iiinova — where your digital self keeps evolving

Felix Geisendörfer @felixge.de · 4h

I assume you considered pi or other harnesses? Anything keeping you on codex?

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Felix Geisendörfer @felixge.de · 10/09/2026

Congratulations! To both the Go team, as well as to you! This is fantastic news for the community. 🎉❤️

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thepudds @thepudds.bsky.social · 10/09/2026

I’m very, very happy to share that I have just joined the core Go team at Google to work on the Go runtime and compiler! I’ve been pitching in as an external contributor since 2018, but now my very enjoyable hobby is becoming my day job 😅 (Also, my name is PJ 👋)

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Felix Geisendörfer @felixge.de · 02/06/2026

If anybody with connections to the V8/Chrome team is reading this, my colleague Attila is trying to find a reviewer for a patch to improving profiling. Many thanks in advance for any leads 🙇🏻‍♂️ chromium-review.googlesource.com/c/v8/v8/+/78...

chromium-review.googlesource.com

Gerrit Code Review

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Felix Geisendörfer @felixge.de · 06/05/2026

PSA: Green Tea GC in go1.26 is incredible 🚀 This is what we saw for two big Go services. We'll try to gather more data and share it soon.

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Felix Geisendörfer @felixge.de · 04/05/2026

I just published a proposal for a new RSS profile type for Go. It aims to solve the issue that the heap profile typically shows < 50% of process RSS, which is very confusing. It should also help to quickly identify when memory usage is dominated by cgo. github.com/golang/go/is...

github.com

proposal: runtime/pprof: add a rss profile type · Issue #79179 · golang/go

This is a proposal to introduce a new "rss" profile type to runtime/pprof to provide Go users with a holistic breakdown of their program's memory usage. Problem Statement As part of incident respon...

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Felix Geisendörfer @felixge.de · 30/04/2026

I have a custom extension that tries to prevent accidents, but for use cases requiring stronger security I spin up dedicated VMs.

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Felix Geisendörfer @felixge.de · 30/04/2026

In exchange for 18 minutes of your time, you can get an elevator pitch about why you should be using pi (instead of claude) and perhaps more importantly, one of the sanest takes on using AI effectively 🔥 www.youtube.com/watch?v=Rjfb...

youtube.com

Building pi in a World of Slop — Mario Zechner

YouTube video by AI Engineer

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Felix Geisendörfer @felixge.de · 31/03/2026

Arguably flame graph screenshots are not the best context encoding, but yes - it works sometimes!

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Felix Geisendörfer @felixge.de · 31/03/2026

And of course, if you're looking for a vendor, Datadog has you covered. You can join the preview for the OpenTelemetry eBPF profiler here: docs.datadoghq.com/profiler/ena...

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Felix Geisendörfer @felixge.de · 31/03/2026

If this sounds interesting to you, and you'd like to get an early taste of the troubleshooting powers of the Profiles Signal, please check out our post on the OpenTelemetry blog for more details: opentelemetry.io/blog/2026/pr...

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Felix Geisendörfer @felixge.de · 31/03/2026

Profiles (unlike logs, metrics and traces) are directly linked to code. Florian Lehner and I demonstrated this at KubeCon by using profiling to root cause an incident caused by a coding agent. But the reverse works too: agents can use profiles to troubleshoot or optimize code.

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Felix Geisendörfer @felixge.de · 31/03/2026

The OpenTelemetry Profiles Signal is now in Alpha 🚀 This is a big step towards making Continuous Profiling in production available to the whole industry. And given the rise of AI coding, this couldn't come at a better moment in time ... 🧵

Florian Lehner and Felix Geisendörfer presenting "The Fourth Pillar Arrives: OpenTelemetry Profiling Alpha in Action" at KubeCon EU

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Paul Bauer @bauer.codes · 25/03/2026

People that strip debug symbols are not to be trusted.

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Felix Geisendörfer @felixge.de · 22/03/2026

I’m headed to KubeCon Amsterdam where I’ll be talking about the otel profiling signal graduating to alpha stability. HMU if you want to chat about otel, go, o11y, profiling or anything else. I’m in town until Thursday night.

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Felix Geisendörfer @felixge.de · 11/03/2026

+1 I don't see any good reason for introducing a new term exclude. But git UX is abysmal in general. I exclusively use jj as a frontend these days. But the .git/info/exclude hack still applies :)

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Felix Geisendörfer @felixge.de · 10/03/2026

.git/info/exclude is one of my favorite git features, but I'm always surprised when I talk to people who never heard about it. It basically allows you to add stuff to .gitignore without modifying the file. Great for ad-hoc ignoring some files created during debugging.

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Felix Geisendörfer @felixge.de · 07/03/2026

I used vim exclusively for 10+ years. But when LLMs came up, I ditched it for VS Code and later Cursor as it was the path of least resistance. But given the advancements of claude et al, it's time to go back. neovim + tmux + jjui - let's go.

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Johannes Bechberger @mostlynerdless.de · 13/02/2026

Redact sensitive data from Java Flight Recorder and JVM crash logs with jfr-redact, a tool for safely sharing profiling and error files: mostlynerdless.de/blog/2026/02...

mostlynerdless.de

Redacting Sensitive Data from Java Flight Recorder Files - Mostly nerdless

Redact sensitive data from Java Flight Recorder and JVM crash logs with jfr-redact, a tool for safely sharing profiling and error files.

