Mara Bos

Rust dev, Electronics engineer, Author, Hexcat, RustNL, RustWeek organizer, ADHD, Polyamorous, Lesbian, She/Her

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npub169tpmvdvk8pew2wtcza3e48kltlupszd2juv4pteh8akgykrtwhsefjk89

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nprofile1qqsdz4sakxktrsuh989upwcu6nm04l7qcpx4fwx2s4umn7myztp4htcpz3mhxue69uhhyetvv9ujuerpd46hxtnfduqs6amnwvaz7tmwdaejumr0ds96v37j

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relay.damus.io

nos.lol

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npub169tpmvdvk8pew2wtcza3e48kltlupszd2juv4pteh8akgykrtwhsefjk89

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Last Notes

2026-08-31 16:35:43 GMT

We lowered the ticket prices for RustWeek!
Individual tickets are now 199 instead of 249 euro. ✨
Additionally, we added a checkbox for an extra 100 euro discount, bringing the ticket price to just 99 euros for those who can't afford the full price. 💛
https://media.hachyderm.io/media_attachments/files/117/191/085/351/417/262/original/e1d62945186135ab.png

2026-08-11 12:03:40 GMT

I was asked recently about the cost of running a (#rustlang) conference and why the ticket prices are what they are. We figured we can just publicly share the numbers for RustWeek, in the name of #transparency. :)
RustWeek has many subevents (conference, hackathon, unconference, workshops, Rust All Hands, etc.), but I've tried to extract just the two day conference part of RustWeek 2026:
Venue rent: € ~50k
Lunch, snacks, drinks two full days: € ~130k (incl. catering services and exclusive access to 1000 person restaurant all day)
A/V services: € ~30k (incl. livestreaming, professionals operating the cameras/microphones/screens in the rooms, editing the recordings, etc.)
Stuff we set up at the venue: € ~20k (sponsor booths, entertainment, banners, stickers, wifi, etc.)
Travel compenstation for speakers: € ~10k
External services: € ~25k (accounting, registration & payment, event management, insurance, etc.)
Miscelaneous: € ~15k
This adds up to roughly € 280k for just the two conference days. (The total for all of RustWeek is ~€ 400k.)
The money we get from sponsors covers roughly half of the costs. The other half has to be covered by tickets.
We are currently the biggest Rust conference with 850+ attendees. We give free tickets to all the speakers and volunteers, which is almost a hundred people total. The sponsor packages also include a total of roughly 100 tickets. That leaves ~650 sold tickets.
Those are roughly 250 corporate tickets (~410 euro after tax), 300 individual tickets (~190 euro after tax), and 100 student tickets (~30 euro after tax). Accounting for the various discounts (early bird, discount codes, etc.) and overhead, this leaves us with roughly 140k.
Those student tickets are sold at a significant loss, but it's very important to us to not just run this conference for those with a well paid job.
Setting the ticket prices is very tricky, because you have to set them a year in advance, before you know what amount of sponsorship to expect. We only find out *after* the event if we guessed correctly or if we ran at a loss. This year, we made a (very small) profit, which we'll spend on our Rust Maintainers Team: https://rustnl.org/maintainers/

2026-07-30 14:28:46 GMT

Imagine organizing a Rust conference and having zero women on stage. That's just embarrasing. https://oxidizeconf.com/

2026-06-29 17:37:36 GMT

Now I can finally commit Rust code crimes legally. 😌
https://media.hachyderm.io/media_attachments/files/116/834/606/073/734/571/original/a34841df3e79f145.png
https://media.hachyderm.io/media_attachments/files/116/834/606/353/480/120/original/9dfda45bd5d99083.png

2026-06-27 09:12:21 GMT

Can't wait for this new release. 🎮
https://media.hachyderm.io/media_attachments/files/116/821/296/032/161/944/original/2902a77d85d16a2c.png

2026-06-21 09:05:38 GMT

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Look at how precise this thing is. Unbelievable.
https://media.hachyderm.io/media_attachments/files/116/787/296/048/206/623/original/11c9e03ab2c1b91e.png
https://media.hachyderm.io/media_attachments/files/116/787/296/736/632/038/original/9b2e41f4d0075b38.png

2026-06-21 09:04:57 GMT

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More serously, this machine is magic. It somehow cuts wood without charring the edges?
https://media.hachyderm.io/media_attachments/files/116/787/291/626/957/094/original/d4c90e706a33077d.png
https://media.hachyderm.io/media_attachments/files/116/787/291/958/832/822/original/b1078b3c9b681f88.png
https://media.hachyderm.io/media_attachments/files/116/787/292/368/631/784/original/d6a1b04cc2560b36.png

