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flaviut

599 karma · joined January 9, 2021

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flaviut··on I built Excel for Uber and they ditched it
> Because no programmer is going to sign that.

I have. I got an extra $130k out of it.

It's a work of art. Even this comment is a violation of the agreement, since I don't own the copyright to anything I do apparently, either in or out of the scope of my employment, so therefore I can't give Y Combinator a license to display this comment.

I even talked to the company's legal team about the absurdity of the agreement & they were unwilling to budge.

The relevant portion of the agreement, for your reading amusement: https://pastebin.com/ZF9MEkfG

flaviut··on Carrefour puts ‘shrinkflation’ price warnings on food to shame brands
I've made a userscript for this! https://greasyfork.org/en/scripts/429539-unit-prices-on-krog...

Kroger doesn't publish unit prices on their websites, but they do publish quantities. They'll sometimes mix the units up (L, floz, see mapUnit() https://greasyfork.org/en/scripts/429539-unit-prices-on-krog...), but generally they're OK.

The script will normalize everything to a specific metric unit & present a unit price on the page.

Why stores have this horrible setup? Probably weaponized incompetence. Would be nice to have the FTC step in with some regulation.

flaviut··on Arduino raises $22M Series B round
Installing toolchains on Windows is a huge pain, and installing the a consistent version of toolchains across platforms is also hard.

Platformio is a package manager for embedded systems

flaviut··on OpenTelemetry in 2023
I hope I'm not coming across as negative! Y'all are just have a much younger product, and have not had time to do all the polish and tiny tweaks. I'm also much more familiar with Datadog, and sometimes a learning curve feels like missing features.

- I really like your new Logs & Traces Explorers. I spend a lot of time coming up with queries, and having a focused place for that is great. Especially since there's now a way to quickly turn my query into an alert or a dashboard item.

- You've also recently (6mo?) improved the autocomplete dramatically! This is awesome, and one of my annoyances with Datadog

Other feedback, and honestly this is all very minor. I'd be perfectly happy if nothing ever changed.

- where do I go see the metrics? There's no "Metrics" tab the way there's a "Logs" and "Traces" tab. A "Metrics Explorer" would be great.

- when I add a new plot, having to start out with a blank slate is not great. Datadog defaults to a generic system.cpu query just to fill something in, I find this helpful.

- when I have a plot in a dashboard and I see it is trending in the wrong direction, it would be nice to be able to create an alert directly from the chart rather than have to copy the query over.

- the exceptions tab is very helpful, but I've only recently discovered the LOW_CARDINAL_EXCEPTION_GROUPING flag. It'd be super nice if the variable part of exceptions was automatically detected and they were grouped

- once nice thing in DD is being able to preview a span from a log or logs from a span without opening a new page. Or previewing a span from the global page. Temporary popping this stuff up in a sidebar would be great.

- I'm not sure if there's a way to view only root spans in the trace viewer.

- This might be a problem with the spring boot instrumentation, but I can't see how to figure out what kind of span it is. Is it a `http.request`, `db.query`, etc?

flaviut··on OpenTelemetry in 2023
I've got a small personal project submitting traces/logs/metrics to Clickhouse via SigNoz. Only about 400k-800k spans per day (https://i.imgur.com/s0J6Mzo.png), but running on a single t4g.small with CPU typically at 11% and IOPS at 4%. I also have everything older than a certain number of GB getting pushed to a sc1 cold storage drive.

w/ 1 month retention for traces:

    ┌─parts.table─────────────────┬──────rows─┬─disk_size──┬─engine────┬─compressed_size─┬─uncompressed_size─┬────ratio─┐
    │ signoz_index_v2             │  26902115 │ 17.06 GiB  │ MergeTree │ 6.21 GiB        │ 66.74 GiB         │   0.0930 │
    │ durationSort                │  26901998 │ 5.44 GiB   │ MergeTree │ 5.40 GiB        │ 53.02 GiB         │  0.10190 │
    │ trace_log                   │ 123185362 │ 2.64 GiB   │ MergeTree │ 2.64 GiB        │ 37.96 GiB         │   0.0695 │
    │ trace_log_0                 │ 120052084 │ 2.46 GiB   │ MergeTree │ 2.45 GiB        │ 37.60 GiB         │  0.06528 │
    │ signoz_spans                │  26902115 │ 2.21 GiB   │ MergeTree │ 2.21 GiB        │ 76.73 GiB         │ 0.028784 │
    │ query_log                   │  16384865 │ 1.91 GiB   │ MergeTree │ 1.90 GiB        │ 18.31 GiB         │  0.10398 │
    │ part_log                    │  17906105 │ 846.73 MiB │ MergeTree │ 845.39 MiB      │ 3.84 GiB          │  0.21521 │
    │ metric_log                  │   4713151 │ 820.92 MiB │ MergeTree │ 806.13 MiB      │ 14.56 GiB         │  0.05405 │
    │ part_log_0                  │  15632289 │ 702.82 MiB │ MergeTree │ 701.70 MiB      │ 3.34 GiB          │  0.20490 │
    │ asynchronous_metric_log     │ 795170674 │ 576.24 MiB │ MergeTree │ 562.50 MiB      │ 11.11 GiB         │ 0.049429 │
    │ query_views_log             │   6597156 │ 461.35 MiB │ MergeTree │ 459.75 MiB      │ 6.36 GiB          │  0.07060 │
    │ logs                        │   6448259 │ 408.59 MiB │ MergeTree │ 406.65 MiB      │ 5.99 GiB          │  0.06627 │
    │ samples_v2                  │ 949110122 │ 345.01 MiB │ MergeTree │ 325.31 MiB      │ 22.09 GiB         │ 0.014382 │
If I was less stupid I'd get a machine with the recommended Clickhouse specs and save myself a few hours of tuning, but this works great.

