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xcskier56

466 karma · joined October 2, 2015

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xcskier56··on Why are Soviet math textbooks so hardcore in comparison to US textbooks? (2017)
I had a Russian coach who described the Soviet training philosophy similarly.

(In a Russian accent) “if you throw many eggs at wall, most will break, but those that don’t are strong egg. Igor was strong egg”

He had multiple top 10s at world championships and 1 medal… definitely a strong egg

xcskier56··on The Mysterious Syndrome Destroying Endurance Athletes
I wonder if this is due to a lower rate of coaching. I don’t have a ton of first hand knowledge but most other endurance sports the athletes usually come up through well organized teams. Maybe the lack of organization (which is great for other reasons) leads to less coaching and therefore missing someone to tell you to rest and recover before you go over the edge.
xcskier56··on How version control will evolve for the agent boom
When your AI consumes documents that are out of date it introduce bugs and incorrect behavior into the system. Code is the only source of truth that actually matters.

The only artifacts outside of code that I don't explicitly end-date are user-story style requirements documents that I periodically revisit with the AI to make sure they're up to date.

One of the most annoying things I've seen AI do is accidentally pull in old requirements and start building off of them.

xcskier56··on Dynamic Workflows in Claude Code
Are these “features” just hooks to get people to burn more tokens faster?

I’m at the point where deciding what we should and should not do takes a lot more time than actually doing it. More agents just means running faster in potentially the wrong direction

xcskier56··on Outsourcing plus local AI will soon become more economical vs. frontier labs
There's always wtf, why did we add this feature, but at least in my experience, once a week or so I run into something in this category. Me: "AI, please cleanup/refactor/improve this thing" AI: "Roger that! I deleted the file so now it's perfectly clean" ... insert W.T.F.
xcskier56··on I Spent My Sabbatical Building a Power Meter for Sledgehammers
I could see this being used for fitness tests for cross country skiers. A very common exercise is med-ball slams. These aren’t a perfect analog to double poling but definitely close.

Being able to track your one rep max force you can generate could be an interesting metric especially for sprinters

xcskier56··on Spanish track was fractured before high-speed train disaster, report finds
Pure economics. In Minneapolis the railroad demanded a crash wall to separate the light rail trains from their trains. It runs 1 mile and somehow cost nearly $100 million. This is a 5x increase from the original estimate but still $20 million for a 1 mile wall is a heck of a lot of money
xcskier56··on The Palantir app helping ICE raids in Minneapolis
Here's an example. One of my friends works for a manufacturing company. He attended a protest. The next day ICE called his employer and he was informed that if he attended another protest he would be fired. All this b/c he had a small company logo on his jacket.

The ability to en-mass record, lookup and intimidate citizens is unprecedented and while I have no hard proof that this is due to Palantir, it sure smells like it

xcskier56··on AI is forcing us to write good code
SimpleCov in ruby has 2 metrics, line coverage and branch coverage. If you really want to be strict, get to 100% branch coverage. This really helps you flesh out all the various scenarios
xcskier56··on The battle to stop clever people betting
Seems like a great opportunity to curtail betting. You want to leach money out of people, well you have to leave yourself open to let the pros do it to you.
xcskier56··on A conspiracy to kill IE6 (2019)
My first startup we had to support IE 7 for a bit and then IE 8 until like 2017… I thought I had it bad then. I’m so glad I didn’t have to fight any older version
xcskier56··on The AI bubble is 17 times the size of the dot-com frenzy, analyst says
My friend owns a metal stamping company. One of the things they make are the heat dissipation fins for radiators. That portion of their business has grown 20x in the last few years.
xcskier56··on Death rates rose in hospital ERs after private equity firms took over
The entrenched interests would fight tooth and nail against this but I think that the drive towards simplifying billing and pricing is a generally good thing.

That being said, in my view, one of the fundamental problems with healthcare is that outside of truly elective procedures like cosmetic plastic surgery and lasik, it's nearly impossible to have free market economics function.