2026-06-21 09:03:51 GMT

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I feel so powerful now, being able to inflict the wonders of Comic Sans onto every single object in my house.
https://media.hachyderm.io/media_attachments/files/116/787/288/917/104/214/original/085560d17ef4e142.png
https://media.hachyderm.io/media_attachments/files/116/787/289/656/676/587/original/a02ee18f9eb1eee0.png

2026-06-21 09:03:07 GMT

Someone made the mistake of getting me a UV laser engraving machine.
...
(It was me.)
https://media.hachyderm.io/media_attachments/files/116/787/285/003/978/720/original/995302da22dbe1bf.png
https://media.hachyderm.io/media_attachments/files/116/787/285/417/056/865/original/a26cfc413a09241f.png
https://media.hachyderm.io/media_attachments/files/116/787/286/144/533/070/original/7bb5b5ee8763ecb6.png

2026-06-02 14:57:21 GMT

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1. "Hail Miri" (Hail Mary)
https://media.hachyderm.io/media_attachments/files/116/681/096/090/167/357/original/d25ecac258b8bd8a.png

2026-06-02 14:57:01 GMT

Just like last year, we replaced a whole wall of movie posters with our own punny movie posters at the cinema where RustWeek 2026 took place. I designed seven new posters for this year's event. See the thread below 👇
https://media.hachyderm.io/media_attachments/files/116/681/094/605/114/152/original/d00adebec374c980.png

2026-05-28 19:33:56 GMT

I'm really excited that my assert_matches!() macro is finally stable. I can't believe it's been five years since I added it to (unstable) Rust. Time flies. https://github.com/rust-lang/rust/pull/82770
#nevent1q…xx4u

2026-05-16 11:11:04 GMT

There are several proposals for a first version of an LLM policy for the Rust project, which haven't even been accepted/merged yet, and yet there are now pro-AI people outraged because we're banning AI, and anti-AI people outraged because we're allowing AI. What a day. :)
I promise you many of us care very deeply about the ethical impacts of AI. The project is not banning any discussion topics, but we do want to keep some GitHub threads focussed to avoid them derailing into discussions we're already having in other places.

2026-05-15 19:04:41 GMT

Today is the 11th birthday of Rust 1.0! 🥳 🎂 🦀

2026-05-14 10:51:52 GMT

Do you or does your employer have too much money? RustWeek can help! You can now use discount code "rosebud;!;!;!;!;!" to increase the RustWeek ticket price to 10,000 euro.
Only a few days left!
https://event.onliveevent.nl/rustweek-2026

2026-05-08 20:19:13 GMT

"We have been made aware of a potential incident and are shutting down all issuance."
😬
https://letsencrypt.status.io/

2026-04-16 11:48:49 GMT

Half a year later, I'm *very* excited to report that we got initial funding and have hired our first Rust maintainers!
RustNL's Rust Maintainers Team now has two full time maintainers, one intern, and five part-time maintainers, now stably employed to continue their invaluable maintenance work that is crucial for Rust’s long-term sustainability.
https://rustnl.org/maintainers/
#nevent1q…6kta

2026-03-31 19:50:30 GMT

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Fun fact: Just for RustWeek, the internet infrastructure in the venue gets a big (temporary) upgrade with extra wifi access points that get installed in the restaurant and in the cinema rooms, because you all bring more than one device on average and use a lot more bandwidth than the average cinema visitor.
https://media.hachyderm.io/media_attachments/files/116/325/516/409/846/496/original/ebb51834b7c378ee.png

2026-03-30 17:35:15 GMT

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Next to three tracks in big cinema rooms, we will also have an amazing hallway track. We rented out the entire 1000-person capacity restaurant attached to the cinema!
This space is available all day during the conference, has many six-person booths with power sockets, and even a nice outdoor space.
https://media.hachyderm.io/media_attachments/files/116/319/328/503/921/257/original/7f1caac21237e1cf.png

2026-03-29 17:29:41 GMT

Did you know that RustWeek 2026 is held in one of the largest cinema's of the Netherlands? This means: extremely comfortable seats, great air conditioning, perfect audio, and a very big screen: over 280m², the 2nd largest in the country! ✨
Don't forget to buy your tickets! https://2026.rustweek.org/
https://media.hachyderm.io/media_attachments/files/116/313/644/559/369/160/original/a584d89bb7541247.png

2026-03-03 09:18:16 GMT

website: choose a password
me: ,p?YG;qtChe?DAh@&o]`zg"k,
website: sorry, not strong enough. needs to contain a number.

2026-02-16 18:45:16 GMT

After carefully reading and ranking a record number of 185 submissions from 148 speakers, we finally finished the talk selection for RustWeek 2026!
I'm *really* excited about the lineup! Check it out here: https://2026.rustweek.org/blog/2026-02-13-speakers-announced/
Don't forget to buy your ticket! See you in Utrecht!