Downsides:

- clickhouse takes about 5 minute to start up because my tiny sc1 drive has like 4 IOPS allowed

- signoz's UI isn't amazing. It's totally functional, and they've been improving very quickly, but don't expect datadog-level polish

flaviut··on Experian fined $650K by the FTC and DOJ for spam emails with no opt out
I believe you can express your displeasure with this settlement at Civil.Feedback@usdoj.gov, as well as to your elected congresspeople: https://www.congress.gov/members/find-your-member
flaviut··on Critical hearing looms in battle over California’s last nuclear power plant
No. Coal plants on the other hand: https://www.scientificamerican.com/article/coal-ash-is-more-...

> The chances of experiencing adverse health effects from radiation are slim for both nuclear and coal-fired power plants—they're just somewhat higher for the coal ones. "You're talking about one chance in a billion for nuclear power plants," Christensen says. "And it's one in 10 million to one in a hundred million for coal plants."

flaviut··on Institutionalized Belief in the Greater Fool
Executive VP at a bank is just a standard rank-and-file role. It is not a leadership position.
flaviut··on The process of making fake food [video]
I think the colored wax buckets were sitting in a tray full of warm water. Maybe even with the small warming burners underneath like how catering folks do it.
flaviut··on An open-source, free circuit simulator
Wokwi is a completely different tool. You would never be able to use it for radio frequency simulation, or much outside of "virtual breadboard" (although I've tried!)

Its strengths are around simulating microcontrollers.

flaviut··on Digikey's Physical Connectors Tutorial
Low volume, and everyone who isn't a big company just buys clones.

If you are a company or care about reliability, you have to get the OEM version but hopeful you amortize it over thousands of crimps.

flaviut··on The pull request hack is fucking magic
Javascript in the SVGs?
flaviut··on NRF52840 Connect Kit – Rapid prototyping kit for your next connected projects
None of Espressif's products are able to compete with the nrf52 on low-power & battery-powered applications.

Wifi in particularly is a huge power hog and isn't really usable in low-power situations.

flaviut··on Sacrifice the first 13 years of your life to Google for 2M
You can buy a small fraction of a chicken farm, so that when chicken prices go up, so does the value of the chicken farm.

Then you simply sell a tiny fraction of your chicken farm, and use that money to buy a chicken.

That way you can preserve your chicken buying power through the years, rather than having a guaranteed -2% return on your money.

flaviut··on Charles Schwab facing internal meltdown after C-level abruptly reverses on RTO
I'm a Schwab customer & I've reached out to them to file a complaint about this new policy.

I've been really happy with my experience there and I feel like I owe it to the folks who actually made that happen.

If you're lazy, here's the text of my complaint:

> Hey, I've heard about Schwab's new return-to-office policy. I'm also not happy about management's betrayal of the folks who have helped me out tons over the years, and I'll be moving my money elsewhere if this policy does not change.

flaviut··on OnBoard – A New Grants Program to Fund $100 in PCB Costs for Teenagers
I haven't used EasyEDA, but I've seen many schematics built in EasyEDA and I'm not impressed.

Rather than having a carefully hand-built symbols library, EasyEDA seems to have just autogenerated symbols, where the pins are all in order from 1 to n. This is not good for schematic readability & fails to teach folks good schematic layout conventions.

Poor schematic quality could be because EasyEDA is mostly used by noobs, but I think it's worth it for even noobs to use KiCad. It's not too hard to export the files JLCPCB needs.

flaviut··on WHO advises against use of artificial sweeteners
That's not vaping nicotine.

These kids are vaping THC adulterated with vitamin E[1]. Vitamin E is added because it makes a cut product thicker, and thickness is thought of as an indicator of quality. My guess here is that marijuana still has a stigma/is illegal, so these kids are finding it easier to just blame nicotine vapes to try and get themselves out of trouble.

There's no reason to cut nicotine vape liquid since the base ingredients (vegetable glycerin + propylene glycol) are absurdly cheap.

