Hacker News: haruka_ff

New comment by haruka_ff in "Show HN: Gemini Pro 3 imagines the HN front page 10 years from now"

haruka_ff — Thu, 11 Dec 2025 14:54:34 +0000

I wasn't expecting to see the reference here ::D

New comment by haruka_ff in "I invited strangers to message me through a receipt printer"

haruka_ff — Sat, 25 Oct 2025 09:12:15 +0000

I have a Star Micronics receipt printer and have a similar setup, and when people in my community used it, it was fun.

And the issue is that, it's only fun as long as you have people using it...

I did write a StarPRNT protocol library for it, but in hindsight, I probably should have used ESC/POS instead.

New comment by haruka_ff in "Kurt Got Got"

haruka_ff — Thu, 09 Oct 2025 05:10:35 +0000

MetaMask (the crypto wallet) has one that shows warning pages to all domains that are remotely similar to crypto-related domains, and it is very prone to false positives and annoying. They have to maintain a list to skip the detection for real domains, and it's really inefficient.

Feels like this kind of detection is hard to balance, and calling legit websites possible phishing might be problematic...

New comment by haruka_ff in "A real-time 3D digital map of Tokyo's public transport system"

haruka_ff — Tue, 10 Oct 2023 22:11:37 +0000

I wonder how the map handled the accuracy issue of the timetable data: the public timetables are only accurate to the minutes, but the trains on the map are not only arriving / departing at 0 second. I believe accurate timetables that are accurate to 5 seconds (actual accuracy) are not published anywhere. I'm now very curious how accurate the trains on the map are, as there might be up to 55 seconds of error.

I don't have too many opportunities to take the trains nowadays, and when I had to take the trains I always forget to check this.

New comment by haruka_ff in "Illegal Life Pro Tip: Want to ruin your competitor's business?"

haruka_ff — Tue, 04 Jul 2023 10:55:57 +0000

> Is it really so hard for people to separate good from bad?

If you mean "HN people", then probably no; but if you mean more generalized "people", then definitely yes. Unfortunately, your customers are much more likely from the latter group.

Also, being in a sad state doesn't really mean it "has no use case", right?

New comment by haruka_ff in "Show HN: I made a SQL game to help people learn / challenge their skills"

haruka_ff — Sat, 22 Apr 2023 19:45:19 +0000

More than halfway through the story mode, and there are some really annoying issues around and I can't find a way to provide feedback, so I'll leave them here:

1. There should be a way to inspect the schema. As one commenter mentioned, `show create table` doesn't work, and you'll have to `select *` which will count as incorrect answer, making the error counter almost meaningless. I know there are hints and most of the times they works, but there are situations that you would want to directly look at column names (see below).

2. You can't edit the previous steps in multi-step chapters, and the answer checker is not catching some errors. For example, the step 1 of chapter 19 has the hint "watch out for column ordering", but because of point 1, there is no way to know the table structure beforehand, and I decided to just do it blindly without adjusting the order to see how it goes. The answer is obviously incorrect, but the game accepted it as the correct answer and made the textarea readonly. Now I can't fix that and have to fix it again after all the steps are completed, but some intermediate steps will be using the wrong answer.

3. (slight spoiler?) There is a logic error in step 5 of chapter 19: considering the lifts are denoted by unique names (as you are asked to group by it), the answer checker expected lifts with inoperable malfunctions to be "usable", while the hint indicates otherwise.

4. The TV effect consumes a lot of CPU power, at least on Firefox (didn't test on other browsers).

Still a great one overall, looking forward to try the challenge mode after I finish the story.

New comment by haruka_ff in "Gmail accepts forged YouTube emails"

haruka_ff — Thu, 02 Jun 2022 08:42:57 +0000

This actually sounds like the most plausible reason considering there is really no other incentive to do this.

New comment by haruka_ff in "Yet another macOS privacy protections bypass"

haruka_ff — Tue, 01 Dec 2020 20:27:00 +0000

BTW, this is also how iOS apps could detect jailbreak status of the device: just try to open paths like `/var/lib/apt`, if it does not exist, it should return ENOENT; otherwise you would know this device is “not clean”.

Didn’t think the sandboxing on macOS also has this issue.