howardjohn's blog

In my last post, The hidden cost of mpsc channels, I discussed a common pitfall with Rust mpsc channels using more memory than intuitive (and subsequently got roasted by people pretending they read the footnotes of the documentation of every transitive de…

Recently I have been spending a lot of time analyzing and optimizing memory usage in our Rust reverse-proxy, agentgateway.

When trying to use any Kubernetes CRD (or even core types) I am pretty much always pulling up a reference doc of some sort to see what fields are available and what they do.

This is part two of a series.

After years of working on a project running our own testing infrastructure, I have been working on Agentgateway utilizing the free GitHub Actions runners.

The go.mod file contains a mandatory go <version number> directive.

With the retirement of ingress-nginx I've seen a lot of frustrations with Gateway API migrations due to differences in some of the resource models.

This is part one of a series.

When building out Agentgateway, we had a desire to introduce an embedded expression language to allow users to write custom logic to be evaluated at runtime.

Recently I had a need to run a bunch of steps in a bash script, with interweaved dependencies for a CI pipeline.

As I ramp up coding agent usage, I found myself wanting to share the Rust build cache across multiple copies of the same project (via git worktrees) to avoid multiple-minute cold builds.

The new Pod Certificates feature in Kubernetes v1.35 promises to "drastically simplify service mesh architectures".

While typical HTTP request routing happens based on the request headers/path, sometimes routing based on the body is useful.

How I run Agentgateway on my homelab setup.

Common Expression Language (CEL) is a great little language for embedding users' custom logic into an application.

An often overlooked part of the Rust license is that within a year of usage, users are required to make a comparison to their (previously) favorite language.

I've spent the majority of my career building Istio's control plane, Istiod, with an emphasis on making it highly performant and scalable.

In the past few years, CPUs have gotten really fast.

AI workloads introduce new requirements on networking infrastructure, but the same core requirements that service meshes solve not only remain, but are exacerbated.

Gloo Mesh’s ambient multi-cluster mode sets a new benchmark for scalability.

Go 1.24 introduces new support for "Tools", which allows easy consumption of tools (which are written in Go) as a dependency for a project.

Is it a per-node proxy?

Reimagine service mesh with Istio’s ambient mode—lightweight, efficient, and scalable.

A deep dive into the termination behavior of Istio ambient mode and how it impacts your applications.

How Istio ambient mode brings an enterprise-ready service mesh to Amazon ECS.

How ambient achieves massive scale without toil.

When we first started designing what eventually became Istio ambient mode, there were many directions we explored, both in terms of implementation, and what our goals were.

Over 2 years ago, I started working on some ideas to build better Kubernetes controllers.

External Blog Post.

Tools to create reproducible development environments are basically everywhere these days, from Development Containers to Nix wrappers to questionable Docker hacks.

JetBrains IDEs (IntelliJ, GoLand, etc) have a nifty feature called Language Injection that lets you get full language features when a language is embedded within another.

How Istio ambient mode greatly simplifies and improves egress gateway use cases.

How Gloo mesh brings HTTP observability to your mesh, without compromises.

An overview of options to deploy mTLS on Kubernetes

Istio's installation has a long, winding, complex history, leading to an interesting current state.

Zero trust architectures should not treat nodes as highly privileged components.

Core problems with the API make it a challenging to use in a secure, scalable manner.

go run bash-script@latest

How we built a best-of-both-worlds experience with Istio ambient mode.

Installing Istio... hard could it be?

Does Istio ambient introduce a SPOF?

How I iterate on Grafana dashboards

Sidecarless?

How Istio tests its networking proxy without Kubernetes, Docker, or root.

tl;dr: it just works

Like most other Kubernetes controllers in, Istio is written in Go and relies on the client-go library.

Rage bait for YAML templating haters

Which features I recommend using, or not using, in Istio

In Analyzing Go Build Times, I went over how to analyze and understand Go build times, and what factors impact build times.

Exploring an extreme service mesh architecture to maximize extensibility.