HNHacker News
TopNewBestAskShowJobs

Arcuru

1,391 karma · joined March 16, 2018

https://jackson.dev
submissionscomments
Arcuru··on Bypassing the Branch Predictor
I love the `[[likely]]` and `[[unlikely]]` tags since they nicely encapsulate the Modern C++ philosophy.

1. They don't work that well.

2. The intended use case is that you'd label an unlikely branch that you want to speed up as `[[likely]]`, which is confusing.

They are certainly motivated by good intentions (like the HFT use-case as mentioned in TFA, I remember that talk too, I think I was a volunteer that year for CppCon), but even after knowing both of my points above _they were still added to the standard_.

Arcuru··on Ask HN: What Are You Working On? (Nov 2025)
https://eidetica.dev

I've been building a Decentralized Database built on top of syncing CRDTs, and recently got it to a point I can demo. It's definitely in a "proof-of-concept" stage though, known security holes and all.

I've been focused on building out the featureset and keeping everything unstable instead of trying to finalize each piece as I build it. It's the opposite of how I normally build things but I think it's been working pretty well for this.

I've written about it a few times, most recently "Using CRDTs + Sync as a Database" - https://jackson.dev/post/crdts_as_database/

Arcuru··on Why engineers can't be rational about programming languages
This person appears to have been "Languages Product Lead at Google", so they are very used to arguing about how important language choice is.
Arcuru··on At the end you use `git bisect`
Unfortunately I can't find the reference now, but I remember reading that even though binary search was first described in the 1940's, the first bug-free implementation wasn't published until the 1960s.

The most problematic line that most people seem to miss is in the calculation of the midpoint index. Using `mid = (low + high) / 2` has an overflow bug if you're not using infinite precision, but there are several other potential problems even in the simplest algorithm.

Arcuru··on CRDTs: Convergence without coordination
Shameless plug: I'm betting that a lot of applications could use some form of CRDT as a Database, which would allow a fully decentralized backend/database for local-first apps. So I've been building one.

Still working on good blog posts to explain and introduce it though.

https://github.com/arcuru/eidetica

Arcuru··on Liquibase continues to advertise itself as "open source" despite license switch
I agree that this isn't technically "open source", but the FSL blocks competing use. Is anyone here actually blocked from using Liquibase because of their switch to the FSL?
Arcuru··on Liquibase continues to advertise itself as "open source" despite license switch
What is their new license blocking you from doing?
Arcuru··on Ask HN: What are you working on? (October 2025)
Data hungry users/coaches probably already use something like TrainingPeaks[1], which has the more advanced features that you seem to want out of Strava. Might be worthwhile to check out if you're looking for ideas.

[1] https://www.trainingpeaks.com/

Arcuru··on Ask HN: What are you working on? (October 2025)
Eidetica is a decentralized database project that I've been working on that is finally in a somewhat usable state. It basically wraps CRDTs into a close to normal Database interface, with decentralized authentication, background sync, etc.

https://github.com/arcuru/eidetica

Arcuru··on Fast UDP I/O for Firefox in Rust
> Instead of starting from scratch, we built on top of quinn-udp, the UDP I/O library of the Quinn project, a QUIC implementation in Rust. This sped up our development efforts significantly. Big thank you to the Quinn project.

Awesome, so you sponsored them right?

https://opencollective.com/quinn-rs

Arcuru··on Dear GitHub: no YAML anchors, please
Its "pricing tiers" are "always free for OSS" and "TBD" for commercial use.

I like the things I depend on to actually have a funding model, so that's actually more appealing to me than something fully free.

Arcuru··on Why is your open source project still hosted on GitHub?
I've been mirroring all my public projects on GH and Codeberg using CI to keep things in sync, and add a note to my README's [1] explaining that both can be used. In practice the vast majority of OSS contributors are on Github so it's just not reasonable for smaller projects trying to grow to be anywhere else. Larger projects have enough pull that they can do what they want.

[1] https://github.com/arcuru/eidetica#repository

Arcuru··on YouTube addresses lower view counts which seem to be caused by ad blockers
I think you're not understanding. The claim is that view counts are down but revenue is not because people using ad-block previously did not contribute to revenue but did contribute to view count, and now they are not counted as either. So view counts are down and creators are getting the same ad money because they already earned no money from the adblocking people.

When channels are claiming their view count is dropping 30% but still earning the same amount of money, that would indicate that they are losing out on 30% of their potential revenue because of ad blockers.

Arcuru··on Spotify users ask for a setting to hide AI generated contents but they refuse
Is it possible to accurately identify "AI generated" songs? Or do they have to be labeled?
Arcuru··on Rug pulls, forks, and open-source feudalism
I understand why users get annoyed at "rugpulls", but if a company that is doing the vast majority of the work to develop and maintain a project is not financially sustainable they don't have that many options. An article like this really needs to include info about the financials.

I'm honestly curious since I've been considering how I license my large OSS projects lately [1], and I really do want to understand what would be "acceptable" here. Start more funding campaigns for the project? Work on it less? Sell merch? Openly communicate that they'll need to re-license without additional funding?

