Martin Stühmer — CTO, Enterprise Architect & DevOps Engineer

Who I Am

I’m Martin, CTO at Integrated Worlds GmbH in the Stuttgart region. I’ve been writing production .NET code since Framework 2.0 — back when SOAP was still considered modern and ORMs were a heated debate. A lot has changed since then. My opinions have changed too, usually because I was wrong about something.

Before Integrated Worlds, I was Director of Consulting Services at CGI, leading teams through architecture decisions and digital transformation projects across multiple industries. These days I set technology strategy and stay close enough to the code to feel the consequences of those decisions firsthand.

I’m a Microsoft Certified Trainer and IHK-certified instructor, maintain several open-source NuGet packages, and write about what I’ve actually learned rather than what sounds good in theory.

LinkedIn · GitHub · Bluesky

What I Know Well

Nearly two decades of production work leaves marks. Here’s where I’ve built up depth and, frankly, strong opinions:

.NET and C# — I’ve tracked this ecosystem from the framework era to .NET 10. Source generators, Roslyn analyzers, performance engineering, testing strategies, static analysis. I know what actually improved over the years and what just changed names.

Cloud-native architecture on Azure — AKS at scale, multi-cluster networking, zero-downtime upgrade strategies, cost governance, observability. I’ve spent enough time in Azure to know the gap between what it can do and what you should actually use.

DevOps and supply-chain security — GitHub Actions, dependency management, container security, Bicep-based infrastructure compliance. The organisational side matters as much as the tooling.

Application security and privacy — Azure Key Vault, managed identities, GDPR-relevant .NET patterns, data minimisation, AI coding tool content exclusions. Security that works in practice, not just in architecture diagrams.

Engineering culture — What AI coding assistants actually change about software quality (less than the hype, more than the skeptics admit), how to introduce static analysis without poisoning team morale, and when “best practices” are earned principles versus cargo-cult repetition.

How I Work

As CTO I stay close to the code. I write, review PRs, debug production issues, and mentor — because technology leadership that operates purely from a distance eventually loses touch with the real cost of decisions.

As a trainer I focus on fundamentals that outlast the current framework cycle. Static analysis, testing discipline, performance patterns, maintainable architecture. The things that prevent fires, not just the things that look good in a job posting.

As an open-source maintainer I publish packages that solve problems I’ve hit repeatedly. Knowing that strangers depend on your code is one of the better ways to raise your standards.

What I’ve Learned the Hard Way

I’ve over-engineered systems that should have been simple. I bet on Silverlight and WCF. I built “flexible” architectures that were really just complicated ones. I’ve shipped code I’m not proud of.

Here’s what held up after all that:

Quality isn’t optional — analyzers find bugs in milliseconds, tests prevent regressions, and neither is slower than a production incident
Fundamentals outlast frameworks — the patterns and principles stick around long after the tools are deprecated
Context beats dogma — “best practices” always depend on your team, domain, and actual constraints
Evidence beats intuition — measure, benchmark, validate; don’t just decide
Pragmatism wins — architecture that ships beats architecture that’s perfect on paper

What I Write About

Everything here comes from production systems and real teams, not documentation rewrites. I’m skeptical of buzzword-driven development and allergic to advice that’s never been tested under load or deadline. If something doesn’t hold up, I’ll say so.

The topics I keep returning to: .NET and C# performance and evolution, Azure and AKS architecture decisions, DevOps and supply-chain risk, application security and GDPR implementation, what AI coding tools actually change (and what they don’t), and the economics of technical debt and code quality.

I write for developers, architects, and operators who maintain production systems and care about getting it right — not just getting it shipped.

The code you create is a valuable legacy, so it’s important to build it carefully.

Published blogs

AI Code Review Is a Sycophant: Why It Always Approves

AI code review tools are genuinely useful for catching syntax errors, obvious bugs, and common anti-patterns. They are also systematically unable to tell you that the feature you built was the wrong call, that the abstraction is off, that the naming reveals confused thinking, or that the correct review comment is “delete this.” Here is what AI reviews find, what they miss, and why human judgment still has no substitute.

Source Generators: The Build Performance Killer

Source generators are powerful. They are also running on every single build, blocking IntelliSense, breaking Hot Reload, and multiplying their cost across every target framework you support. Nobody mentions this in the getting started guides. Here is how to measure the damage, find the culprits, and decide when source generators are actually worth it.

.claudeignore Doesn't Exist. Here's What Does.

Claude is indexing your bin/ and obj/ directories right now. You asked it how to stop that. It told you about .claudeignore. You added it, committed it, and felt responsible. There is just one problem: .claudeignore does not exist. Claude invented it, the internet spread it, and your secrets were never protected. Here is what actually works.

Your Privacy Docs Are Fiction: Let's Fix That with .NET CLI Tools

Spreadsheet-based privacy audits examine yesterday’s system while today’s code deploys undocumented PII. Build .NET CLI tools that discover all personal data, catch expired consents, and verify deletions. Then fail builds when compliance breaks.

Security Tests That Prove Themselves

Your security tests run. They pass. But can you prove when they ran and against which code version? Most security testing lives in Word documents, Postman exports, and screenshot folders on SharePoint. The tests themselves might be valid. The evidence trail is not. This article shows how to build CLI-based test suites using xUnit and WebApplicationFactory that generate their own proof: structured logs with timestamps, commit hashes, and correlation IDs captured automatically in CI/CD pipelines. No more quarterly reports that could have been written yesterday. Instead, 847 test executions across 23 deployments, each linked to a specific commit and preserved for 90 days.