derethanhausen (u/derethanhausen)

derethanhausen commented on Advent of Code 2024 adventofcode.com/2024/abo... · Posted by u/thinkingemote

sebtron · a year ago

Your restrictions sound quite challenging, good luck!

Last year I solved all the problems in C without external libraries [1] and I enjoyed it a lot. It forced me implement some low-level stuff that I had forgotten how to do (e.g. a heap) and to write some numerical routines myself (easier than you'd think!).

[1] https://github.com/sebastianotronto/aoc/tree/master/2023

derethanhausen · a year ago

Fitting, given that iirc one of the problems was to implement a hashtable!

derethanhausen commented on Ask HN: Who wants to be hired? (April 2024) · Posted by u/whoishiring

derethanhausen · 2 years ago

Location: Utah, USA

Remote: Preferred

Willing to relocate: Depends on role

Technologies: JavaScript, React, Ruby, Go, JavaScript, C/C++, Rust, K8s, AWS, Linux, HTML, CSS, Git, Docker, DevOps, Extreme Programming, Site Reliability Engineering, Cloud Optimization,

Résumé/CV: Available upon request

Email: ethanransom246 [at] gmail

GitHub: https://github.com/ethransom/

LinkedIn: https://www.linkedin.com/in/ethan-ran/

Senior Software Engineer with 5+ years professional experience. Demonstrated history of shipping on a team. I have nearly 10 years of experience working on web technologies, most recently with Ruby, Elixir, and React, but I also have a significant systems background (SQL internals, Linux, Distributed Systems, Concurrency Fundamentals). Passionate about high performance, high efficiency software and can sling code with the best of them.

derethanhausen commented on Mexico's heirloom corn strains are resurging amid more demand nbcnews.com/news/latino/h... · Posted by u/DocFeind

zwieback · 2 years ago

Has anyone grown heirloom varieties in their home garden and is it worthwhile, e.g. does it taste good or is it more for the nostalgia factor?

derethanhausen · 2 years ago

I think there’s also a variety factor, heirlooms are usually very unique and fun-looking. But yes I think taste is generally good too. I’m growing heirloom Zucchini and Tomatoes this year. The tomato flavor certainly isn’t bad, about on par with other good garden tomatoes. The zucchini on the other hand is out of this world good, and retains the flavor even when the fruits are large, unusual for most other Zuccs. (Variety is Costata Romanesco)

derethanhausen commented on The computer graphics industry got started at the university of Utah spectrum.ieee.org/history... · Posted by u/sohkamyung

derethanhausen · 3 years ago

Let’s go Utes!

derethanhausen commented on CATL has announced a new “condensed” battery with 500 Wh/kg thedriven.io/2023/04/21/w... · Posted by u/rippercushions

leoedin · 3 years ago

The big reason for this is thermodynamics. A conventional internal combustion engine car has to convert chemical energy to kinetic energy - the absolute best theoretical efficiency of this might be 70%, but in practice it's more like 30%. Electric cars have to pay the same thermodynamic penalty, but they pay it at the power station (In practice, thanks to renewables, not all the electricity used to charge a car will come from hydrocarbons - but let's assume it does for ease of comparison sakes). It's much easier to build highly efficient hydrocarbon power stations - typical efficiencies range from 40-60%.

So when you look at the headline "efficiency" of an electric car, you need to take that thermodynamic penalty into account first.

A modern series hybrid like a Toyota Prius is effectively an electric vehicle and a gas generator (which means it has the same efficiency gains due to regenerative braking). That gets 52 mpg, which is about 493 Wh/km. If you generated the 225 Wh the Tesla needs in even the most efficient combined cycle gas turbine powerplant you'd need 375 Wh. Less - but not nearly as drastic as it first seems.

Renewables change the picture though - once you have significant renewable generation the carbon intensity of electricity starts dropping, which means that remote powerplant vs local powerplant argument falls apart. That is when the real power of electric vehicles kicks in - they can take their energy from anywhere.

derethanhausen · 3 years ago

The Prius' efficiency comes from much much more than regenerative braking. Part is a focus on good aero and low weight, like many electric cars. But most is from leveraging the electric motors to allow the engine to run at max thermal efficiency (probably a touch above your 30% figure) at nearly all times.

ICEs are most efficient under medium-low RPMs and high load. The electric motors can sustain low speed cruising, letting the engine shut off entirely if it wouldn't be well utilized, and also fill in for high torque demand to keep engine power output lower.

derethanhausen commented on Heat dome causing record breaking heat wave severe-weather.eu/global-... · Posted by u/goesup12

rad_gruchalski · 4 years ago

Let’s not forget about big rocks falling from the sky, volcanoes and the Sun killing this planet inevitably in about 1b years from now. There better be a planet B at some point.

derethanhausen · 4 years ago

Even an Earth ravaged by big rocks and volcanoes would be much more survivable than Mars in its current state.

derethanhausen commented on Do you really need Redis? How to get away with just PostgreSQL spin.atomicobject.com/202... · Posted by u/hyzyla

nickjj · 5 years ago

I think one of the biggest advantages of using Redis for job queing vs Postgres comes down to library support.

For example Python has Celery and Ruby has Sidekiq. As far as I know there's no libraries in either language that has something as battle hardened with comparable features for background tasks using Postgres as a backend.

There's a big difference between getting something to work in a demo (achievable by skimming PG's docs and rolling your own job queue) vs using something that has tens of thousands of hours of dev time and tons of real world usage.

I'm all for using PG for things like full text search when I can because it drastically reduces operation complexity if you can avoid needing to run Elasticsearch, but Redis on the other hand is a swiss army knife of awesome. It's often used for caching or as a session back-end so you probably have it as part of your stack already. It's also really easy to run, uses almost no resources and is in the same tier as nginx in terms of how crazy efficient it is and how reliable it is. I don't see not using Redis for a job queue as that big of a win.

derethanhausen · 5 years ago

The elixir world has Oban[0] which implements quite a lot of advanced job features on top of PG. Admittedly it doesn’t quite have the usage of Celery and Sidekiq but most queueing libraries don’t.

[0] https://github.com/sorentwo/oban