Codeminer42's Engineering Blog
The Miners

I built an AI agent for our World Cup betting pool. She beat all of us.
Memory and context engineering for a long-running AI agent: how BETanIA got a diary, a mood, grudges, and a compaction strategy - and won our World Cup pool.
How “Your CFPs Aren’t Good” Became Five Approvals at RubyConf
In April 2025, Tropical on Rails, the Rails conference in São Paulo, said yes to one of our talks for the first time. A few months later, one of its…
How Far Can AI Self-Validate Rails Code?
A few weeks ago, I wrote Stop Reading AI Code, Start Measuring It: A Rails Playbook. The idea there was that if you stop hand-reviewing every line of AI-generated code,…
What Puma, Falcon, and Pitchfork teach you about Ruby concurrency
I went on a tour of Ruby concurrency while preparing a RubyConf talk on Ractors. Going in, I knew Puma, Falcon, and Unicorn. Coming out, I'd added Pitchfork to that…
My First Two Weeks as an Agentic Engineer
There's a version of this post where I tell you AI made me 10x more productive, everything clicked on the first try, and I'm now shipping software while sipping coffee…