Last time I wrote about why I keep saying yes to open-source mentorship. This post is the how: specifically, how to be a mentee in 2026. I’ve spent the last few years on the mentor side of CNCF LFX LFX Mentorship — the Linux Foundation’s structured mentorship program. Cohorts run quarterly, projects are scoped to ~12 weeks, and mentees receive a stipend. , Google Summer of Code ( GSoC A Google-funded program where students contribute to open-source projects over the summer, paired with mentors from those projects. ), and GoBridge, through Thanos, Prometheus, and now OpenTelemetry projects. Every cohort I’ve run, the same questions keep coming up from people who want to apply but don’t know how to start. ...

There’s a moment that keeps happening to me. Someone I mentored two or three years ago shows up in a SIG call, on a maintainers’ list, on a stage at KubeCon. They’ve shipped something I couldn’t have shipped alone. They’re answering questions I once answered for them. And the part that gets me: they’re already mentoring someone else. That moment is the thing. why why It’s also the only honest answer to “why do you keep doing this when it’s not your job?” The loop closes, and you get to watch. ↩ Everything else I write here is a footnote to that moment. ...

Every now and then a project surprises you by remembering something you said years ago. This week was one of those weeks. A talk I gave at PromCon Online 2020 — The Zen of Prometheus — has quietly become part of the official Prometheus documentation. I am still sitting with it. Where it started The talk was born in the strangest year of my career. PromCon 2020 was online, like everything else. I was a few years deep into running Prometheus in anger, collecting scars from instrumenting services that didn’t want to be instrumented and writing alerts that kept me up at night for the wrong reasons. I wanted a way to package those lessons that wasn’t another forty-slide deck of bullet points. ...

A Loose Cable That Broke Physics In 2006, a team of physicists began building the OPERA experiment — a 730-kilometer underground tunnel from CERN in Switzerland to Gran Sasso in Italy, designed to measure the speed of neutrinos. Five years of construction. Roughly 100 million euros. The most rigorous experimental physics on the planet. In September 2011, the results came back. Neutrinos were traveling faster than the speed of light. The team had just broken the laws of physics. ...

This post expands on the FOSDEM 2026 Go Devroom talk I co-presented with Hannah S. Kim. The talk, demo code, and all benchmark scenarios are available in the fosdem-2026 repository. The Problem Go is one of the best languages for building production backend services. It compiles to native binaries, has excellent concurrency primitives, and produces predictable performance characteristics. But when it comes to auto-instrumentation — adding observability without modifying source code — Go is uniquely difficult. ...