Max B

@tekknolagi
606 Followers
289 Following
1.5K Posts
Let's chat about compilers
websitehttps://bernsteinbear.com
githubhttps://github.com/tekknolagi/
bskyhttps://bsky.app/profile/bernsteinbear.com
Max B17h ago
Slava Pestov18h ago
Warning: Employees are strictly prohibited from stating undecidable problems while at the office. Violators will face severe penalties, up to and including possible non-termination
Max B2d ago

Also forgot to mention some small fun with Z3

https://bernsteinbear.com/blog/asm-z3/

Checking assembly with Z3

Short post today. New ZJIT contributor dak2 submitted a PR to fix an overflow bug in fixnum division in ZJIT. We did the division fine, but lied about the type of the result in the case of dividing FIXNUM_MIN by -1. You can see how this is special-cased in CRuby:

Max Bernstein
Max B2d ago

Inlining: the hard parts

https://bernsteinbear.com/blog/inlining-heuristics/

A survey of inlining heuristics

Compilers, especially method just-in-time compilers, operate on one function at a time. It is a natural code unit size, especially for a dynamic language JIT: at a given point in time, what more information can you gather about other parts of a running, changing system?

Max Bernstein
Max B6d ago
Incredibly fortunate to have noticed that a Joe's pizza opened in my neighborhood, gone in, gotten a slice, and learned that it opened today!!! Life is good
Max BMay 29
charlie cummingsMay 29

I wrote a blog post about Lunacy, my Lua 5.1 interpreter + JIT using Lazy Basic Block Versioning.

https://redvice.org/2026/lunacy/

Lunacy | Red Vice

A Lua 5.1 interpreter + JIT in Rust

Max BMay 29
Show threaddisregard Joe GroffMay 28
the Swift Performance team is also hiring another engineer, to work on optimization, code generation, and performance-oriented language features for the Swift compiler: https://jobs.apple.com/en-us/details/200661730-3401/swift-compiler-backend-engineer-languages-runtimes?team=SFTWR
Swift Compiler Backend Engineer, Languages & Runtimes - Jobs - Careers at Apple

Apply for a Swift Compiler Backend Engineer, Languages & Runtimes job at Apple. Read about the role and find out if it’s right for you.

Max BMay 27

New linear scan register allocator in ZJIT by @tenderlove !

https://railsatscale.com/2026-05-27-a-new-register-allocator-for-zjit/

A new Register Allocator for ZJIT

We recently landed a new register allocator in ZJIT. Learn about lifetimes, interference graphs, and linear scan — and why a global allocator unlocks features like method inlining.

Rails at Scale
Max BMay 20
I try to sell one (1) thing on Poshmark and all of a sudden I am drowning in spam and phishing. What the heck
Max BMay 18
Have just gone to the shop to buy Triscuits—or as I like to call them, Wheat Thicks
Max BMay 15
rail 🦊May 6
If you are interested in photography i seriously recommend you look into the works and life of Sergey Prokudin-Gorsky

He was a pioneer of color film photography in early 20th century and created some absolute bangers

It feels so weird and out of place to see sharp high-detail color photography and think "damn that looks reasonably modern, maybe a few decades old?" and then you're like "oh shit it's imperial russia" xd

https://en.wikipedia.org/wiki/Sergey_Prokudin-Gorsky#Gallery