David Simcha
Principle Software Engineer at Google
New York, New York, United States
Summary
👤
Senior🎓
Top SchoolDavid Simcha is a principal software engineer with 16 years of experience building high-performance systems for machine learning and large-scale data analysis, currently developing vector similarity search technology that powers ScaNN and Google Cloud Vertex AI Matching Engine. Trained as a bioengineer with a Ph.D. from Johns Hopkins, he blends rigorous statistical and ML research on biological data with a self-taught systems programmer’s expertise in low-level optimization, bit-twiddling and even assembly. At Google he rose through engineering ranks delivering production-grade performance and stability improvements, and his open-source contributions to the D language compiler and standard library include GC optimizations, compiler bug fixes, and efficient range primitives. Comfortable with both high-level math and hands-on implementation, he thrives on turning algorithmic ideas into efficient, scalable production code. Based in New York, he pairs academic depth with practical engineering rigor to solve demanding ML infrastructure problems.
16 years of coding experience
10 years of employment as a software developer
Johns Hopkins UniversityBachelor of Science (BS), Bioengineering and Biomedical Engineering, Bachelor of Science (BS), Bioengineering and Biomedical Engineering at Rutgers University
Stackoverflow
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318answers
192questions
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Github Skills (44)
garbage-collection10
algorithm10
algorithms10
struct10
bit-manipulation10
benchmarking10
language-agnostic10
collector10
data-structure10
garbage10
compiler-optimization10
data-structures10
compiler10
g10
sorting10
Programming languages (1)
Github contributions (5)
dlang/phobos
Dec 2009 - Dec 2012
The standard library of the D programming language
Role in this project:
Back-end Developer
Back-end DeveloperContributions:317 commits in 3 years
Contributions summary:David primarily focused on fixing bugs and improving the standard library of the D programming language. Their contributions included bug fixes related to the `VariantN` and `chain` range implementations, as well as an unlisted bug in the array library. The user also implemented the `indexed` range functionality, adding the support for creating a view of source range as if its elements were reordered according to provided indices. Additionally, the user added support for the `take` range, making the library code more efficient.
c-programmingmetatype-conversionphoneticsglossary
dlang/dmd
Nov 2010 - Feb 2012
dmd D Programming Language compiler
Role in this project:Back-end Developer & Performance Engineer
Back-end Developer & Performance EngineerContributions:37 commits in 1 year 3 months
Contributions summary:David contributed to the D programming language compiler, addressing a critical array resizing bug, adding performance benchmarks, and optimizing the garbage collector. They improved the GC's search algorithms, implemented bit shifting for multiplication, and refactored code for efficiency. The user's focus was on enhancing the compiler's performance and stability.
compilersnativedubdmdstandard-library
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