Readit NewsOn a serious note, I find this trend of shoving AI everywhere pretty disturbing. For instance, I used to enjoy Spotify’s “Discover Weekly” feature to find new music, but these days it’s offering so many AI generated songs the experience is pretty jarring.
struct Point {
x: f64,
y: f64,
}
impl Point {
fn x_mut(&mut self) -> &mut f64 {
&mut self.x
}
fn y_mut(&mut self) -> &mut f64 {
&mut self.y
}
}
I also disagree with the author that his rejected code:
fn main() {
let mut point = Point { x: 1.0, y: 2.0 };
let x_ref = point.x_mut();
let y_ref = point.y_mut();
*x_ref *= 2.0;
*y_ref *= 2.0;
}
I think the spirit of Rust's ownership rules is quite clear that when calling a function whose signature is
fn f<'a>(param: &'a mut T1) -> &'a mut T2;
This is often necessary for correctness (because there are many scenarios where you need to be guaranteed exclusive access to an object beyond just wanting to satisfy the LLVM "noalias" rules) and is not just an implementation detail: the language would be fundamentally different if instead the borrow checker tried to loosen this requirement as much as it could while still respecting the aliasing rules at a per-field level.
Yes, we have around 6,000+ assertions in TigerBeetle. A few of these were overtight, hence some of the crashes. But those were the assertions doing their job, alerting us that we needed to adjust our mental model, which we did.
Otherwise, apart from a small correctness bug in an internal testing feature we added (only in our Java client and only for Jepsen to facilitate the audit) there was only one correctness bug found by Jepsen, and it didn’t affect durability. We’ve written about it here: https://tigerbeetle.com/blog/2025-06-06-fuzzer-blind-spots-m...
Finally, to be fair, TigerBeetle can (and is tested) to survive more faults than Postgres can, since it was designed with an explicit storage fault model and using research that was not available at the time when Postgres was released in ‘96. TB’s fault models are further tested with Deterministic Simulation Testing and we use techniques such as static memory allocation following NASA’s Power of Ten Rules for Safety-Critical Code. There are known scenarios in the literature that will cause Postgres to lose data, which TigerBeetle can detect and recover from.
For more on this, see the section in Kyle’s report on helical fault injection (most Raft and Paxos implementations were not designed to survive this) as well as a talk we gave at QCon London: https://m.youtube.com/watch?v=_jfOk4L7CiY
I have followed TigerBeetle with interest for a while, and thank you for your inspirational work and informative presentations.
However, you have stated in several occasions that the lack of memory safety in Zig is not a concern since you don't dynamically allocate memory post startup. However, one of the defects uncovered here (#2435) was caused by dereferencing an uninitialized pointer. I find this pretty concerning, so I wonder if there is something that you will be doing differently to eliminate all similar bugs going forward?
> I was decent in math and Bill was brilliant, but I spoke from experience at Wazzu. One day I watched a professor cover the black board with a maze of partial differential equations, and they might as well have been hieroglyphics from the Second Dynasty. It was one of those moments when you realize, I just can’t see it. I felta little sad, but I accepted my limitations. I was OK with being a generalist.
> For Bill it was different. When I saw him again over Christmas break, he seemed subdued. I asked him about his first semester and he said glumly, “I have a math professor who got his PhD at sixteen.” The course was purely theoretical, and the homework load ranged up to thirty hours a week. Bill put everything into it and got a B. When it came to higher mathematics, he might have been one in a hundred thousand students or better. But there were people who were one in a million or one in ten million, and some of them wound up at Harvard. Bill would never be the smartest guy in that room, and I think that hurt his motivation. He eventually switched his major to applied math.
Even Paul admits, he was torn between going into Engineering or Music. But, when he saw his classmate giving virtuoso performance, he thought "I am never going to as great as this." So, he chose engineering.
Maybe it is a common trait in ambitious people.
Edits: Removed some misremembered information.
[1] https://www.amazon.com/Idea-Man-Memoir-Cofounder-Microsoft/d...
Rust even has tooling (clippy) that warns about unidiomatic code.