Waltteri
@waltteri.net
Finished a MSc in CS at University of Helsinki 🎉 Senior SWE at Cactos, battery energy storage systems. Previously Senior SWE at Garden, SRE at Webflow.
Recreational computer graphics, Rust, photography, cycling.
He/him. Mastodon (Twitter) @anotherwalther
Recreational computer graphics, Rust, photography, cycling.
He/him. Mastodon (Twitter) @anotherwalther
Pinned
Waltteri
@waltteri.net
· Dec 29
Hero Wavelength Spectral Sampling successfully implemented! 🎉
Both: 4 samples per pixel
Left: one wavelength per ray
Right: four wavelengths per ray
With only a modest increase in runtime duration, the image becomes much smoother. This is more efficient than just adding more samples per pixel!
Both: 4 samples per pixel
Left: one wavelength per ray
Right: four wavelengths per ray
With only a modest increase in runtime duration, the image becomes much smoother. This is more efficient than just adding more samples per pixel!
Reposted by Waltteri
One incident prevented by "not using" Rust (.unwrap). One incident (would've) been prevented "by" using Rust
✨ perfectly balanced ✨ as all things should be
✨ perfectly balanced ✨ as all things should be
"This is a straightforward error in the code, which had existed undetected for many years. This type of code error is prevented by languages with strong type systems. In our replacement for this code in our new FL2 proxy, which is written in Rust, the error did not occur."
Cloudflare outage on December 5, 2025
Cloudflare experienced a significant traffic outage on December 5, 2025, starting approximately at 8:47 UTC. The incident lasted approximately 25 minutes before resolution. We are sorry for the impac...
blog.cloudflare.com
December 6, 2025 at 6:27 PM
One incident prevented by "not using" Rust (.unwrap). One incident (would've) been prevented "by" using Rust
✨ perfectly balanced ✨ as all things should be
✨ perfectly balanced ✨ as all things should be
Reposted by Waltteri
Reposted by Waltteri
Reposted by Waltteri
the opening crawl for 2026 is gonna suck
IT IS A PERIOD OF TENSION AND INCREASING
UNREST. ALL NATIONS ARE HEADED
BY MANIACS. BILLIONAIRES STILL EXIST
FOR SOME REASON
IT IS A PERIOD OF TENSION AND INCREASING
UNREST. ALL NATIONS ARE HEADED
BY MANIACS. BILLIONAIRES STILL EXIST
FOR SOME REASON
December 5, 2025 at 8:24 PM
the opening crawl for 2026 is gonna suck
IT IS A PERIOD OF TENSION AND INCREASING
UNREST. ALL NATIONS ARE HEADED
BY MANIACS. BILLIONAIRES STILL EXIST
FOR SOME REASON
IT IS A PERIOD OF TENSION AND INCREASING
UNREST. ALL NATIONS ARE HEADED
BY MANIACS. BILLIONAIRES STILL EXIST
FOR SOME REASON
Reposted by Waltteri
Apropos of nothing: do we have any written experience reports of what it’s *like* as an engineer to be on call for various nines of availability?
I know the math for them, but I realised I don’t know if we have a collective idea of what it FEELS like to operate each of at those levels
Anyone? 👀
I know the math for them, but I realised I don’t know if we have a collective idea of what it FEELS like to operate each of at those levels
Anyone? 👀
December 5, 2025 at 9:36 AM
Apropos of nothing: do we have any written experience reports of what it’s *like* as an engineer to be on call for various nines of availability?
I know the math for them, but I realised I don’t know if we have a collective idea of what it FEELS like to operate each of at those levels
Anyone? 👀
I know the math for them, but I realised I don’t know if we have a collective idea of what it FEELS like to operate each of at those levels
Anyone? 👀
Reposted by Waltteri
hugops to, well, everyone I guess
December 5, 2025 at 9:18 AM
hugops to, well, everyone I guess
Reposted by Waltteri
Blindspots for Millennials 😅
IMO: it’s pretty accurate.
IMO: it’s pretty accurate.
December 5, 2025 at 12:12 AM
Blindspots for Millennials 😅
IMO: it’s pretty accurate.
IMO: it’s pretty accurate.
Reposted by Waltteri
good morning 🧡
December 4, 2025 at 6:23 AM
good morning 🧡
Reposted by Waltteri
First of many blog posts about the Rust vision doc process: blog.rust-lang.org/2025/12/03/l...
