Justin Borromeo
Software Engineer at Glean
San Francisco, California, United States
Summary
👤
Senior🎓
Top SchoolJustin Borromeo is a software engineer with 11 years of experience building high-performance search and data systems, currently working on search platform reliability and evaluation at Glean in San Francisco. He brings a strong backend and performance engineering background from roles at Google and contributions to Apache Druid—where he implemented time-ordered scans, benchmarking tools, and stability fixes—to optimize memory and query performance. A University of Waterloo Mechatronics graduate with an AI option, he blends systems engineering with research experience in information retrieval and FPGA-based neural acceleration. Comfortable in both production infrastructure and research codebases, he has a track record of shipping measurable performance improvements and surfacing hard-to-find flakiness in tests. An under-the-radar detail: he pairs systems-level optimizations with reproducible benchmarking work, underscoring a data-driven approach to reliability.
11 years of coding experience
3 years of employment as a software developer
Bachelor of Applied Science - BASc, Mechatronics Engineering with Option in Artificial Intelligence, Bachelor of Applied Science - BASc, Mechatronics Engineering with Option in Artificial Intelligence at University of WaterlooHigh School, High School at Bayview Glen
English
Stackoverflow
1,281reputation
88kreached
3answers
23questions
Github Skills (20)
benchmark10
benchmarking10
apache-druid10
java10
javas10
performance-optimization10
testing9
database-optimization8
optimization8
optimisation8
sql8
query-optimization8
azure6
sorting6
python6
Programming languages (7)
Github contributions (5)
apache/druid
Jan 2019 - Jun 2019
Apache Druid: a high performance real-time analytics database.
Role in this project:
Back-end Developer & Performance Engineer
Back-end Developer & Performance EngineerContributions:23 commits, 32 PRs, 112 comments in 4 months
Contributions summary:Justin primarily focused on performance improvements and new feature implementation related to the scan query functionality within the Druid database. They developed a scan benchmark and made several iterations to benchmark parameters and segment sizes to improve memory usage and performance. The user also implemented time ordering on scans, a significant addition, including tests and integration with SQL. They also contributed to optimizing the index by replacing global flags with getters and addressed flakiness in tests, improving the overall stability.
real-timebig-datadruiddatabasehadoop
justinborromeo/incubator-druid
Jan 2019 - Jan 2020
Apache Druid (Incubating) - Column oriented distributed data store ideal for powering interactive applications
Contributions:284 pushes, 57 branches in 11 months
incubatingidealdata-storeapachebig-data
Find and Hire Top DevelopersWe’ve analyzed the programming source code of over 60 million software developers on GitHub and scored them by 50,000 skills. Sign-up on Prog,AI to search for software developers.