Honored to give my talk at #RubyKaigi this year! Slides are available here: blog.peterzhu.ca/assets/rubyk...

Code Layout Optimization Guided by Temporal Profiling Information by Marko Spasic This MoreVMs'26 talk improves the start up of applications by making sure that the code that's needed next is close by. Especially relevant for larger binaries. youtu.be/57KtH-w37B0

Code Layout Optimization Guided by Temporal Profiling Information by Marko Spasic This MoreVMs'26 talk improves the start up of applications by making sure that the code that's needed next is close by. Especially relevant for larger binaries. youtu.be/57KtH-w37B0

The Promise of Static Profiling: Exploring the Limits by Milan Cugurovic Another MoreVMs'26 talk. This one is on using machine learning to develop compiler heuristics. youtu.be/-14jvsxXb3w

The Promise of Static Profiling: Exploring the Limits by Milan Cugurovic Another MoreVMs'26 talk. This one is on using machine learning to develop compiler heuristics. youtu.be/-14jvsxXb3w

Hi! We build fast verilog simulators using just in time compilation. Our simulator outperforms existing verilog simulators by up to x100. verijit is a project by @cfbolz.bsky.social and Can Joshua Lehmann. Check out out demo video here: www. youtube.com/watch?v=PXgUsEjvAOY

Packrat Parsing at the Speed of Wasm by @dubroy.com Another MoreVMs'26 talk. Sound isn't great unfortunately, but it's still a very interesting topic for anyone building languages for the modern web! youtu.be/C2QxWtqlq9E

Packrat Parsing at the Speed of Wasm by @dubroy.com Another MoreVMs'26 talk. Sound isn't great unfortunately, but it's still a very interesting topic for anyone building languages for the modern web! youtu.be/C2QxWtqlq9E

We are going to put some of the MoreVMs'26 talks online. First up: How Many Compilers Is Too Many? A Look at V8’s History, Tradeoffs, and Architectural Choices By Leszek Swirski from Google's V8 team youtu.be/LpJ79MxplUk

Programování není jen kód, je to kultura! 💻📜 Rektor UK Jiří Zima udělil prestižní Cenu Bedřicha Hrozného za tvůrčí počin a my máme obrovskou radost, že ji získal docent Tomáš Petříček z naší @mff.unikarlova.cuni.cz! 🏆

We are going to put some of the MoreVMs'26 talks online. First up: How Many Compilers Is Too Many? A Look at V8’s History, Tradeoffs, and Architectural Choices By Leszek Swirski from Google's V8 team youtu.be/LpJ79MxplUk

C interpreters underlie many of our most widely used language implementations -- but they're slow. Wouldn't it be great if we could turn them into JIT compiling VMs? This video shows what happens when we do just that to the normal Lua VM (first) and "yklua" (Lua w/JIT, second).

I'm starting at Datadog today!

Just received a Most Notable Paper Award for our paper “Cross-language compiler benchmarking: are we fast yet?” published at the Dynamic Languages Symposium 2016. Congratulations to my co-authors @stefan-marr.de and Hanspeter Mössenböck!

GraalWasm just got faster! 🔥 The new threaded interpreter delivers significantly better interpreter performance. In interpreter benchmarks, total execution time is reduced by 5-40%! Details: github.com/oracle/graal...

New post on the @ohmjs.org blog — Inside Ohm's PEG-to-Wasm compiler → ohmjs.org/blog/2026/03... v18 is now more than 50x faster for real-world grammars while using about 10% of the memory 🔥 …this post goes into the details of how it's built.

Interesting theme that came up in a few talks (incl. mine) was flat/packed tree representations. Michael Vollmer (Univ. of Kent) has done tons of interesting work in this area: recurial.com

Less than a week until ‹Programming› 2026 in Munich (March 16–20)! What’s ahead: - 4 days of deep-dive sessions. - Workshops including MoreVMs, PX/26, SCLIT, VIMPL, and Substrates. - Networking in the heart of Bavaria. We can’t wait to see you there! Final details: 2026.programming-conference.org

I hate having to consult a decoding table when reading dense text. That's as true for abbreviated author names or numbers as it is for "Greek" letters instead of names I may have a chance to remember. It's also true for general abbreviations. A few can be ok. Too many and I'll probably get lost.

Oh wow, someone is scraping researchr and sends "we'll organize your travel" spam. Ugh.

The deadline of the ICOOOLPS workshop is soon! Want to talk about language implementation challenges, experiences, and/or research? It will be in sunny Brussels end of June! 2026.ecoop.org/home/ICOOOLP...

The deadline of the ICOOOLPS workshop is soon! Want to talk about language implementation challenges, experiences, and/or research? It will be in sunny Brussels end of June! 2026.ecoop.org/home/ICOOOLP...

A bit late and not yet finalized, but our program for MoreVMs'26 is online. Early registration deadline is in a few hours, but will remain open afterwards still. Join us in Munich for a day of talks around language implementation! 2026.programming-conference.org/home/MoreVMs...

A bit late and not yet finalized, but our program for MoreVMs'26 is online. Early registration deadline is in a few hours, but will remain open afterwards still. Join us in Munich for a day of talks around language implementation! 2026.programming-conference.org/home/MoreVMs...