2026-01-27 16:47:36 GMT

If you want a Rust button and a discount code for RustWeek, come find me at FOSDEM this weekend!
I now have bright pink hair, so should be easy to find :)
#rustlang #rustweek #fosdem
https://media.hachyderm.io/media_attachments/files/115/968/076/644/194/775/original/ff0320837ceef15c.jpeg

2025-11-19 07:33:07 GMT

#rustlang hot take: We should rename .unwrap() to .or_panic(). (And .expect() to .or_panic_with().) "Unwrap" is a terrible name for the panicking function, especially since we also have things like .unwrap_or() and .unwrap_or_default() which never panic.

2025-11-13 13:28:12 GMT

🦀 I've improved the implementation behind all the string formatting macros in Rust: println!(), panic!(), format!(), write!(), log::info!(), and so on. (That is, everything based on format_args!().) They will compile a bit faster, use a bit less memory while compiling, result in smaller binaries, and produce more efficient code! 🎉
'Hello world' compiles 3% faster and a few bigger projects like Ripgrep and Cargo compile 1.5% to 2% faster. And those binaries are roughly 2% smaller. 🎊
This change will be available in Rust Nightly tomorrow, and should ship as part of Rust 1.93.0 in January.
#rustlang
https://media.hachyderm.io/media_attachments/files/115/542/502/543/990/441/original/3b0f8e97d0518120.png

2025-10-14 15:19:55 GMT

I'm excited to share what I've been working on with @nprofile…f6vk: RustNL's #rustlang Maintainers Fund!
Many people and companies contribute to Rust, but there are fewer and fewer paid positions for general maintenance (reviews,cleanups,etc). We need to fix that.
General maintenance is one of the most fundamental jobs in an open source project, but is one of the hardest to get paid for. Adding new features gets you promoted; keeping the lights on does not.
But everything depends on it. Code needs reviews, cleanups, docs. New contributors need mentors, etc.
‪
A significant number of Rust maintainers who got paid for that have lost or quit their job recently. Due to RTO policies, a shift in responsibilities, budget cuts, and/or burnout. This is already quite noticable in the Rust project: longer review queues and more technical debt. This is a problem.
‪
Through RustNL, the non-profit foundation behind the largest Rust conference (RustWeek) and the Rust Project's All Hands, we are setting up a fund to provide stable jobs for Rust maintainers. We want to employ six full-time maintainers in 2026.
‪
Additionally, we'll provide internships and mentorship, to help retain promising new contributors. Not only do we need to make sure the current generation of maintainers doesn't burn out, we need to work on the next generation of maintainers too.
‪
What we need now is companies who rely on Rust to step up and contribute financially. Having your business rely on the work of unpaid volunteers is not sustainable in the long term. It's a risk.
And if your company contributes to Rust, keeping the project well-maintained will accelerate your work.
‪
Over the last few months, we have spoken to the Rust Foundation and several big companies about our plans. The input we've received and the positive reactions so far makes us believe we can make this happen. Today, we are publishing our plans for a wider audience, in search for the required funding.
‪
If your company is interested in funding Rust maintainers, please reach out to me or @nprofile…f6vk!
You can find our sponsors prospectus here: https://rustnl.org/resources/Rust-Maintainers-Fund.pdf
Let me know if you want to talk! 💛
(Message me through Mastodon, Rust Zulip, or email: [email protected])
https://rustnl.org/fund/

2025-10-11 16:30:11 GMT

Getting called out in front of hundreds of people for my programming crimes. #eurorust @nprofile…vws7
https://media.hachyderm.io/media_attachments/files/115/356/479/956/288/343/original/c86c25d45d205728.jpg

2025-07-17 11:43:51 GMT

Reddit keeps showing me ads: "Find your perfect gamer boyfriend. Use our new dating app for gamers".
You'd think it'd be easier to correctly profile my account that's joined zero gaming subreddits and several lesbian subreddits. 🤔

2025-06-07 11:53:17 GMT

I guess this explains all the segfaults I've gotten from Rustc recently. 😅
https://media.hachyderm.io/media_attachments/files/114/641/940/069/732/836/original/62976551b343eed9.png

2025-05-18 09:50:10 GMT

Thank you all so much for coming to #RustWeek. I had a fantastic week. Organizing it was so much fun. Seeing all the ideas come to life and watching hundreds of people having a good time was magical. ✨️ See you next time.