[1]: https://www.cdc.gov/tobacco/basic_information/e-cigarettes/s...

flaviut··on Donut: OCR-Free Document Understanding Transformer
I was just processing a document with tesseract & ocrmypdf, and two things:

My first time processing it, I used `ocrmypdf --redo-ocr` because it looked like there was some existing OCR. After processing, the OCR was crap because ocrmypdf didn't realize it was OCR but thought it was real text in the document that should be kept. This was fixable using `ocrmypdf --force-ocr`.

Before realizing this, I discovered that Tesseract 4 & 5 use a neural network-based recognition. I then came across this step-by-step guide on fine-tuning Tesseract for a specific document set: https://www.statworx.com/en/content-hub/blog/fine-tuning-tes...

I didn't end up following the fine-tuning process because at this point `ocrmypdf --force-ocr` worked excellently, but I thought the draw_box_file_data.py script from their example was particularly useful: https://gist.github.com/flaviut/d901be509425098645e4ae527a9e...

flaviut··on Server-sent events
I've never worked with Web Workers, but the doc page mentions them at the very top. Isn't that the intended workaround? Have a background thread that receives the events & coordinates, rather than having each page deal with them?
flaviut··on CI/CD with KiCad and Gitlab
spicyjpeg basically described the sort of thing I was thinking of, but even for more boring things like opamps or transistors, it's a big hassle to track down or design a simulation model.

There's a semi-standardized file format for simulation models, but there are still differences between simulators. And every manufacturer's website is a different kind of poorly-organized, so it's hard to even find the models.

The other thing is things where high frequencies exist, like switching regulators. It's possible to simulate them, but there's all sorts of parasitics (imperfections from the circuit being made out of real stuff rather than lines on paper) that impact the circuit. I've only used KiCad, so I don't know if the commercial software here can model these parasitics, but they can have a big on performance.

flaviut··on CI/CD with KiCad and Gitlab
> Is it hardware testing at the simulation/emulation level as a "digital twin"

This, very likely.

It's possible to set up simulations of certain sections of the hardware using some Spice software, but it's quite time consuming and I'm not sure if anyone's built a way to compare the output of the simulation to expected output.

Simulating any entire circuit as a whole is impossible, since lots of parts just cannot be simulated.

flaviut··on My alpha Pico-based CH32V003 debug tool is ready for a few testers
Very cool! For now, I'm using the PY32F002A for my low-cost MCU needs, but if this project was around a few months ago, I would have had to think harder about it.

I like that you've included a GDB server directly in the project, I've had way too much trouble getting a version of openocd that works properly for my pico projects, and now that's just cut out of the picture :)

flaviut··on A novel ultramicro supercapacitor with ultrahigh charge storage capability
https://i.imgur.com/xdiQTLT.png

Like this? It's difficult to take a picture of an one atom thick material. You can also easily produce it at home if you'd like.

Or if you'd like to produce larger quantities, it seems like that's also doable at home with just a few hundred dollars of equipment: https://www.youtube.com/watch?v=3hHoL77QDkg

flaviut··on Google Mars (2005)
Check this newer version: https://www.google.com/maps/space/mars/@17.5325978,179.82741...

They also have many other planets and celestial bodies here.

flaviut··on Everything advertised on social media is overpriced junk
I don't see that being a problem--they sold junk, and rightfully their profits will decrease because that junk was returned.

They wouldn't have this problem if they sold quality products.

flaviut··on Circuit.js – Electronic circuit simulator on the web
Library curation is a massive amount of work. Pretty much the reason I end up using falstad instead of a SPICE is because I end up spending all day tracking down and debugging issues with simulation models.
flaviut··on ‘America does so much more to subsidise affluence than alleviate poverty’
I believe they're referring specifically to the Economic Impact Payments, since those had zero controls from most peoples' perspective. Money just showed up in your bank account.
flaviut··on PC keyboard hides an interesting secret
No, definitely not. You can either use the SSD's built-in firmware encryption, which is always on anyways (to allow for fast erase), or you can configure your system to send TRIM commands.
flaviut··on Experian is a pile of dark pattern garbage
I filed a complaint with the CFPB about exactly this last year: https://www.consumerfinance.gov/data-research/consumer-compl...

Their response was:

1. a notice that they needed more time to handle my complaint, and then on the deadline to respond 2. 650 words that can be summarized as a) "Experian Consumer Services" is not the same as Experian, the credit reporting agency b) The terms of service allow Experian Consumer Services to do what they want c) You are already unsubscribed from emails from our partners

Regardless, I'd suggest everyone else affected by this issue file a complaint as well. At the very least, these complaints are not cheap to process.

flaviut··on Did an F-22 Blow Up an Illinois Club’s Hobby Balloon?
There are folks from all around the world online, and many countries place their currency symbol after the amount.
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