Polymath Engineer Weekly #76
Polymath Engineer Weekly #76
Monte Carlo, Engineering Managers, Hexagon Grids, RFCs, Melatonin, UUIDs and Beating the markets
Hello again. Another week, more awesome links =)
Links of the week
Whatever your views on the relevance in 2023 of the Agile Manifesto, no practitioner should ignore the very first line of “uncovering better ways”. I’ve always tried to hold myself and peers I work with true to that statement, with one of my biggest learning/unlearning moments being around velocity and story points. Instead of these approaches, moving towards techniques such as probabilistic forecasting and Monte Carlo simulation is more aligned to modern, more complex environments.
Questionable Advice: “My boss says we don’t need any engineering managers. Is he right?“
You’ve probably heard this canard: “Engineers do the technical work, managers do the people work.” I hate it. ☺️ I think it misconstrues the fundamental nature of sociotechnical systems. The “socio” and “technical” of sociotechnical systems are not neatly separable, they are interwoven and interdependent. There is actually precious little that is purely technical work or purely people work; there is a metric shitload of glue work that draws upon both skill sets.
How Uber Finds Nearby Drivers at 1 Million Requests per Second
They created a global grid on H3 with 122 base cells. Yet 12 out of 122 base cells are pentagons because it’s not possible to tile a sphere (Earth) only with hexagons. H3 treats the pentagon as a hexagon without a part.
Besides hexagons don’t subdivide perfectly. So they subdivide a hexagon into 7 hexagons with a known amount of error. And the child hexagons get rotated to fit the shape of the parent hexagon.
The superpower of an RFC process is as a forcing function to have the writer themselves really think through the scope of the change they’re proposing. There’s a bad tendency in a lot of people to have an idea, not think about it in too much depth, start implementation, and only then discover a colorful assortment of complications, necessitating patch after patch to follow up the original change, and unless there’s a more senior person to insist on quality control, more often than not hack after hack as the deadline draws nearer.
Melatonin: Much More Than You Wanted To Know
Based on a bunch of studies that either favor the lower dose or show no difference between doses, plus clear evidence that 0.3 mg produces an effect closest to natural melatonin spikes in healthy people, plus UpToDate usually having the best recommendations, I’m in favor of the 0.3 mg number. I think you could make an argument for anything up to 1 mg. Anything beyond that and you’re definitely too high. Excess melatonin isn’t grossly dangerous, but tends to produce tolerance and might mess up your chronobiology in other ways.
How to Do UUID as Primary Keys the Right Way
Any properly designed relational database table owns a Primary Key (PK) allowing you to uniquely and stably identify each record. Even if the primary key can be composite (built of several columns), it is a widespread good practice to dedicate a special column (often named id or id_<table name>) to this end. This special column is used to technically identify records and can be used as foreign keys in relations.
Book of the Week
A Man for All Markets: From Las Vegas to Wall Street, How I Beat the Dealer and the Market
Do you have any more links our community should read? Feel free to post them on the comments.
Have a nice week. 😉
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