2025-05-13 20:20:46 GMT

Here are all the posters I designed for RustWeek 2025!
1. "Box<impl Future>" (Back tot the Future):
#rustweek #rustweek2025
https://media.hachyderm.io/media_attachments/files/114/502/369/385/830/139/original/14364d1e45402b22.jpg

2025-05-12 17:28:49 GMT

For those not attending in person: You can watch the #RustWeek conference live from anywhere! Check out our free livestream!
We start tomorrow at 9:30 CEST!
Livestreams: https://rustweek.org/live
Schedule: https://rustweek.org/schedule

2025-04-16 14:13:52 GMT

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This is for #RustWeek and the #rustlang All-Hands. :)

2025-04-16 14:12:40 GMT

☁️📊
https://media.hachyderm.io/media_attachments/files/114/348/048/854/758/334/original/840ee1051ac7c891.jpg

2025-03-31 22:02:17 GMT

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And now the humans have joined in. "Hey I think you made an error. I'm getting a lot of emails." "Yeah me too."

2025-03-31 21:51:48 GMT

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It looks like they actually used the invoicing email addresses of their customers. So many of the emails are accounting systems responding with things like 'error: missing pdf invoice' 'error: no attachment found', etc. with instructions on how to send them proper invoices.
Each of which is then triggering other bots going "your ticket has been filed!" and "thanks for your message! we will reply to you within three working days!".

2025-03-31 21:41:37 GMT

A Dutch hardware store just sent out a newsletter with a `from` address that is actually their (accidentally public!) mailing list that forwards to all their customers. So, every single autoresponder message from any of their customers is getting forwarded back to all their customers, triggering more autoresponder messages. There's also ticketing systems replying with "your ticket has been filed" to each other, "this email address no longer exists" errors spamming back and forth, and so on.
Tomorrow morning, a lot of people are going to wake up with very full inboxes. 😬

2025-03-29 18:56:26 GMT

If you could go back in time and change #rustlang before it hit 1.0, what would you change?

2025-02-01 14:38:49 GMT

If you want #rustlang stickers, come find me at #fosdem today or tomorrow!

2024-11-20 12:18:42 GMT

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@nprofile…y42l That's just how thread local variables work. Every thread gets its own version.

2024-11-20 11:41:29 GMT

🦀 My "inheriting thread locals" aka "thread spawn hook" feature has been merged into #rustlang as an unstable feature! You can use it to automatically copy thread local state into new threads, which wasn't possible before. Available on Rustc nightly tomorrow!
https://github.com/m-ou-se/rfcs/blob/thread-spawn-hook/text/3642-thread-spawn-hook.md
https://media.hachyderm.io/media_attachments/files/113/515/093/038/237/397/original/50ba3f55b9f4c3c0.png

2024-11-08 18:35:08 GMT

My (semi-)basement is starting to feel like a cool hacker space ✨️
(Installed a ton of new lights last weekend. 🌈)
https://media.hachyderm.io/media_attachments/files/113/448/772/813/701/476/original/ed28899ce7e4d949.jpg

2024-10-11 09:23:59 GMT

#eurorust2024
https://media.hachyderm.io/media_attachments/files/113/288/060/931/192/756/original/1bc26299926e43be.jpg

2024-10-03 15:25:27 GMT

🦀 I'm so excited we can now finally share the (preliminary) schedule! We've been working hard to plan an amazing week of Rust next year. Hope to see you all in Utrecht! 😊
https://rustweek.org/
#rustlang #rustweek
https://media.hachyderm.io/media_attachments/files/113/243/956/746/107/562/original/d1f8e92abf5d29e6.png

2024-08-13 17:36:52 GMT

Reminder that my book—Rust Atomics and Locks—is freely available online: https://marabos.nl/atomics/ 😊
(If you read it, please leave a review on https://www.goodreads.com/book/show/63291820-rust-atomics-and-locks)
#rustlang

2024-07-19 09:20:38 GMT

https://media.hachyderm.io/media_attachments/files/112/812/414/172/284/452/original/9c6fe00a4104a69a.png

2024-07-02 19:20:55 GMT

Apparently the concept of users who are not men is "too controversial" in the SerenityOS project, "as to not alienate anyone*".
(*Anyone, as long as you go by he/him, of course.)
https://github.com/SerenityOS/serenity/pull/24647
https://media.hachyderm.io/media_attachments/files/112/718/512/166/370/868/original/3ce610508e3b3f37.png

2023-11-05 10:49:15 GMT

If `a += b` is `a = (a + b)` and `a *= b` is `a = (a * b)`, then `a == b` should be `a = (a = b)`. 😌

2023-07-27 08:48:44 GMT

🦀 Has binary size ever been a big issue for you in Rust? Is this an area that needs more active work? What would you like to see happen?
#rustlang

2023-07-03 19:41:47 GMT

✂️ New hair! 🌈
https://media.hachyderm.io/media_attachments/files/110/651/835/316/183/786/original/cf1b801590424872.jpg
https://media.hachyderm.io/media_attachments/files/110/651/847/431/255/870/original/fd932a91a83ba4e1.jpeg
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