gpg, gnupg, encryption, pgp, public key cryptography

GPG explained: from first key to daily use

GPG is one of those tools everyone “should learn someday” but nobody wants to. The documentation is overwhelming, the terminology confusing, and the error messages cryptic (pun intended). But GPG is also essential. It’s the foundation for pass, for signed git commits, for encrypted email, and for verifying software downloads. If you’re serious about security, you can’t avoid it. This is the guide I wish I had when I started. What is GPG actually? GPG (GNU Privacy Guard) is an implementation of the OpenPGP protocol. It does two things: ...

January 6, 2026 · 9 min read · Tom Meurs
Kubernetes RBAC access control visualization

Kubernetes RBAC: Least Privilege in Practice

When everything has cluster-admin, nothing is secure. Kubernetes RBAC (Role-Based Access Control) exists to answer one question: who can do what to which resources? Most clusters answer incorrectly: “everyone can do everything.” This isn’t just a security problem — it’s a resilience problem. When a service account gets compromised, how much damage can it do? When someone runs the wrong command, what’s the blast radius? Least privilege limits that radius. ...

August 19, 2025 · 7 min read · Tom Meurs
Falco runtime security monitoring visualization

Runtime Security with Falco: Detect Suspicious Behavior in Your Cluster

You scanned your images with Trivy. You enforced policies with Kyverno. Your workloads have cryptographic identity via SPIFFE. But what happens after deployment? What if a container gets compromised at runtime? What if an attacker exploits a zero-day? Prevention isn’t enough. You need detection. Falco is a runtime security tool that monitors system calls in your cluster. It sees everything containers do — file access, network connections, process execution — and alerts when something looks wrong. ...

August 7, 2025 · 8 min read · Tom Meurs
SPIFFE workload identity visualization

SPIFFE and SPIRE: Zero Trust Service Identity

How does Service A know that Service B is actually Service B? In traditional networks, we trusted network location. If traffic came from the right IP, it was legitimate. Zero trust killed that assumption. Now every service must prove its identity, every time, regardless of network position. SPIFFE (Secure Production Identity Framework for Everyone) is a standard for service identity. SPIRE is its production-ready implementation. Together, they give every workload a cryptographic identity — automatically, without static secrets. ...

July 26, 2025 · 7 min read · Tom Meurs
Kyverno policy governance visualization

Kyverno Policies: Governance as Code for Kubernetes

Rules that exist only in documentation don’t get followed. Rules enforced by computers do. Kubernetes gives you incredible flexibility. Every team can deploy whatever they want, configured however they like. This freedom becomes chaos without guardrails. Kyverno is a policy engine for Kubernetes. It validates, mutates, and generates resources based on policies you define — as Kubernetes-native YAML. Why Kyverno? There are multiple policy engines: Open Policy Agent (OPA) with Gatekeeper, Kyverno, Kubewarden. I chose Kyverno because: ...

July 14, 2025 · 7 min read · Tom Meurs