Lessons learned from the Rust Vision Doc process | Rust Blog
Empowering everyone to build reliable and efficient software.
blog.rust-lang.org
December 4, 2025 at 1:01 AM
First of many blog posts about the Rust vision doc process: blog.rust-lang.org/2025/12/03/l...
Reposted by Waltteri
Nothin else for it
October 20, 2025 at 4:02 PM
Nothin else for it
Reposted by Waltteri
A perfect CVSS 10 🧑🏻🍳💋
CVE-2025-55182: Unauthenticated remote code execution vulnerability in React Server Components
The vuln is in versions 19.0, 19.1.0, 19.1.1, and 19.2.0:
react-server-dom-webpack
react-server-dom-parcel
react-server-dom-turbopack
Upgrade immediately!
CVE-2025-55182: Unauthenticated remote code execution vulnerability in React Server Components
The vuln is in versions 19.0, 19.1.0, 19.1.1, and 19.2.0:
react-server-dom-webpack
react-server-dom-parcel
react-server-dom-turbopack
Upgrade immediately!
Critical Security Vulnerability in React Server Components – React
The library for web and native user interfaces
react.dev
December 3, 2025 at 4:23 PM
A perfect CVSS 10 🧑🏻🍳💋
CVE-2025-55182: Unauthenticated remote code execution vulnerability in React Server Components
The vuln is in versions 19.0, 19.1.0, 19.1.1, and 19.2.0:
react-server-dom-webpack
react-server-dom-parcel
react-server-dom-turbopack
Upgrade immediately!
CVE-2025-55182: Unauthenticated remote code execution vulnerability in React Server Components
The vuln is in versions 19.0, 19.1.0, 19.1.1, and 19.2.0:
react-server-dom-webpack
react-server-dom-parcel
react-server-dom-turbopack
Upgrade immediately!
Reposted by Waltteri
it's hard but I also feel that in many cases the solution lies in making the "accomodation" no longer an "accomodation" and just something available to everyone, or entirely obviated by the system
*especially* in education where most of these things are about bad proxies anyway
*especially* in education where most of these things are about bad proxies anyway
Balancing "no person with a disability should be denied accommodations" with "it's important to discourage non-disabled people from pretending to be disabled to take advantage of these accommodations" is really difficult and I don't have a great answer for what anyone should do about it.
December 3, 2025 at 5:02 PM
it's hard but I also feel that in many cases the solution lies in making the "accomodation" no longer an "accomodation" and just something available to everyone, or entirely obviated by the system
*especially* in education where most of these things are about bad proxies anyway
*especially* in education where most of these things are about bad proxies anyway
Reposted by Waltteri
users with similar passwords also liked:
December 2, 2025 at 9:18 PM
users with similar passwords also liked:
Reposted by Waltteri
what people think hacking is like: Mr. Robot
what hacking is actually like: Hmm. That’s weird
what hacking is actually like: Hmm. That’s weird
December 2, 2025 at 6:28 AM
what people think hacking is like: Mr. Robot
what hacking is actually like: Hmm. That’s weird
what hacking is actually like: Hmm. That’s weird
Reposted by Waltteri
a sign people really want a feature and find it good is when companies make turning it off a 12 part process (firefox), require registry modifications (microsoft) or contact support to reveal the real off switch instead of their two decoy toggles (google) so they can claim people don't turn it off 📈
firefox AI and slop disablers from tumblr for the people from local hero mckitterick. Tried it on my end and the browser is significantly faster now
(copy paste-able in the alt text)
(copy paste-able in the alt text)
December 2, 2025 at 10:20 AM
a sign people really want a feature and find it good is when companies make turning it off a 12 part process (firefox), require registry modifications (microsoft) or contact support to reveal the real off switch instead of their two decoy toggles (google) so they can claim people don't turn it off 📈
Reposted by Waltteri
"valve deserves 30% because they have a huge userbase that they use to give visibility to your game"
then why is my itch revenue that i pushed via my own social media accounts for november twice my steam net for the month
then why is my itch revenue that i pushed via my own social media accounts for november twice my steam net for the month
December 1, 2025 at 12:51 PM
"valve deserves 30% because they have a huge userbase that they use to give visibility to your game"
then why is my itch revenue that i pushed via my own social media accounts for november twice my steam net for the month
then why is my itch revenue that i pushed via my own social media accounts for november twice my steam net for the month
Reposted by Waltteri
Ever wonder why compilers use `xor eax, eax` to zero registers? It's smaller AND faster—CPUs optimise it out entirely!
