AskHN Digest

1. Ask HN: How do I learn robotics in 2025?

Top comment by borjah

Do this course https://github.com/henki-robotics/robotics_essentials_ros2

Totally free, don't need to buy anything just a computer.

I've been designing electrical hardware for robots for the last 4 years for a big corporation and I can tell you, the fun and money is in the software but having another skill is awesome. Robotics is a place where multiple fields converge and if you find a good team they will help you to grow.

Embedded is the adjacent field after you complete the course. Maybe something like zephyr project.

If you want to get you feet wet with mechanical. Buy a A1 mini and play with onshape (www.onshape.com) to design your first pieces, supports for the motors or the board, try create you own gripper.

As for the electrical engineering, is the one with most pitfalls and the most expensive. A wrong voltage will release the magical smoke and is another 30$ for a board. Tread carefully. Start with the RP2040 or the RP2350, they are cheap and well documented. This skill will evolve hand by hand with the embedded coding. Start small. Learn about H-bridge and brushed motors before doing the jump to the bigboys and FOC control with brushless. Get a cheap soldering iron. If you can, a clone of the JBC C245 tips. Is the most versatile and you can find stuff in alie xpress for 45 or 50$ and would be similar to the tools you will find in the field without breaking the bank.

Search for ROS meetups. I could point you to some depending where in the world you are.

And above all, it will be a long journey. Don't dispear, do at your own time but don't forget the objective.

2. Ask HN: Startup getting spammed with PayPal disputes, what should we do?

Top comment by patio11

(I worked at a different processing company, which I am not speaking for.)

We're struggling to find the motive or intended outcome by the attacker(s).

The highest likelihood for me is that they're doing card/credential testing. They have either stolen or purchased a large number of stolen credentials. Those credentials are worth more individually if they are known to function. They can use any business on the Internet which sells anything and would tell someone "Sorry, can't sell you that because I couldn't charge your account/card/etc. Do you have another one?" to quickly winnow their set of credentials into a pile of ones which haven't been canceled yet and another pile. Another variation of this attack is their list is "literally just enumerate all the cards possible in a range and try to sift down to the cards that actually exist."

After sifting through to find the more valuable cards, they sell this onto another attacker at higher price of the mixed-working-and-not-working cards, or they pass it to their colleague who will attempt to hit the cards/creds for actual money.

Digital items are useful because people selling them have high margins and have lower defenses against fraud as a result. Cheap things, especially cheap things where they can pick their price, are useful because it is less likely to trigger the attention of the card holder or their bank. (This is one reason charities get abused very frequently, because they will often happily accept a $1 or lower donation, even one which is worth less than their lowest possible payment processing cost.) The bad guys don't want to be noticed because the real theft is in the future, by them or (more likely) by someone they sell this newly-more-valuable card information onto.

This hit the company I used to run back in the day, also on Paypal, and was quite frustrating. I solved it by adding a few heuristics to catch and giving a user matching those heuristics the product for free, with the usual message they got in case of a successful sale. This quickly spoils your website for the purpose they're trying to use it for, and the professional engineering team employed to abuse you experiences thirty seconds of confusion and regret before moving to the next site on their list. Back in the day, the bad guys were extremely bad at causing their browser instance to even try to look like a normal user in terms of e.g. pattern of data access prior to attempting to buy a thing.

Hope some of that is useful. Best of luck and skill. You can eventually pierce through to Paypal's attention here and they may have options available contingent on you being under card/credential testing attack, or they might not. I was not successful in doing so back in the day prior to solving the problem for myself.

Would also recommend building monitoring so you know this is happening in the future before the disputes roll in. Note that those disputes might be from them or from the legitimate users depending on exactly what credentials they have stolen, and in the case they are from legitimate users, you may not have caught all of the fraudulent charges yet. (Mentioning because you said "all of the charges" were disputed.) If I were you I'd try to cast a wider net and pre-emptively refund or review things in the wider net, both because the right thing to do and also because you may be able to head off more disputes later as e.g. people get their monthly statements.

3. Ask HN: Has anybody built search on top of Anna's Archive?

Top comment by bhaney

Honestly I don't think it would be that costly, but it would take a pretty long time to put together. I have a (few years old) copy of Library Genesis converted to plaintext and it's around 1TB. I think libgen proper was 50-100TB at the time, so we can probably assume that AA (~1PB) would be around 10-20TB when converted to plaintext. You'd probably spend several weeks torrenting a chunk of the archive, converting everything in it to plaintext, deleting the originals, then repeating with a new chunk until you have plaintext versions of everything in the archive. Then indexing all that for full text search would take even more storage and even more time, but still perfectly doable on commodity hardware.

The main barriers are going to be reliably extracting plaintext from the myriad of formats in the archive, cleaning up the data, and selecting a decent full text search database (god help you if you pick wrong and decide you want to switch and re-index everything later).

4. Ask HN: How do I learn practical electronic repair?

Top comment by atonse

Louis Rossmann’s electronics guide was the first time these concepts truly clicked for me: https://youtube.com/playlist?list=PLkVbIsAWN2ltOWmriIdOc5Cti...

Apart from that, just fix broken stuff. Practice like any other skill, like others have said.

Like decide what skills to learn based on what’s broken.

Need to solder something together? Buy the soldering iron. Need to figure out which capacitor you need to replace with? Learn how to identify capacitors and navigate digikey.com

5. Ask HN: How are parents who program teaching their kids today?

Top comment by Waterluvian

8 year old badly wants to be an engineer like his dad. :’) Public school got him into Scratch so he was animating things. The high school robotics team I mentor has Lego robotics kits for their community outreach program. Those kits use Scratch. So I got him a used kit and he spends an absolutely ridiculous amount of time making robots that do stuff.

