Hello, world.

This is the first post on chrisfruit.dev — a personal site, mostly engineering notes from the seat I’m in: founding engineer at Ronja, shipping an agentic co-worker for mid-market companies. Before that, three years at Northvolt building software for Europe’s first gigafactory.

What I expect to write about:

• Agents and tool design — what I’m learning building a serious MCP-based tool framework in production. Tool contracts, decoder patterns, when to refuse vs. when to do.
• Forward-deployed engineering — notes from the customer side of the table.
• Industrial software — what factory floors teach you that pure web work doesn’t.
• Everything else — rugby, books, the occasional run.

Posts will be terse. The thing I want most from a personal blog is an excuse to think one level deeper about something I’m already doing. If you’re reading this — thanks. The RSS is at /rss.xml.