Jonas Holtkamp
Software Engineer
Cloud-native backend systems, distributed architectures & containerised infrastructure. Over a decade building things that scale.
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About
Over a decade in. Still enjoying it.
I'm a backend-focused software engineer with deep experience in cloud infrastructure, distributed systems, and the kind of platform work that keeps everything running but rarely makes it onto a slide deck.
At Senacor, I spent nine years as Lead Developer — leading a feature team inside an agile delivery setup. That means I know how to design architecture and how to work with the people implementing it. I thrive in collaborative environments and I've been told I'm easy to be around.
Currently at codejoi, working as an SRE and cloud engineer embedded in a platform team in the fintech sector.
Agentic AI coding tools are part of how I work — Claude Code specifically. I've found that knowing when not to trust it is at least half the skill, and a decade of engineering judgement tends to help with that.
Outside of work, I love the outdoors — long distance running with a passion for marathons, hiking, and gravel riding.
I care about the work I take on. I'm drawn to companies with a genuine commitment to ESG and social responsibility.
I don't have a LinkedIn. This is it.
Experience
2025 — present
Software development consultancy. Focus on cloud infrastructure, platform engineering, and application development.
2016 — 2025
IT consulting and digital transformation for clients in financial services and automotive. Designed and implemented cloud-based microservice architectures, led a team of junior and senior developers, and owned technical decisions end to end — architecture, code, people, and stakeholders.
2013 — 2016
IT service provider for the German savings bank financial group. Java engineer on the core banking system, focused on credit processes. Where I learned my ropes.
Most Proud Of
Automotive After-Sales Platform
2022 — 2025 · Automotive
The project started as a migration — a legacy 3270 mainframe terminal used for capacity management and product information in the after-sales domain, maintained by a single engineer approaching retirement. We replaced it with an internet-facing, cloud-native web application that anyone could use without training.
What I'm most proud of isn't the technology. It's what the platform became. After the initial migration, we expanded to five locations, absorbed the OEM's internal employee leasing programme, and opened the platform to end users managing their own vehicle handovers and returns — a user group that would never have touched the old system.
We went from a near-frozen codebase to releasing every three weeks. From mainframe hardware to AWS. From one maintainer to a team of five. It was the first time I led a team of that size, and it's the project that best represents how I like to work — close to the people, close to the problem, and building something that outlasts the engagement.
Selected Projects
From my time at Senacor.
2025 — present
Fintech
European Payments Platform
- — Site reliability engineering for a high-availability, mission-critical payments platform.
- — Cloud infrastructure management and platform engineering for distributed payment services.
- — Observability, monitoring, and incident response across production environments.
- — Infrastructure as code and Kubernetes cluster operations at scale.
2022 — 2025
Automotive
Automotive After-Sales Platform
- — Led a team of 4–5 engineers through the modernisation of a legacy mainframe terminal to an internet-facing, cloud-native web application.
- — Expanded to 5 locations and migrated the OEM's internal employee leasing programme, opening the platform to non-trained end users for the first time.
- — Took the codebase from near-frozen to a 3-week release cadence; migrated infrastructure from mainframe hardware to AWS.
2020 — 2022
Financial Services
Multi-Channel Banking Platform
- — Designed and implemented the architecture for a multi-channel online banking platform on Google Cloud.
- — Built a distributed microservice layer covering product and partner domains, with a focus on scalability and resilience.
- — Implemented a data integration layer handling both event-driven and batch processing workloads.
- — Contributed to internal shared libraries, standardising logging, authentication, and database access across teams.
2018 — 2020
Financial Services
Private Banking Application
- — Co-designed an event-sourced CQRS microservice architecture for a private banking platform.
- — Built and operated microservices on a Kubernetes-based (OpenShift) infrastructure.
- — Developed greenfield data models and services in Kotlin, backed by Redis and MongoDB.
Skills
Languages & Runtimes
Cloud & Infrastructure
Data
Messaging & Streaming
Observability
CI/CD
Practices
Contact
Let's talk.
Whether you have a project in mind, want to talk shop, or just want to say hello — my inbox is open.
hello@jonasholtkamp.dev →