- There are HUGE information asymmetries between doctors and patients - Judging performance of doctors is very challenge. Reviews are terribly inaccurate, data can be better but has big problems, and even other doctors aren't good judges of doctors outside their specialty. - Right now at least, price discovery is nonexistent so you can't price shop and compete on price vs quality - Insurance means that consumers of healthcare are not actually footing the bill so they have no incentive to price shop. And most healthcare procedures are completely unaffordable so there's no way we can do without insurance - and finally it's really hard to make an economic decision that is literally life and death. Am I going to forgo a $100k surgery if it means I'll die? There's no choice there

All of these things lead me to the conclusion that healthcare is fundamentally incompatible with classic free market economics, and some form of single payer is the only solution to avoid us bankrupting our country spending on healthcare

xcskier56··on Hydra: Vehicles on the island – 'After the works they abandon them here'
One of my favorite things when I was here was seeing an Amazon Prime logo on the saddlebag of a donkey. That struck me as a very weird collision of old and new worlds
xcskier56··on Microservices are a tax your startup probably can't afford
I think that really depends on your definition. But I will also contend that even splitting your system into 2 or 3 services if it's not for strong reasons will 100% slow you down and cause long term headaches.

One project that I helped design had to split out a segment of the system b/c the data was eligibility records coming from health plans. This data had very different security and lifecycle requirements (e.g. we have to keep it for 7 or 10 years). Splitting out this service simplified some parts but any time we need to cross the boundary between the 2 services, the work takes probably twice as long as it would if it were in a single service. I don't think it was the wrong decision, but it the service definitely did not come for free

xcskier56··on Microservices are a tax your startup probably can't afford
Microservices make sense from a technical perspective in startups if:

- You need to use a different language than your core application. E.g. we build Rails apps but need to use R for a data pipeline and 100% could not build this in ruby.

- You have 1 service that has vastly different scaling requirements that the rest of your stack. Then splitting that part off into it's own service can help

- You have a portion of your data set that has vastly different security and lifecycle requirements. E.g. you're getting healthcare data from medicare.

Outside of those, and maybe a few other edge cases, I see basically no reason why a small startup should ever choose microservices... you're just setting yourself up for more work for little to no gain.

xcskier56··on RubyLLM: A delightful Ruby way to work with AI
From searching the codebase, I can only find eval() used in the markdown and the specs.

You’re totally right that eval()’ing unknown code is terrible but it doesn’t look like the gem itself is doing that.

The usage of eval() is in a user written tool in the docs. Definitely a bd example and should probably be changed

xcskier56··on Geothermal power is a climate moon shot beneath our feet
Iceland has boiling hot water at the surface and so doesn’t need to drill far to reach hot rocks do to all the volcanism there. This does not apply to the vast majority of the world
xcskier56··on Turn any bicycle electric
Am I missing something... it looks like the chainring is able to spin independently of the pedals, as if they moved the freewheel from the rear hub to the bottom bracket. Without that this would never work like he demonstrates. I've never seen the freewheel on the chainring/bottom bracket on a bike in the US, is this a common in other parts of the world?
xcskier56··on Optimizing Ruby's JSON, Part 1
We use a gem called olive branch. Yes it’s going to give you a performance hit, but it keeps you sane which is very worthwhile
xcskier56··on Starship Flight 5: Launch and booster catch [video]
But as far as I know, one Merlin engine produces more thrust than the empty booster weighs which means they have to time things perfectly to get to zero velocity exactly at the ground.

Super heavy can hover and even go down by throttling down more. This gives them more control for the landing and don’t have to time it exactly perfectly

xcskier56··on How long til we're all on Ozempic?
Traveling from a fairly walkable, but still car dependent midwestern city to NYC and also Europe in the last few months, it's amazing how much our living environment contributes. My first day in NYC and Europe I put in about 14k steps and at least according to my phone, one of those days I burned 750 cal just walking around to various places. Just by living my life I was WAY more active.

Making the good choice the easy/only choice is the only way to solve this problem long-term (without drugs)

xcskier56··on What's New in Ruby on Rails 8
I've been a rails dev for over a decade... love the framework and the language. About a year ago we started a client project where they had a fractional CTO that wanted to do the API & UI in typescript and so we settled on Nest.JS... tl;dr Nest is about as good of and opinionated of a framework as I've seen in Node land, but it definitely has it's edges:

- ORM: Like another commenter said, the ORM landscape in the node/typescript world is lacking. Every project feels like it's 70% complete and while you can find a project for each feature you want, you can't find one project with all of them. Ended up with TypeORM which has been very meh. - AuthZ: We went with casl which has a very similar feel to cancancan but lacks many of the important features for implementing more complex authz patterns like "you can edit this if you are in the group that owns this item" - Testing: Using Jest but the DSL and setup/teardown is way more complicated than rspec. - Flexibility. Patterns like single table inheritance and polymorphic relationships are poorly supported/fully lacking in typeorm and this bit us. - Learning curve: the DI system in Nest had a long learning curve, and having to sift through half a dozen or more options for each critical package (ORM, AuthN, AuthZ, etc) instead of having 1 or 2 clear choices made getting the project off the ground much much slower than anticipated. This can also just be chalked up to being green to the Node API landscape. - Adding to the learning curve, you have to be much more thoughtful about your code organization and architecture. We have an issue where we've introduced circular coupling through db-level repositories that is very hard to untangle. Rails gives you a great standard to work from that will take you a long ways

All in all it wasn't a terrible experience but the complexity of the domain lead to some challenges that we could have probably solve more elegantly and quickly in Rails. Even after a year of working the in project, I'd say my velocity for medium/simple tasks is still only 80% of what it is in Rails. Definitely lower when more complicated features are involved

xcskier56··on Why Appalachia flooded so from Helene's remnants
Reminds me of hurricane Irene in Vermont. They got less rain but some areas got 7" in a short timespan and b/c of the mountains and narrow valleys it decimated some towns. I went to help cleanup and in one place a tiny 50' wide river rose probably 20' and was over 1/4 mile wide covering the entire valley floor. It was really sobering to see the power and damage that can be caused so quickly. It also really illustrated how bad severe rain in mountainous terrain can be
xcskier56··on Cox slows Internet speeds in entire neighborhoods to punish any heavy users
I think US internet would give you a run for your money on best ISP in the country. Been doing gigabit symmetrical for probably close to 10 years at very reasonable prices. When I called customer support about having a static IP, just ended up talking shop with whoever was on the other side. Amazing
xcskier56··on How Olympic Timing Works
Yep! And a slight oddity is that at least the group I’ve worked with at Swiss timing is primarily Germans. I worked with them for XC Skiing events but I think they are also the ones who do track. There are multiple teams within Swiss timing that focus on different sports
xcskier56··on How Olympic Timing Works
This is why you’ll see the finish times in track move a little bit from the immediate unofficial time to the final time. A computer selects which frame was the finish and then someone on the timing crew will move the “line” a bit to exactly capture the correct time. This allows for instantaneous times and then correct final times
xcskier56··on Tour de France: How professional cycling teams eat and cook on the road
Through axels have become a very convenient excuse for bike changes. Watching Cavendish have his wheels changed in one of the early stages this year was so slow. It took a guy with a drill like a minute plus to do front and rear wheels.
xcskier56··on Tour de France: How professional cycling teams eat and cook on the road
It's a bit of both. If you're an athlete being tested at that level, you have to keep your country's antidoping agency informed of your whereabouts at all times. They will randomly send testers to wherever you are and you have a short time window, like 1-3 hours to show up. If you no-show 3 times (I think) it counts as a positive test and you're banned. I really don't know how someone could run in the trials with too many missed tests and not be allowed to race the olympics... I'm pretty sure the rules are the same.
xcskier56··on How I overcame my addiction to sugar
I'm not talking at the higher organism level, I'm talking at the very low-level chemistry in mitochondria. Glucose is "easier" to produce energy out of and so that happens preferentially from a chemistry perspective. Your body also needs a minimum level of glucose to survive.

When there isn't enough glycogen, the chemical balances in the mitochondria change and the liver mitochondria will produce glucose from whatever they have. This isn't a "decision" just the relative amounts of the chemicals change leading to one chemical pathway becoming more likely compared to another. This is all mediated by the random collisions of molecules in your cells. If you have a lot less of one molecule compared to another, the frequency that molecules find each other to do one thing v/s the other will change leading to different chemical pathways becoming more or less active.

There are many routes for your body to produce glucose. It is "easier" for your body to produce it from gluconegenic amino acids (not all amino acids can be used to produce glucose) than it is from fatty acids. It's the process of converting fatty acids into glucose that generates ketones. So when you have excess amino acids that can be turned into glucose, the chemistry will prefer this pathway over breaking down fat into glucose and this will lead to lower ketone production overall and kick you out of ketosis.

(I think I've gotten the gist of this right but any biochem experts feel free to correct me)

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