• Frank Neff
• 02 Sep, 2025

• architecture
• cto
• system-design
• onboarding
• frameworks

How to Map Your System Landscape in One Afternoon – The C1.5 Shortcut

You’ve just stepped into a new role – maybe as CTO, maybe as Head of Development – and as usual, the architecture is a maze or even completely missing. Documentation is outdated, knowledge is scattered, and no one holds the full picture. Without a map, you’re flying blind.

You could spend weeks reading thru confluence, readme and code, piecing things together, but there’s a shortcut:

In this post, I’ll show you how to map a “good-enough” system landscape in one afternoon using a lightweight, practical shortcut of the C4 framework I call C1.5.

• Frank Neff
• 12 Feb, 2025

• scaling
• strategy
• product
• architecture

The Scalability Trap: How Premature Technical Excellence Kills the Product

The “Build it right the first time” mantra has sunk more startups than bad code ever did.

I’ve seen it firsthand: One developer built his own message broker in PHP because ActiveMQ “didn’t fit his needs.” Another rebuilt Ansible in Perl to provision VMs. And the wildest one? Someone started designing a version control system on top of Elasticsearch because Git was “inefficient.”

These weren’t feats of brilliance. They were ego-driven distractions that added fragility, wasted money, and created zero customer value. And they all happened because leadership failed to ask the only question that matters: “How does this help the user?”

• Frank Neff
• 13 Oct, 2023

• enterprise
• architecture
• visualization
• systems

How to effectively visualize an Application Landscape in Enterprise Architecture

In enterprise & solution architecture, connecting boxes with arrows is an often used and overrated visualization from high-level, thru component architecture, down to data and class diagrams. However, to create a holistic view on systems, component diagrams are not enough! When it comes to analysis or transformation of a high-level application- or service-architecture, I prefer to draw an Application Landscape Diagram, which I would like to show and elaborate on in this post.

• Frank Neff
• 11 Sep, 2023

• oauth
• oidc
• security
• authentication
• authorization
• architecture

Securing isolated systems: Caveats of using plain OAUTH flows and how to solve them

While OIDC and OAUTH are well-known standards, they don’t fit every purpose “out of the box.” In businesses with special regulations like banking, health care, etc., non-functional requirements to auth can be challenging. Different solutions and ways were evaluated to create a new identity provider for a medical network. The first approach was “just” using simple OAUTH by its most famous Authorization Code Flow. Of course, it failed fast, and I’ll show why and how we solved it in this post.