle Certified Java Associate

Oracle · 2011

Online Courses

2025

Flux Step by Step — AI Influencers & Fanvue Models FAST

Udemy · Dominik Felber

2025

Realistic AI Images with Stable Diffusion & Fooocus

Udemy · Dominik Felber

2025

OKR Goal Setting 101

Udemy · Axel Ritterhaus

2025

Spring Boot 3, Spring 6 & Hibernate for Beginners

Udemy · Chad Darby

2020

React — The Complete Guide

Udemy · Academind

2019

CSS — The Complete Guide

Udemy · Academind

2017

Machine Learning Specialization

Coursera · University of Washington

2017

Machine Learning: Clustering & Retrieval

Coursera · University of Washington

2017

Machine Learning: Classification

Coursera · University of Washington

2017

Machine Learning: Regression

Coursera · University of Washington

2017

Machine Learning Foundations

Coursera · University of Washington

2016

Machine Learning

Coursera · Stanford University

2015

Data Analysis and Statistical Inference

Coursera · Duke University

Engineering principles

These aren't aspirational. They're the lens through which I evaluate every technical decision and engineering interaction.

01

Simplicity is a feature

Complex systems fail in complex ways. I ruthlessly cut scope and complexity. The best code is often the code you don't write.

02

Observability-first

You cannot debug what you cannot see. Every system I build ships with structured logging, distributed traces, and meaningful metrics from day one.

03

Strong opinions, loosely held

I form clear technical positions and defend them with data — but I change my mind when presented with better evidence. Intellectual integrity over ego.

04

Autonomy through context

The best teams don't need micromanagement. I invest in giving engineers deep context on business goals so they can make great decisions independently.

05

Ship, learn, iterate

Perfect is the enemy of shipped. I lean into iterative delivery, measure outcomes, and compound learnings. Momentum beats perfection.

06

Write more than you think

Writing clarifies thinking. RFCs, post-mortems, ADRs — documentation is not overhead. It is how knowledge outlives the people who had it.