Leo Osvald
Senior Software Engineer at Meta
San Francisco Bay Area United States
Summary
👤
Senior🎓
Top SchoolLeo Osvald is a software engineer and compiler specialist with ~14 years of experience bridging research and production, currently architecting cross-layer AI compiler optimizations at Meta in the San Francisco Bay Area. He has a strong academic pedigree (PhD work at Purdue) with publications on tensor-layouts, capability-based types, and borrow-checker modeling, and has translated that research into production wins—delivering up to 18x speedups and double-digit QPS/latency gains across model and recommendation workloads. Leo led a large OCaml-to-Rust modernization of the Hack/HHVM compiler and has made substantive contributions to the well-known facebook/hhvm project, demonstrating deep expertise in VM internals, type systems, and code generation. He combines systems-level performance engineering (LLVM IR, backend codegen) with high-level language design, and has a track record of founding safety and extensibility models adopted across large codebases. An active open-source and contest participant, he also serves as a reviewer and judge for top conferences and competitions, reflecting both technical leadership and community engagement. Colleagues rely on him for solving hard cross-stack bottlenecks where language design, compilers, and hardware meet.
14 years of coding experience
8 years of employment as a software developer
(high school), Mathematics and Computer Science, (high school), Mathematics and Computer Science at XV. gimnazija (Zagreb, Croatia)Master’s Degree, Computer Science, GPA: 3.66 / 4.00, Master’s Degree, Computer Science, GPA: 3.66 / 4.00 at Purdue UniversityB. Sc, Computing; Electrical Engineering and Computing, B. Sc, Computing; Electrical Engineering and Computing at University of Zagreb
English, Italian, Croatian
Github Skills (10)
type-system10
code-generation10
parser10
compiler-design10
parsing10
parse10
abstract-syntax-tree9
code-analysis9
compiler9
rust8
Programming languages (6)
Github contributions (5)
facebook/hhvm
Sep 2018 - Sep 2022
A virtual machine for executing programs written in Hack.
Role in this project:
Back-end Developer & Compiler Engineer
Back-end Developer & Compiler EngineerContributions:287 commits in 4 years
Contributions summary:Leo primarily contributed to the development and maintenance of the HHVM (Hack Virtual Machine) compiler, specifically focusing on features and improvements related to type systems and code generation. The commits involved modifying code in various parts of the compiler to incorporate new features or fix bugs, including adding support for features such as context constants. The user also demonstrated expertise in compiler internals by working on the type checking and analysis phases. This work included contributions to the parser, and the various intermediate representations of the code, indicating a strong understanding of the compilation pipeline.
hacklangphpvirtual-machineprogramshhvm
losvald/yasnippet-snippets
Feb 2015 - May 2018
Contributions:26 pushes in 3 years 3 months
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