Hi, I'm Michael
Fullstack Developer
Over a decade of experience in software development & consulting - creating clean, maintainable fullstack solutions with Spring Boot & Angular
About Me
Michael Wellner
- Fullstack Developer -
As a Fullstack Developer from Stuttgart, Germany, I build robust, modern backend systems with Spring Boot using Java or Kotlin. My work spans microservice architectures, clean domain models, event-driven integrations, moduliths and high-quality REST APIs. On the frontend side I deliver intuitive Angular applications with a strong focus on usability and maintainability.
With more than a decade of hands-on experience, I have worked across several industries (Automotive, E-Commerce, Finance, Healthcare) and built scalable systems based on Postgres/MySQL, Docker, Kubernetes (Dev), CI/CD pipelines and cloud-ready architecture patterns. I enjoy solving complex technical problems - but always with the goal of creating sustainable, long-term value.
At the moment most of my energy goes into AI-assisted development. I work with Claude Code every day and treat it as part of the toolchain rather than a gimmick: scaffolding services, refactoring older modules, writing tests and reviewing changes. What I find most interesting is where the limits are - which tasks an agent handles reliably, where a developer still has to make the call, and how you keep architecture and code quality intact when code is produced faster than it can be read.
A sabbatical in 2025 gave me the time for a proper tech refresh: Kotlin, Spring Boot 4, Kafka and OpenTelemetry, along with a closer look at Angular 19+ and Kubernetes, rounded off with the OpenTelemetry Certified Associate (OTCA) certification. That habit has stuck - I still believe in continuous learning, pragmatic engineering practices, and a developer culture built on collaboration, code reviews and shared standards.
I thrive in environments where people support each other, knowledge flows naturally, and modern tooling enables focused work. To maintain high concentration and minimize context switching, I often use the Pomodoro technique.
In the complex world of code, simplicity is the ultimate sophistication.
Fullstack Dev
Building scalable backends with Spring Boot (Java & Kotlin) and the Angular frontends that talk to them - one stack, from the database up to the browser.
DB & Messaging
Designing efficient relational data models with PostgreSQL or MySQL and implementing scalable event-driven architectures using RabbitMQ or Kafka for reliable asynchronous system communication.
DevOps
Orchestrating containerized applications with Docker and Kubernetes, streamlining delivery via automated CI/CD pipelines (e.g. Jenkins), and ensuring deep system observability through OpenTelemetry.
Tools
Fast, precise daily work in IntelliJ IDEA and Git, these days paired with AI-assisted development in Claude Code for scaffolding, refactoring and reviews.
Concepts
Keeping code alive long-term with Clean Code principles and automated tests (JUnit, ArchUnit), and keeping teams in sync with Scrum routines that people actually stick to.
Professional Journey
Fullstack Software Developer
VYDA GmbH | Remote / Münster
Fullstack development of a digital claims platform using Spring Boot with Kotlin for the backend and Angular/Nx for the frontend, deployed via GitOps on Kubernetes and monitored using OpenTelemetry. Day-to-day work is AI-assisted, with Claude Code as a fixed part of the toolchain for feature work and code refactoring.
Transition phase & sabbatical
Used the time for a full tech refresh and earned the OpenTelemetry Certified Associate (OTCA). Deepened my expertise in Kotlin, Spring Boot 4 & Spring AI, OpenTelemetry, Angular 19+ and Kubernetes, and took a first look at data science and data engineering.
Team Lead Software Development
sidion GmbH | Remote / Stuttgart
Team lead of an interdisciplinary development team, fostering an open and supportive team culture through regular meetings and informal virtual exchanges. Served as the main contact for both professional and personal matters, supported career development, and handled goal setting.
Senior Software Developer
sidion GmbH | Remote / Stuttgart
Contributed to complex client projects in the finance and healthcare sectors, focusing on the development of modern Java-based microservice applications. Supported architectural decisions, promoted clean code practices, mentored junior developers, and worked in agile Scrum teams using a broad technology stack.
Professional Software Developer
sidion GmbH | Stuttgart
Worked on various client projects across automotive, logistics, banking, and e-commerce sectors, focusing on developing modern Java-based microservice applications. Used a wide range of technologies, worked in agile Scrum teams, mentored junior developers, and emphasized clean code practices.
Junior Software Developer
sidion GmbH | Stuttgart
Contributed to a client project in the automotive industry, focusing on software development using Java, SQL, XML, and IBM DB2. Supported requirements engineering and worked with project management tools like JIRA and Confluence.
Junior Consultant Automotive Engineering
wontec GmbH | Weissach
Worked in product data management at Porsche AG, focusing on optimizing product data integration within the Volkswagen Group. Responsible for an interface between SAP and an IBM host, and developed VBA tools in Excel for project management and quality assurance.
Skills & Experience
Development
Frameworks & Libs
Tools
Concepts
DB & Messaging
Infrastructure
OS
I primarily develop on macOS for its great developer experience, but prefer Linux (Ubuntu/Debian) for server and container workloads.
Stuff
Other things I have picked up along the way
Recent Projects
MaverickWave
A lightweight, modern CSS framework for building responsive websites with elegance and speed.
After copy-pasting the same CSS into every side project for years, I finally built the framework I actually wanted to use.
Idently
A tiny, stateless, code-based Deno identity server with code login and a JSON client-user store.
Sometimes you don't need OAuth, Firebase, or Keycloak. You just want a damn code and a JWT.
versions
A bash script to display the version numbers of your tools.
I just want to see the version numbers of all my used tools with one command.
Blog Posts
Atomic Design in Angular: A Scalable Architecture for Modern Applications
Is your Angular project becoming unmanageable? It’s time to stop building pages and start building systems. In this deep dive, we explore Atomic Design - a methodology that breaks interfaces into Atoms, Molecules, and Organisms. We’ll apply this theory to a real-world Login scenario using modern Angular (v19+) features like Signals and Standalone Components, and show you how to enforce it at scale with Nx.
Spring Boot 4 - What’s New and Why It Matters for Developers
Spring Boot 4 (GA expected in November 2025) is built on top of the new Spring Framework 7 - and it’s more than a version bump. This release is a structural upgrade that modernizes how Spring applications are built, configured, and deployed. For developers running Java applications in production today, this version delivers meaningful improvements in startup performance, modularity, and developer experience.
Kotlin and Spring Boot for experienced Java developers - A practical introduction
After eight years of shipping services in Java & Spring Boot, I took over a week to really try Kotlin. I expected “Java but nicer.” What I found is a language that feels familiar in all the right places and surprisingly opinionated where it matters.
Data-Oriented Programming in Java - More Data, Less Magic
Data-Oriented Programming in Java promotes modeling data as immutable structures and separating behavior into services. With Java's record, sealed interface, and pattern matching, this approach becomes clean and powerful - enhancing readability, testability, and domain clarity compared to traditional object-oriented design.
Tired of Auth Overkill? Meet idently - Simple, Stateless Deno Identity Gets Smarter
At its heart, idently is my take on dead-simple, stateless authentication built with Deno. The core idea? Forget emails and passwords. Just give users a secret code. They send the code, they get a JSON Web Token (JWT) back.
MaverickWave - I finally published my own CSS framework
After countless false starts over the years, I'm excited to finally share MaverickWave with you - a lightweight, responsive CSS framework I've built for modern web development. This project represents not just code, but a personal milestone in my journey as a developer.
My Digital Handshake - Why I Built My Portfolio Page
My portfolio page at m1well.com isn't just a list of skills or a digital resume - it's my professional statement, a carefully crafted space designed to tell you who I am as a developer.