Ian Petersen
Software Engineer at Meta
Seattle, Washington, United States
Summary
🤩
Rockstar🎓
Top SchoolIan Petersen is a C++-focused software engineer with over a decade of experience building and maintaining large-scale applications at Meta and Microsoft. He blends deep expertise in C++ and C# with decades-spanning fluency in both functional and object-oriented design, and a practical grasp of databases, client-side JavaScript, and build/tooling ecosystems. At Meta he continues to tackle low-level stability and portability issues, while his open-source contributions to high-profile projects like Facebook's folly and libunifex show a knack for fixing subtle UB, build-system quirks, and RTTI-free builds. Earlier roles ranged from technical principal at a startup—where he built an optimizing estimating engine and a GWT web UI—to leading the creation of a cross-browser JS widget library, reflecting strong product-minded engineering. Based in Seattle and educated at the University of Waterloo, he combines systems-level rigor with a pragmatic bent for shipping resilient code in complex, legacy-influenced codebases.
10 years of coding experience
13 years of employment as a software developer
Honours Bachelor's of Mathematics Major in Computer Science Option in Cognitive Science, Honours Bachelor's of Mathematics Major in Computer Science Option in Cognitive Science at University of Waterloo
French, English
Github Skills (9)
code-optimization10
c-language10
cprogramming-language10
exception-handling9
ios9
memory-management9
coroutines8
build-system8
error-handling8
Programming languages (7)
Github contributions (5)
facebookexperimental/libunifex
Aug 2020 - Jan 2023
Unified Executors
Role in this project:
Back-end Developer
Back-end DeveloperContributions:350 reviews, 61 commits, 177 PRs in 2 years 6 months
Contributions summary:Ian primarily contributed to fixing build errors and improving the codebase related to `libunifex`. Their work included resolving compiler warnings by removing unused lambda captures, introducing `unifex::type_index` to support building without RTTI, and suppressing vectorization warnings. The user also addressed compilation issues in test files, and updated copyright headers and deprecated files to ensure project consistency.
callbacksexecutorscoroutinefibersio-uring
facebook/folly
Mar 2018 - Apr 2022
An open-source C++ library developed and used at Facebook.
Role in this project:Back-end Developer
Back-end DeveloperContributions:7 commits in 4 years 2 months
Contributions summary:Ian primarily focused on improving the stability and compatibility of the `folly` C++ library. Their contributions included fixing undefined behavior in `Lazy.h`, adapting `coro`'s `Malloc.cpp` for older iOS versions, and resolving issues related to building with exceptions off. Furthermore, they addressed implicit conversion warnings and corrected an array length calculation in `ConvTest.cpp`. Their work demonstrates a strong understanding of C++ and its intricacies.
facebookcppc-library
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