Lef

647 posts

Lef

@elefthei

Proofs @Rise_MSR, @MSFTResearch. Compilers, Formal Verification, Cryptography. Previous: @Penn, @Bridgewater, @MIT.

Seattle, WA Entrou em Ağustos 2009

1.2K Seguindo1.2K Seguidores

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Lef@elefthei·29 May

🎉 Our paper “Structural Temporal Logic for Mechanized Program Verification” was accepted at OOPSLA 2025! We introduce Ticl, a program logic for compositional temporal proofs, beyond partial correctness, and directly over program syntax. #OOPSLA #Ticl 📄 arxiv.org/abs/2410.14906

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Lef@elefthei·21 Eki

@hackerdocc If it’s wrong why does it feel so right

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Eduardo@hackerdocc·20 Eki

it's always "formal verification is pointless cuz the {spec, type-checker} can be wrong" but never "coding is pointless cuz the {code, tests} can be wrong" or "type-systems are pointless cuz the {types, type-checker} can be wrong"

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Han Wang@handotdev·20 Eki

how it feels listening to this podcast

Lisan al Gaib@scaling01

Andrej Karpathy calls AI Agents slop "Overall, the models they are not there. And I feel like the industry [...] it's making too big of a jump and it's trying to pretend that this is amazing. And it's not—it's slop! And I think they are not coming to terms with it. And maybe they are trying to fundraise or something like that, I'm not sure what's going on."

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Lef@elefthei·20 Eki

Thanks to everyone who came to my talk on #Ticl a “Structural Temporal Logic for Mechanized Program Verification” at #OOPSLA. Despite being in the last day, we had a pretty good turn out!

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Lef@elefthei·19 Eki

Well this is embarrassing.

Michael Saxon@m2saxon

The viral new "Definition of AGI" paper has fake citations which do not exist. And it specifically TELLS you to read them! Proof: different articles present at the specified journal/volume/page number, and their titles exist nowhere on any searchable repository.

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Sebastian Angel@sebsgangel·13 Eki

If you are at OOPSLA 2025, don't miss @elefthei's presentation of our paper "Structural temporal logic for mechanized program verification" on Saturday October 18, at 3:15 PM (Singapore time). Paper: arxiv.org/pdf/2410.14906. Code: github.com/vellvm/ticl.

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Lef@elefthei·5 Eyl

From Wawa to WA.

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Alexander Hicks@alexanderlhicks·7 Ağu

I'm hiring at the EF: jobs.lever.co/ethereumfounda… If you're into Ethereum, cryptography, and formal verification, please get in touch! 🙂

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CAV@confCAV·25 Tem

Emina Torlak from @AWS delivered a wonderful keynote about the Cedar authorization engine. #cav2025

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Lef@elefthei·26 Haz

@lastland0 We can definitely schedule this for next fall. I always enjoy visiting Portland.

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Lef@elefthei·26 Haz

🎓 I have successfully defended my PhD. Deeply thankful to my advisors Sebastian Angel and Steve Zdancewic for their support and mentorship throughout this journey. Next I’m joining Microsoft Research and the RiSE group to work on AI assisted verification.

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joomy@joomy·19 Haz

excited that my team at @Bloomberg is supporting PhD students in certified programming (and other infra/sec topics too!) through a fellowship. 💻🛡️ includes stipend, tuition, and internship. timely for Rocq and proof assistant folks as science funding tightens. please apply! 📬

Tech At Bloomberg@TechAtBloomberg

#CFP: Applications for Bloomberg’s 2025-2026 #Infrastructure & #Security Ph.D. #Fellowship are now being accepted. Submission Deadline: Friday, July 18, 2025 (11:59 PM AoE) bloom.bg/3HLdfmO #InfoSec #supplychainsecurity #ProgramAnalysis #BugFinding

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Lef@elefthei·23 May

Reading in the editor is not the same as reading in the rendered PDF.

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Lef@elefthei·2 May

Theory is saying a DAG does not have cycles. Engineering is still adding a “visited” vector to the worklist algorithm because you know you will eventually hit a bug and it’s gonna be a pain to debug an infinite loop.

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Lef@elefthei·16 Nis

People using SMT solvers don’t know you can simply implement algebraic simplifications with smart constructors in 5x the time.

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Lef@elefthei·31 Mar

@MarisaVeryMoe Yes that is precisely what I was looking for! So staging an interpreter is good, but hard work. And the performance is still not as good as writing a compiler. I am using Rust so I will need quite a few tricks^TM to make this work. I am undecided but leaning don’t do it.

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Marisa "Long Middle Name Looks Cool" Kirisame@MarisaVeryMoe·31 Mar

@elefthei there's other work along the line, such as cs.purdue.edu/homes/rompf/pa…. Basically the benefit is to write code in a high-level style and get perf typically only available in a low-level style.

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Lef@elefthei·31 Mar

An interpreter is simply dynamic dispatch on a loop. A compiler trades dynamic dispatch for static dispatch. Can we have the cake (an interpreter) and eat it too (static dispatch)?

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Lef@elefthei·31 Mar

@MarisaVeryMoe Good idea! I imagine by using a language with partial evaluation you can get quite quite a bit of pattern matching done before getting the env. Then you are essentially dispatching only on references. Are you saying that practically the benefits are not that great?

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Marisa "Long Middle Name Looks Cool" Kirisame@MarisaVeryMoe·31 Mar

@elefthei With staging you can get compiler in the form of a staged definitional interpreter, which is a somewhat useful trick to reduce complexity (or to increase performance, depending on which way you look). A light-weight form of this is to have interp : term -> env -> value (...)

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Lef@elefthei·27 Mar

@aaroneline Idk I always saw this style in old ML papers

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Aaron Eline@aaroneline·27 Mar

@elefthei Old fashioned compared to?

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Lef@elefthei·27 Mar

I used to think ASTs with just two constructors UnaryOp and BinOp where old fashioned, but I think it actually saves a ton of lines of code (especially if using copilot).

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