Day 1 of Advent of Compiler Optimisations: xania.org/202512/01-xo...
Video: youtu.be/eLjZ48gqbyg
#AoCO2025
Day 1 of Advent of Compiler Optimisations: xania.org/202512/01-xo...
Video: youtu.be/eLjZ48gqbyg
#AoCO2025
Why xor eax, eax? — Matt Godbolt’s blog
Why do compilers love xor-ing registers so much?
xania.org
December 1, 2025 at 12:12 PM
Ever wonder why compilers use `xor eax, eax` to zero registers? It's smaller AND faster—CPUs optimise it out entirely!
Day 1 of Advent of Compiler Optimisations: xania.org/202512/01-xo...
Video: youtu.be/eLjZ48gqbyg
#AoCO2025
Day 1 of Advent of Compiler Optimisations: xania.org/202512/01-xo...
Video: youtu.be/eLjZ48gqbyg
#AoCO2025
Reposted by Waltteri
Last RustWeek, jyn guided ~15 stakeholders through ~2h of *intense* technical discussion until we emerged with a workable solution for cross-crate rustdoc JSON.
We've now made more progress in 6 months than in the prior 3 years.
This is just one of many such cases in jyn's portfolio.
We've now made more progress in 6 months than in the prior 3 years.
This is just one of many such cases in jyn's portfolio.
November 30, 2025 at 3:51 PM
Last RustWeek, jyn guided ~15 stakeholders through ~2h of *intense* technical discussion until we emerged with a workable solution for cross-crate rustdoc JSON.
We've now made more progress in 6 months than in the prior 3 years.
This is just one of many such cases in jyn's portfolio.
We've now made more progress in 6 months than in the prior 3 years.
This is just one of many such cases in jyn's portfolio.
Reposted by Waltteri
Finally tried uv. It’s not just fast: it’s laughably fast.
Like, “this is what should run every kind of package management on a whole computer” kind of fast.
Like, “this is what should run every kind of package management on a whole computer” kind of fast.
November 30, 2025 at 9:08 PM
Finally tried uv. It’s not just fast: it’s laughably fast.
Like, “this is what should run every kind of package management on a whole computer” kind of fast.
Like, “this is what should run every kind of package management on a whole computer” kind of fast.
Reposted by Waltteri
maybe we need a "thank the open source developer whose tools work flawlessly for you day"
November 29, 2025 at 9:43 PM
maybe we need a "thank the open source developer whose tools work flawlessly for you day"
Reposted by Waltteri
last week i remembered that macOS lets you set your own icons and that *I* have the power to delegitimize the professionalism of the software that runs on my machine, so here's a thread of the 16 new icons i've made so far
i really forgot how fun it was to just sit down and make art for myself :')
i really forgot how fun it was to just sit down and make art for myself :')
November 29, 2025 at 1:48 AM
last week i remembered that macOS lets you set your own icons and that *I* have the power to delegitimize the professionalism of the software that runs on my machine, so here's a thread of the 16 new icons i've made so far
i really forgot how fun it was to just sit down and make art for myself :')
i really forgot how fun it was to just sit down and make art for myself :')
at a techno club! music is a lovely thing 🧡
November 28, 2025 at 9:45 PM
at a techno club! music is a lovely thing 🧡
Reposted by Waltteri
ahah IT WORKS look it's a C² dual quaternion B-spline!!
this is interpolating *poses* in dual quaternion form, coupling position and rotation, instead of treating them independently (this is a really neat thing!!)
this is interpolating *poses* in dual quaternion form, coupling position and rotation, instead of treating them independently (this is a really neat thing!!)
November 26, 2025 at 3:10 AM
ahah IT WORKS look it's a C² dual quaternion B-spline!!
this is interpolating *poses* in dual quaternion form, coupling position and rotation, instead of treating them independently (this is a really neat thing!!)
this is interpolating *poses* in dual quaternion form, coupling position and rotation, instead of treating them independently (this is a really neat thing!!)