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Felix Geisendörfer @felixge.de · 06/01/2026

If I had to guess, they want to avoid triggering the hook when the user is still actively watching the window. But IMO that would be better solved using terminal focus tracking 🤔

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Felix Geisendörfer @felixge.de · 06/01/2026

Just spend like 20 minutes debugging why claude code notifications don't work. Turns out they fire after a hard coded 60 second timeout. I don't get it, I thought I'm supposed to feed this thing with input as fast as possible? github.com/anthropics/c...

github.com

[FEATURE] Configurable timeout for idle_prompt notification hook · Issue #13922 · anthropics/claude-code

Preflight Checklist I have searched existing requests and this feature hasn't been requested yet This is a single feature request (not multiple features) Problem Statement The idle_prompt notificat...

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Jeff Dean @jeffdean.bsky.social · 19/12/2025

My colleague Sanjay Ghemawat & I have done a fair bit of performance tuning of various pieces of code. We wrote an internal Performance Hints document ~2 years ago as a way of identifying some general principles & we've recently published a version of it externally. Doc: abseil.io/fast/hints.h...

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VLDMR VRNKN @vladimir.varank.in · 15/12/2025

Profiling Request Latency with Critical Path Analysis, @felixge.de @ GopherCon 2025 www.youtube.com/watch?v=BayZ...

youtube.com

GopherCon 2025: Profiling Request Latency with Critical Path Analysis - Felix Geisendörfer

YouTube video by Gopher Academy

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Felix Geisendörfer @felixge.de · 16/12/2025

The talk @florianl.bsky.social and I submitted has been accepted at KubeCon 2026 in Amsterdam. 🎉 Small wrinkle: The talk says that the profiling signal is in alpha … which is not true yet. Fear driven development will continue until reality and talk description are aligned!

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Felix Geisendörfer @felixge.de · 10/12/2025

A small productivity hack I use every day. gist.github.com/felixge/ce96...

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Anton Zhiyanov @antonz.org · 26/11/2025

Accepted! Go 1.26 will introduce per-state goroutine metrics: running, waiting, in syscalls, etc. Developers can use them to catch problems early without needing full traces. antonz.org/accepted/gor...

antonz.org

Go proposal: Goroutine metrics

Export goroutine-related metrics from the Go runtime.

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Nick Ripley @nsrip.com · 23/11/2025

Small contribution just before the Go 1.26 freeze: go.dev/cl/610815 removes the hard-coded 100ms sleep from the CPU profiler for most platforms. This will make it more efficient and unblock deeper call stacks. As a bonus, uncovered and fixed an 8 year old bug in the profiler go.dev/cl/722940 :)

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Michael Knyszek @michael.express · 20/11/2025

My talk from GopherCon 2025 about Green Tea is up on YouTube! www.youtube.com/watch?v=gPJk...

youtube.com

GopherCon 2025 - Advancing Go Garbage Collection with Green Tea - Michael Knyszek

YouTube video by Gopher Academy

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Felix Geisendörfer @felixge.de · 28/10/2025

actually, almost the same, the trunk parent is missing, but that’s okay if x is a descendant of trunk I guess?

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Felix Geisendörfer @felixge.de · 28/10/2025

You can do that in one step if you run: jj parallelize x::w same as jj parallelize x::w jj new trunk x n p w

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Neal Lathia @neallathia.bsky.social · 25/10/2025

"It has, with generative code, become harder and harder to strive towards the lions because the models produce code that is, quite literally, mid" - beautiful post by @vickiboykis.com newsletter.vickiboykis.com/archive/i-wa...

newsletter.vickiboykis.com

I want to see the claw

I respect quality software and the people who write it. And, I’ve invested years of my life in working on becoming one of these people (even if the journey...

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Felix Geisendörfer @felixge.de · 24/10/2025

Thank you for all your great work on this ❤️

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Steve Klabnik @steveklabnik.com · 22/10/2025

I see a future in #jj-vcs: steveklabnik.com/writing/i-se...

steveklabnik.com

I see a future in jj

Blog post: I see a future in jj by Steve Klabnik

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Felix Geisendörfer @felixge.de · 30/09/2025

I'd love to join one of these again soon, but I'm playing beach volleyball during that time. But usually I play Fridays, so it should work next time.

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Felix Geisendörfer @felixge.de · 28/09/2025

Watching "stupid jj tricks" from JJ con 2025 live right now. Tune in: www.youtube.com/watch?v=WWNh...

youtube.com

JJ Conference 2025

YouTube video by GerritForge TV

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Felix Geisendörfer @felixge.de · 17/09/2025

I need to start a critical path analysis art gallery soon. The kind of stuff goroutines get up to behind the scenes can be truly fascinating.

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Felix Geisendörfer @felixge.de · 17/09/2025

Two amazing time savings here: a) Tracing the call paths of a bunch of runtime functions to a function I know exists, but don't know the name of ("does network wakeup"). b) Writing the final analysis with code snippets and links to the Go code (permalinks at the right Go version). This is fun.

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Felix Geisendörfer @felixge.de · 17/09/2025

I'm starting to get better at leveraging AI agents for the kind of low-level stuff I'm doing sometimes. Example: Asked opus to explain some runtime internals, and then turn the analysis into a nice human-readable markdown output that I can use to explain a code change I'm making to a colleague.

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Go @golang.org · 16/09/2025

Hi folks, it’s survey time! We’d love to learn more about how you use Go and what could be improved. Share your feedback via our annual developer survey at google.qualtrics.com/jfe/form/SV_.... It should take 10 - 20 minutes to complete, and will be open through September 30. Thank you! #golang

google.qualtrics.com

Go Developer Survey 2025

Share your feedback about developing software with Go.

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Ari Arnbjörnsson @flassari.bsky.social · 11/09/2025

Profile.

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