btrettel

Joined 9 years ago

Karma
4,210
Submissions
1,246
Member since
Oct 6
I am a mechanical engineer working in computational fluid dynamics.

Personal website (including contact information): http://trettel.us/

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Recent submissions

Comment · 1 day ago
It might be worth putting "(2013)" in the title. At first, I thought the title was clickbait about using LLMs without thinking, but it's from well before LLMs and makes an interesting point. I wouldn't say that "Stop Thinking" is the right way to phrase the author's point, though, but it does get attention.
Comment · 8 days ago
I'm the administrator of 3 online forums, 2 of which are basically archives at this point. All 3 forums were getting absolutely hammered by bots. In fact, all 3 were taken offline by their hosts due to the heavy traffic in 2026. I installed Anubis on 2 of them and bot traffic decreased dramatically to the point where it appears to be only legitimate bots. (Unfortunately, the other forum couldn't use Anubis so easily and has remained offline since then.)

It's clear to me that Anubis won't work forever. You don't need to get as sophisticated as this blog post either as you can bypass the proof-of-work challenge with the right user agent string. I think the reason I'm not seeing bots change their behavior in response to me adding Anubis is simply that my forums are relatively small players. To the people running these scraper bots, a handful of forums adding Anubis is no big deal to them as there are tons of other sites they can scrape.

I think turning the forums that are archives into static HTML is the best path forward for those forums, but that's easier said than done. I've also been thinking about writing a new forum software where all of the content pages are static HTML, and the only dynamic pages are where dynamic features are unavoidable like when posting.

Comment · 9 days ago
I visited yesterday according to my browser history. I contributed last probably over a year ago, but I don't know off the top of my head.
Comment · 9 days ago
The Library of Congress did in fact switch their catalog to a new system in the past year or so, and I think some breakage is expected. It would be more productive to report this issue to them than complaining in a blog post they probably won't notice. They've been receptive to feedback in my experience. I reported a cataloging issue to them before and the issue was fixed. There's a link titled "Feedback" at the bottom of every catalog page.

Also, I'm not sure why the author is maintaining their own bibliographic database directly in Sqlite. Something like Zotero would probably be a better fit for them. (I'm aware Zotero uses Sqlite, that's not the point.) Zotero's bibliographic data importer works fine for the Library of Congress, even now.

Edit: I reported the bug to the Library of Congress myself:

> In the catalog, for seemingly every record, if "MARC record" is selected, "Download" is pressed, and any of "Dublin Core", "MODS", "MARC XML", or "Bibframe" are selected, a 404 error is returned. Those forms of cataloging records can not be downloaded and should be fixed. Thank you.

Edit #2: I got a reply within 5 minutes:

> Thank you for taking to the time to report this issue. We have noted the problem and are looking into it and hope to have a fix in a future release.

Edit #3: And rather than reply to a blog post in a place the author won't see, I've emailed the author about how he can report issues to the Library of Congress, and noted that I've already reported this bug.

Comment · 12 days ago
You could consider strategies used by engineers in high-income countries when faced with outsourcing/offshoring/immigration:

- Work in industries that require a local human, licensing, and/or citizenship. Law, defense, civil engineering, etc. It's not clear to me how robust these requirements are in the future, however.

- Set up legal barriers to prevent people from using AI to replace you. (The equivalent mostly didn't work for the engineers in high-income countries in my view. Note that I am not advocating for this, just listing it as an option.)

- Start your own business where you aren't directly doing engineering projects in return for money. Could be selling products direct to consumers instead, for example. Engineering can still be involved, of course. (Most likely to be successful in my view.)

Comment · 14 days ago
I have encountered the same problem myself. I've switched to linking to an image of a new disposable email address. Zero spam since then. (Actually, zero non-test messages total since then, but that's fine too.) I suppose that will work only as long as not too many people do it, though.

However, there are legitimate companies hiring through those threads. I know someone who got their current job from one of those threads. If you can avoid the spam, I think the benefits outweigh the downsides.

Comment · 17 days ago
Your experience is not universal.

I used modern Fortran in undergrad and grad research from 2011 to about 2015. I rarely ever encountered FORTRAN 77 back then, and never had to write any. I worked as an intern at NIST and LANL during that time too and it was modern Fortran there as well. At NIST, as far as I'm aware, that group had been using modern Fortran for probably a decade or more before I started in 2011.

I didn't have to write any FORTRAN 77 until 2025 in my current job when I was given a legacy code to work with.

Comment · 24 days ago
Scammers seem to use Hacker News heavily. Presumably the moderators keep the scam messages off Hacker News itself, but the moderators can't stop scammers from emailing people.

Posting on the "Ask HN: Who wants to be hired?" threads returns a ton of scams, particularly fake recruitment scams. Lightly obfuscating my email address like user at domain dot com didn't help much. Since changing my email address on there to a link to an image, I haven't got any scam messages or spam (yet).

Comment · 1 month ago
Location: United States (Open to any US location)

Remote: Yes, open to remote, hybrid, or in office

Willing to relocate: Yes

Technologies: Fortran, Python (including Matplotlib, Numpy, Scipy), OpenMP, Git/GitHub, Linux, Bash, others...

Résumé/CV: Available on request

Email: http://trettel.us/hn-jobs-email.png (to reduce spam, please type in the email address)

GitHub: https://github.com/btrettel

Personal website: http://trettel.us/

I'm Ben Trettel, a mechanical engineer with about 15 years of experience, specializing in computational fluid dynamics, multi-disciplinary design optimization, and verification and validation of computer simulations.

I am particularly interested in opportunities to build cutting-edge physical products where computational simulation and design optimization are key.

Please email me at the address above about only specific job opportunities that are matched to my skills and background. Do not email me about generic job opportunities that anyone can apply to or non-job opportunities like advertising your job board or giving me advice on my resume.

I am not interested in gig economy type contract work.

Recruiters: Send full details of the position including company and job description in the first email. As long as it meets the criteria above, do not ask if I am interested, just send the details.

Comment · 1 month ago
Comment · 1 month ago
Comment · 1 month ago
In my work (scientific or otherwise), I try to avoid dependencies if possible. That's not always possible, so a solution like Docker or NixOS is needed, but the problem can be improved a lot without a technical solution. Either feels like fighting an uphill battle though as most researchers think short term and just pick whatever is convenient in the moment.
Comment · 1 month ago

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