The subagent that wrote its own jailbreak
A read-only agent produced a fully-formed jailbreak on its first turn. Nothing acted on it. Here is what happened, and what it says about how we scope agents.
Rutger de Knijf
Recent content on Rutger de Knijf
Latest posts
AI in the software development pipeline
Take the SDLC and put an autonomous agent everywhere you'd otherwise put a human. Where the slots are, how to fill them, and why the harness and the feedback loop matter more than the model.
The Checkup I Didn't Do
Every time a smarter AI model lands, run it over all your projects. I keep telling people that. Then I got three days of Fable, and didn't.
Terraform All The Way
If you're running Kubernetes, Terraform should be doing the application layer too.
The AI-Assistance Skyline
Definitely not just a colorful bar chart.
The Stages of AI Grief
I was watching my craft melt away like a block of ice in the sun. And then I came out the other side.
Make Every Problem Claude's Problem
When something annoys me twice, I make a folder, start Claude Code, and hand the problem over permanently.
My Claude Code Status Line
The full ccstatusline setup (config, custom widgets, and Model Intelligence score) that turns invisible AI state into glanceable awareness
Your AI Fuel Gauge
A status bar widget that proves you have enough tokens, so you stop worrying and start building
The 40% Rule
Why keeping your AI coding assistant's context under 40% makes it noticeably smarter
My AI Secretary
How I built a personal AI assistant from markdown files, MCP servers, and Claude Code. And what it actually feels like to use one.
My Pants Build Journey
Notes from onboarding a large monorepo to Pants Build and keeping my sanity intact.
On Backward Compatibility
Backward compatibility is a (sometimes) necessary evil that should be avoided whenever possible. Sounds simple, right?
On formatting in Google Spreadsheets
Formatting in Google Spreadsheets is a trap. Here's how to do it right.
"No, I just use vim"
On the cost of forgoing accelerators
I made an online Github Actions upgrader!
My first Javascript in at least 10 years
CICD trick to keep your dependencies up to date
Most developers know they should pin their 3rd party dependencies. I usually write Python, but this goes for any language. You don’t want to send your commit into CICD and have it be deployed with packages that are different from what you’ve tested it with locally. On the other hand, every day you lag behind with updating those dependencies you’re making doing that very thing in…
`internal_error` in Google Cloud HTTP(S) Load Balancing logs
Google HTTP loadbalancers are great. But this very undescriptive error threw me a curveball.
Limit your BigQuery costs with Terraform
BigQuery query costs can explode beyond acceptable limits. Add this resources to any Google Cloud project you manage with Terraform.
PostgreSQL benchmark over Cloud Proxy in GKE: socket vs port
Sockets are always faster, right? Right, let's check that quickly.
About
Rutger de Knijf. I've been fixing things since Windows 3.11.
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What hiring me looks like: infrastructure, software delivery, and AI-assisted development, on contract.