Felipe Astroza

⛅️

[Felipe Astroza @FelipeAstroza]

TIL: Never turn a lawn mower on its side to clean underneath. Motor oil can flow into the air filter and carburetor

[XGO Robot @luwu_dynamics]

Meet XGO-Duck —our latest bipedal desktop robot trained via Reinforcement Learning (RL)!
Through millions of trials in simulation, it has developed biological-like muscle memory. Even if it trips or gets pushed over, it automatically flaps its head and recovers seamlessly!

[Felipe Astroza @FelipeAstroza]

you know what could be ironically fun? Marc being the first human fully replaced by an AI chat bot, never say no to an interview, 24/7 omnipresent, no sick days, paid with NFTs

[David Crawshaw @davidcrawshaw]

While the industry is pouring resources into programs without GC (rust), I think the Jane Street OCaml folks have it figured out with OxCaml.

Almost all your code paths are cold and GC is net positive. 1% of your code is performance sensitive. Don't create GC pressure there.

[Emma Hilton @FondOfBeetles]

On Hantavirus: a (non-technical) thread.

Disclaimer: I am a biology PhD, but not virology/epidemiology. Husbandman is a virology PhD. But I’m told I’m good at communicating science, so here’s my take.

#Hantavirus

[Daniel San @dani_avila7]

So happy to see Paula from Chile 🇨🇱 win the Anthropic hackathon with Maieutic

Chile has serious talent, and we keep proving we can build great things with AI

[Aakash Gupta @aakashgupta]

Your brain has a circuit that doesn't know you live in a city. Its only job is to monitor whether birds are still singing. Right now, in this room, it is on.

The circuit predates primates. Mammals have been using ambient soundscape continuity as a predator-detection system for roughly 200 million years. Birds stop singing when something larger moves through their territory. For most of mammalian history, a forest full of song meant no large predator was nearby, and the cessation of sound was the warning. Your nervous system never updated this software.

The Max Planck Institute tested the inverse in 2022 with 295 participants. Six minutes of birdsong dropped anxiety with a medium effect size. Six minutes of traffic noise raised depression with the same. The effect worked on subjects who lived in dense urban environments and had no regular contact with nature. The brain still ran the check.

Birdsong sits in the 1,000 to 8,000 Hz range. Your brainstem reads continuous patterns in that band as a signal that nothing dangerous is currently moving through the environment. EEG data shows birdsong at 45 to 50 decibels boosts alpha wave activity by 14.1% relative to silence. Alpha is the brainwave signature of relaxed alertness. Push the same birdsong above 60 decibels and the response flips. Stress markers rise 29%. The circuit only trusts the signal at the volume of quiet conversation, which is exactly the volume birds sing at from a typical distance.

Three things happen simultaneously when the brain registers ambient safety. The amygdala downregulates. The parasympathetic nervous system takes over from the sympathetic. Heart rate variability rises, cortisol drops. The posterior cingulate cortex, which sits at the center of the rumination circuit, quiets down. King's College London tracked this through a smartphone study with over 1,200 participants and found the mood lift lasted hours after the sound stopped. People diagnosed with depression got the same response as healthy controls.

Most of what gets labeled mental fatigue is hypervigilance running in the background. Birdsong tells the circuit it can stand down, and the brain reallocates the freed compute everywhere else.

A quiet park feels different from a quiet office because the parks have sentinels.

[Bueno @0xBueno_]

If you know what this is, you had a real childhood

[Juan Carlos Muñoz Abogabir @JuanCaMunozA]

Les comparto mi carta al Director publicada hoy en La Tercera.

[Felipe Astroza @FelipeAstroza]

prediction: the only llm models that will survive are the open-weight. Why?
Trust: closed-weights models output quality can vary based on business (providers) needs. By contrast, open ones can be ran locally or in a cloud provider with some warranties and quality consistency

[Felipe Astroza @FelipeAstroza]

Consult doctor, not this guy

Sleeping is an active process, not a passive one, that is key to get your max potential in whatever you are working on

Feeling that sleep-deprived you is doing a wonderful job is in part because your brain is failing or partially getting shutdown

[Garry Tan @garrytan]

This is at once true but also unfathomable to me personally

I took modafinil just to stay awake longer to be able to turn the momentary crystalline structures I had in my brain into lines of code before sleep or human distraction turned it to grains of sand

I love coding but I love coding with AI even more. I speak it listens and we create. I see the structure and it is built.

There is no more powerful an experience to me than that.

[Felipe Astroza @FelipeAstroza]

I though it was just me

[Travis Akers 🇺🇸 @travisakers]

I believe Apple is gaslighting me with all these typos on my iPhone.

Either they’ve change iOS settings for the keyboard or I’m rapidly aging. But there’s no way my texting ability has declined this much.

[Felipe Astroza @FelipeAstroza]

Why stopping in a C compiler?

The definitive trust test: A Boeing 737 Max flight controller firmware in a flight that you board

[Felipe Astroza @FelipeAstroza]

if you are working in something new that lacks of multiple open source projects doing the same, it will be a disaster. Complex bugs will take all the gained time. Even so, it could be as exciting as starting to watch a movie in its halfway point. Many questions get you locked in

[Felipe Astroza @FelipeAstroza]

After experimenting a lot with agents to code I have some conclusions:
They are really good writing code patterns that were written by someone else in the past. So you don’t have to deal with known problems. This is good for productivity, it’s like using libraries but next level

[Felipe Astroza @FelipeAstroza]

After moving all the possible knobs I found the one that turned the pump on (Compressor Min Outdoor Temp)

The real issue here is I got NO feedback, warning, anything from ecobee UI/App, it just didn’t work, no reason given. Please @ecobee do better

[Felipe Astroza @FelipeAstroza]

Last night our master room didn’t get heated at all but the first floor did (fortunately). Turns out the first floor thermostat is basic enough to just do one thing: Meet the desired target temp.

[Felipe Astroza @FelipeAstroza]

Before finding this I took a look at everything else:
* Is a wiring issue? tester said it was OK
* Is a Heat pump problem? The good oldie was heating
* Is a O/B reversing valve misconfiguration? On cool / On heat didn’t change the outcome

[Polymarket @Polymarket]

BREAKING: GPUs to see massive price hikes this new year — RTX 5090 will cost $5,000 moving forward vs $2,000 previously.