16+ years
Experience & Curiosity
Backend engineering, new technology, and learning how different businesses work.
Available now
Freelance Senior Software Engineer & Architect
I solve tough backend challenges and build dependable systems.
I enjoy getting to the bottom of tricky bugs, learning new business domains, and building software alongside energetic teams. When legacy code holds you back or complex backend problems need solving, I bring experience, curiosity, and a hands-on mindset.
.NET & Java · Backend Engineering · APIs & Integration · Modernisation
Stefan Weyer
Engineering · Architecture · Leadership
What defines working with me
7+ years
Team Spirit & Leadership
I work directly with teams and enjoy helping junior engineers grow.
Root-Cause Analysis
Root-Cause Analysis
Following a problem through the system until the actual cause is clear.
Experience across e-commerce, tax, healthcare and veterinary software. I am happy to share further project details in a conversation.
What drives me
Curiosity, careful problem-solving, and genuine teamwork.
I step in where a new business domain, tricky bugs, and established software meet.
Backend Engineering
Robust APIs, dependable business logic, and maintainable systems built for the long haul.
Problem-solving & Modernisation
Tracking down elusive bugs, understanding root causes, and stabilizing legacy platforms step-by-step.
Rapid Domain Onboarding
Quickly grasping complex business processes across e-commerce, tax platforms, healthcare, and more.
Teamwork & Mentorship
Sharing knowledge, empowering junior engineers, and shipping clean code together with energy.
Projects
Selected projects
A few examples from backend engineering, modernisation, and systems integration.
Digital nutrition consulting platform
- Role
- Lead Full Stack Engineer & Software Architect
A new digital service required an integrated platform for booking, communication, administration and mobile use.
View project profileE-commerce and tax platform
- Role
- Lead Full Stack Engineer & Software Architect
Complex e-commerce and tax processes needed to be represented transparently, securely and extensibly in one web platform.
View project profileCloud-based practice management software
- Role
- Senior Software Engineer, .NET & Blazor
An established practice platform needed regulatory workflows and external integrations without destabilising existing operations.
View project profileApproach
Driven by curiosity, clarity, and collaborative spirit.
I work alongside your team – from the first bugfix to an architecture that holds up in daily use.
- 01
Dive In & Understand
Eagerly learning new business domains, complex processes, and team dynamics with an open mind.
- 02
Understand Root Causes
Investigating persistent bugs instead of applying superficial patches.
- 03
Deliver Hands-on
Engineering, testing, learning, and shipping clean APIs alongside the team directly in the code.
- 04
Empower & Stabilise
Transferring knowledge, documenting key decisions, and ensuring lasting operational stability.
Career path
Technical leadership built on engineering practice.
I moved from .NET engineering through team leadership and a CTO role into freelance work. I still spend a lot of time in the code.
View career timeline →- 01Java & .NET Software Engineer
- 02Senior Engineer & Project Lead
- 03Team Lead & Technical Director
- 04CTO & Lead Developer
- 05Freelance Senior Software Engineer & Software Architect
Contact
Has your backend grown difficult to change, or is the project stuck?
I help when bugs are hard to trace, new integrations are needed, or the team needs someone to connect architecture with hands-on delivery.
A good fit when …
- an established backend has become difficult to change
- several systems or APIs need to work together
- technical ownership needs to be shared or clarified
- Available now
- Conversations welcome now
- Remote and hybrid
- Mönchengladbach and Düsseldorf