Final 24h! Early bird for #prog26 ends tomorrow, Feb 20. Don't miss the art & science of programming in Munich (Mar 16–20)! Register: 2026.programming-conference.org Submit to the Substrates workshop: 2026.programming-conference.org/home/substra...

ISMM (International Symposium on Memory Management) is going to hosted at PLDI'26. Please consider submitting your awesome papers on memory management by 27th March: conf.researchr.org/home/ismm-20...

Overheard some non-technical people: "Oh, that's all AI, I wouldn't touch that." It was about some finance scam app...

Programming Language Implementation: In Theory, We Understand. In Practice, We Wish We Would. In about a month, on March 9th, I'll give my inaugural lecture. I'll probably complain about the complexity of modern programming language implementations... stefan-marr.de/2026/02/prog...

We are organizing the third edition of the "Fuzzing and Software Security Summer School 2026", at NUS on 26th–29th May 2026. We have a stellar set of speakers and will also have a Hackathon. Please share, and/or consider joining! fuzzingsummerschool.github.io/index.html

Programming Language Implementation: In Theory, We Understand. In Practice, We Wish We Would. In about a month, on March 9th, I'll give my inaugural lecture. I'll probably complain about the complexity of modern programming language implementations... stefan-marr.de/2026/02/prog...

Just passed by this fun mural www.cologne-tourism.com/arts-culture...

Python, Is It Being Killed by Incremental Improvements? In October, I gave a talk at SPLASH, which is now online. Is the title click bait? Click the link below, watch the recording, and find out! Spoiler: I think Python has a problem but we can do something about it. stefan-marr.de/2026/01/pyth...

Python, Is It Being Killed by Incremental Improvements? In October, I gave a talk at SPLASH, which is now online. Is the title click bait? Click the link below, watch the recording, and find out! Spoiler: I think Python has a problem but we can do something about it. stefan-marr.de/2026/01/pyth...

After working on ZGC for a decade, I’m happy to announce that I’m publishing a book about ZGC in JDK 25. It ships 22 May (www.taylorfrancis.com/books/mono/1...) and is being published by Taylor & Francis. You should get a copy if you want to learn more about ZGC. It’s available for pre-order now.

Very cool research made it into TruffleRuby!

[email protected] and I are looking for a PostDoc to work on our EPSRC Project "INDIMO: Invariant Discovery and Monitoring for Message-Passing Programs". If you know someone, or are interested, please reach out! A few details here: jobs.royalholloway.ac.uk/Vacancy.aspx...

[email protected] and I are looking for a PostDoc to work on our EPSRC Project "INDIMO: Invariant Discovery and Monitoring for Message-Passing Programs". If you know someone, or are interested, please reach out! A few details here: jobs.royalholloway.ac.uk/Vacancy.aspx...

Koichi gave a talk at VMIL about it: youtu.be/pqDMne677Ww?... The code is at github.com/ko1/astro naruby uses the Prism C API for parsing: github.com/ko1/astro/tr...

Last year I had the pleasure to review and contribute to this paper by @ko1s.bsky.social: atdot.net/~ko1/activit... It's a tiny framework to partial evaluate AST interpreters written in C. The paper uses the example of a minimal subset of Ruby called naruby (Not A Ruby).

More PLISS speakers announced! pliss.org/2026/

Had a good inspiring break? Tell us about your latest ideas on language implementations, compilers, and VMs: 2026.programming-conference.org/home/MoreVMs... Can be just a short abstract, or something slightly more technical if preferred. Deadline in about a week, Jan 12th.

Had a good inspiring break? Tell us about your latest ideas on language implementations, compilers, and VMs: 2026.programming-conference.org/home/MoreVMs... Can be just a short abstract, or something slightly more technical if preferred. Deadline in about a week, Jan 12th.

ZJIT is available starting in Ruby 4.0! Please try it out on your test suite, maybe in a staging environment, and let us know how it goes! railsatscale.com/2025-12-24-l...

Last workday of the year for me. Down to 30 unread emails. Let's see what the new year brings 🙈

Another example of rankings being silly. Before: 4 After: 10 Yes scoped to my personal interest, but still. These "emery berger rankings" are silly.

Some university administrator set a deadline for Dec. 23rd 23:59.

I can't quite believe that we're now announcing the eighth Programming Language Implementation Summer School (PLISS), but we are --- in May next year, if you want to learn more about programming language implementations, this is the place to come!

How can we know whether a profiler is accurate? Humphrey's presentation of our paper "Divining Profiler Accuracy: An Approach to Approximate Profiler Accuracy Through Machine Code-Level Slowdown" is now online: www.youtube.com/watch?v=U-7P...

How can we know whether a profiler is accurate? Humphrey's presentation of our paper "Divining Profiler Accuracy: An Approach to Approximate Profiler Accuracy Through Machine Code-Level Slowdown" is now online: www.youtube.com/watch?v=U-7P...

Tomorrow end of day, anywhere on earth, is our "pre-holiday" deadline for MoreVMs: 2026.programming-conference.org/home/MoreVMs... Submit your papers, talk proposals, or experimental setups now and enjoy some time off!