Tutorial

This is the third article in my “Back to Basics” series. The goal is simple: take something modern engineers interact with daily through abstractions, and explain what is actually happening underneath. In the first article, I hardened an SSH daemon and explained why the defaults are insecure. In the second, I showed that containers are ordinary Linux processes wrapped in namespaces and cgroups. This article applies the same approach to TLS: strip away the abstractions, read the raw structures, and understand what the tooling is doing on your behalf. ...

In today’s fast-paced tech landscape, it’s common to find incredibly talented engineers mastering complex orchestrators like Kubernetes or crafting intricate Infrastructure as Code solutions. We’re living in an era of high-level abstractions, which is fantastic for productivity. However, this focus on the ’new and shiny’ can sometimes lead us to overlook the foundational bedrock upon which everything is built. It might seem a bit old-school to write a blog post about hardening SSH in 2025. Yet, these ‘basic’ skills are more critical than ever. In a world of ephemeral infrastructure and complex supply chains, securing the front door to our systems remains a non-negotiable first step. ...