This started at a very young age: we gave him access to a windows PC, not a tablet. So by 3 he could log in and get to YouTube kids. This meant that keyboard and mouse and web browser were very comfortable concepts.

We also gave him and his younger brother countless building toys. Meccano. Lego Technic.

A few lessons I’d love to empart:

- you can’t make your kid into this. His younger brother has no interest and is far more about sports. So we nurture that with him instead.

- open ended learning. I’m not sitting down and teaching him. All I do is make sure he has access to the tools, and I unstick him when he’s stuck.

- I connect concepts when I see them. “That’s called a loop. It’s just like that thing you did in Minecraft to make your machine work over and over again.”

- the learning must all be a side effect of having fun. Don’t try to teach programming. Do fun things and fill in the programming toolbox, tool by tool, as they’re needed.

- connect programming to what your kid is passionate about. Programming is a means to an end, not the end itself. My kid loves trains and has a Lego train set. I suggested he use his technic to automate the track switch. I then let him work at it for hours and hours over weeks, giving him breadcrumbs of what to consider next.

6. Ask HN: Options for One-Handed Typing

Top comment by lburton

This will depend a bit on the person but for me when I injured my right arm I found that my touch typing muscle memory worked surprisingly well with a toggle key to flip the left side of my keyboard to become a mirrored version of the right side. Each finger was still hitting the same key like it would if I was using my right hand to hit the key but on my left hand. This was fairly easy to accomplish on a QMK firmware keyboard (I was also already typing on a split keyboard so that might be part of the reason it was fairly easy to adjust). See https://docs.qmk.fm/features/swap_hands#swap-hands-action

7. Ask HN: What do you spend your money on?

Top comment by throwaway-money

I have spending habits that will probably make a good chunk of HN feel a little sick. I offer as a counterweight to all the frugality that inevitably accrues in these sorts of threads. Sorry, Financial Independence, Retire Early folks. Read at your own risk. Judge if you will.

Income is $450k / yr, engineer, 39 years old, no kids and no plans to have them. I have a chronic illness and retirement seems a distant and not very pleasant prospect. I like working and like to enjoy life.

* $5k / month on rent. (Nice apartment in a high cost of living city).

* At least $7k month goes into savings (I’m not totally financially irresponsible!)

* One pretty ordinary car, expect to drive it for 10 yrs, usual costs.

* $5k / month average on travel. My biggest luxury. I fly international business class sometimes but only when it’s “cheap”.

* $2k / month on groceries, wine, dining out. I enjoy fine dining.

* $3k / month on clothes and accessories. I’m a woman and I have a weakness for nice things, worst of all for designer bags. Yes I know it’s frivolous but the marginal utility is there for me.

* $1k / month on a personal trainer. Could I have the same level of fitness without it? In theory yes, in practice no.

The thing I wish I had more of is time, not in the sense of “retire and don’t work” but in the sense of “it would be nice to take a slight pay cut and work only 9 months of the year and travel more and spend the rest of the time reading, studying math again, and doing interesting projects.” Unfortunately that option isn’t really open to me, outside of consulting which I have no appetite for.

I didn’t get into engineering for the money, but out of love. I’d have done it anyway. But the money is nice, for sure. I save some and don’t feel the need to be unnecessarily frugal with the rest. I know I’m incredibly fortunate. Your mileage may vary, and especially if you have kids. Make your own choices according to your values.

8. Ask HN: Any good tools for viewing congressional bills?

Top comment by joshdata

Hi. I run GovTrack.

OP may have been unlucky on the timing. The site isn't usually down. Here's the link to the text of H.R. 1 on GovTrack: https://www.govtrack.us/congress/bills/119/hr1/text

We automatically add links to U.S. Code and other citations. In this case Congress.gov is missing rich formatting which we have (I'm not sure why they are missing it for this bill, normally they have it). GovTrack also allows making diff-like comparisons between bill versions and between bills (for example, you can see the last-minute changes made ahead of the vote on this bill).

Source code is available on GitHub if anyone wants to try making GovTrack better, although it's quite complicated because Congressional information is complicated and there's no real money behind this: https://github.com/govtrack/govtrack.us-web/

If anyone has particular thoughts on what would be helpful when viewing bill text --- within the realm of the information that is actually freely available --- I am all ears.

9. Ask HN: What's with the repeated job posts on "Who's hiring"?

Top comment by samcheng

I've posted on "Who's hiring" for years now, and hired many engineers from those posts. We reject the vast majority of candidates, and to those who we reject, it might seem like we can't hire "a single candidate." That's not true - if it were, I'd stop posting here!

10. Ask HN: Why are dating apps so bad? Why hasn't anyone made a good one?

Top comment by wryoak

The number one problem with dating apps is that they position themselves for self-selection and most people fail to select appropriate mates when given a whole shopping mall’s worth of candidates. I would never have swiped right on my current partner (7ish years). Or my first spouse, either. Two highly fulfilling relationships in my life that I never expected or tried to manifest initially.

People can generally identify when they have chemistry with someone, but not when they will have chemistry with someone, and most dating apps are run on the idea that you select whom you want to have chemistry with. Not whom you can or will, but want to have. All dating apps will converge to garbage because they focus on choice in love, rather than chance. They don’t throw you into a room with random people and let the real relationships blossom and the false ones fall away, they tell you to pick from a lineup of people whole you have never talked to (and to be honest probably will never talk to), but in real life we talk to random folks, sometimes that unattainable hottie and sometimes the perhaps homely but amiable passerby, and find out the brute force way which ones make us spark. It’s not about the subscription fees or the with dating apps, it’s about the fundamental disconnect between the freedom of election and the inability to act. The promise of consumption without the serendipity necessary to facilitate it.