Notes from the machine room.
I'm Karthik Rajkumar. I write long-form about how machine learning works, the systems that carry it at scale, and the agents we are now building on top of both — each in its own publication, each with its own desk.
The masthead
Choose your desk
Three publications with one editorial standard: explain the idea properly, show the trade-offs, and leave you able to build it yourself.
Machine Learning
The Meridian
Models, maths and the craft of making them work.
Long-form notes on machine learning — from the intuition behind a loss function to what it takes to ship a model and keep it honest in production.
System Design
The Blueprint
How large systems are drawn, built and kept standing.
Architecture teardowns and design essays — queues, caches, consistency, and the trade-offs that decide whether a system scales or stalls.
Agent Architecture
The Dispatch
Field notes on building AI agents that actually finish the job.
Patterns for planning, tool use, memory and evaluation — the architecture behind agents that are reliable enough to trust with real work.
Fresh off the press
Latest stories
“Understand it deeply enough to draw it on a whiteboard.”
The house rule