[1] - https://jackson.dev/post/oss-licensing-sucks/

Arcuru··on Removing Guix from Debian
> According to Debian's popularity contest (popcon) statistics, there are not quite 230 systems with Guix installed.
Arcuru··on Crush: Glamourous AI coding agent for your favourite terminal
There is a list of companies using the FSL at https://fsl.software/
Arcuru··on Giving Up on Element and Matrix.org
Oh interesting! I guess I read that post wrong, thanks for clarifying.

I would be interested in learning more context around this issue once you are able to share, so hopefully there will be a report/post/etc after the embargo lifts.

Arcuru··on Giving Up on Element and Matrix.org
This also comes as the organization is preparing a coordinated update to fix 2 CVEs in the protocol [1], that were originally reported 6 months ago.

[1] https://matrix.org/blog/2025/07/security-predisclosure/

Arcuru··on Tuning the Prusa Core One
I didn't realize Paul Lutus had an active blog! I would highly recommend not only reading this post but checking out the author. I read their book Confessions many years ago and it was one of the things that helped push me to look for fulfillment outside of tech.

It looks like he posted this so may see my comment. I just want to say thanks, I appreciate the things you've put out into the world.

Arcuru··on Is anybody using this private key?
Yea..sending it to the server makes it look sketchy. Even for my joke site[1] I make sure everything stays client side.

[1]: https://faxyourballs.com

Arcuru··on How we decreased GitLab repo backup times from 48 hours to 41 minutes
48 hours is a crazy amount of time to spend just to compress a git folder, it's only a couple GB. 41 minutes still seems like quite a long time.

Why aren't they just snapshotting and archiving the full git repo? Does `git bundle` add something over frequent ZFS backups?

Arcuru··on Compiler Explorer and the promise of URLs that last forever
They didn't store anything themselves since they encoded the full state in the urls that were given out. So the link shortener was the only place where the "database", the urls, were being stored.
Arcuru··on Google has most of my email because it has all of yours (2014)
The email monopolies annoy me the most when other apps assume you have gmail/apple/etc.

Notion recently launched email integration that only works with GMail, and all the marketing was basically "we added Email to Notion" instead of "we added _Gmail_ to Notion".

Arcuru··on Elvish – Scripting language and interactive shell
I've been using fish for many years now though I keep trying all these new shells.

Ultimately I've found that for my interactive shell I just want something widely supported and with easy syntax for `if` and `for` loops for short multi-line commands. For anything longer than that I just reach for real Python using either the `sh` or `plumbum` package.

I don't need the extra features very often, so I just run things in full Python where I'm already comfortable.

I've tried oils/ysh, elvish, xonsh, nushell, and while they are _fine_ I don't want to learn a different language that's not quite Python and not quite shell.

Arcuru··on Xiaomi MiMo Reasoning Model
From the paper, I was intrigued by how they handled their RL step for Code Data. They trained against hard but solvable code generation tasks by running unit testing. Is that training step done by the other models?

> Code Data For coding problems, we curate a high-quality training set comprising open-source datasets and our newly collected problem set. We remove problems without test cases. For problems with golden solutions, we exclude those where the golden solution failed to pass all test cases. For problems without golden solution, we discard problems where no test case can be solved in 16 rollouts of advanced reasoning models. Similar to math data, we utilize an SFT version of MiMo-7B to filter out easy problems that are perfectly solved in all 16 rollouts. This rigorous cleaning process yields 30K code problems.

> During each RL iteration, we evaluate thousands of problems to compute the rewards, with each problem potentially containing hundreds of test cases. To improve reward computing efficiency and eliminate GPU idle time, we developed an online judge environment that enables parallel execution of extremely high-volume unit tests.

Arcuru··on DeepSeek-Prover-V2
For a concrete example today, see https://openrouter.ai/openrouter/auto
Arcuru··on Librarians are dangerous
> it consumes a significant percentage of my municipal taxes.

That's interesting, I assumed it was only a small percentage everywhere. What percentage does it consume? I live in Seattle (King County) and our library system only costs 3.5% of our property taxes.

https://kcls.org/library-funding/

Arcuru··on A hackable AI assistant using a single SQLite table and a handful of cron jobs
I also want an OSS framework that lets me extend it with my own scripting/modules, and is focused around being an assistant for me and my family. There's a shared set of features (memory storage/retrieval, integrations to chat/email/etc interfaces, syncing to calendar/notion/etc, notifications) that should be put into an OSS framework that would be really powerful.

I also don't have time to run such a thing but would be up for helping and giving money for it. I'm working on other things including a local-first decentralized database/object store that could be used as storage, similar to OrbitDB, though it's not yet usable.

Mostly I've just been unhappy with having access to either a heavily constrained chat interface or having to create my own full Agent framework like the OP did.

Arcuru··on AI Coding and the Peanut Butter and Jelly Problem
Before LLMs there existed quite a few tools to try to help with understanding CLI options; off the top of my head there are https://github.com/tldr-pages/tldr and explainshell.com

LLMs are both more general and more useful than those tools. They're more flexible and composable, and can replace those tools with a small wrapper script. Part of the reason why the LLMs can do that though is because it has those other tools as datasets to train off of.

← PreviousPage 3 of 10Next →