Costin Leau
Distinguished Engineer at Elasticsearch
San Francisco, California, United States
Summary
🤩
Rockstar🎓
Top SchoolCostin Leau is a Distinguished Engineer with 13+ years building query languages and analytical engines, currently leading development of Elasticsearch Query Language and having created Elasticsearch SQL and EQL from the ground up. Based in San Francisco, he blends deep distributed-systems expertise with practical product delivery, shipping core back-end features for the widely used elastic/elasticsearch and elastic/elasticsearch-hadoop projects. A frequent conference speaker, he has guided integrations across Hadoop, Spark and NoSQL ecosystems and earned an Outstanding Contribution Award for his impact. Notably, his work spans the full query stack—parser through JDBC driver and execution engine—revealing both low-level mastery and a knack for turning research-grade ideas into production-grade systems.
13 years of coding experience
13 years of employment as a software developer
"Cantemir Voda" National CollegeScoala generala 52Scoala generala 5POLITEHNICA București National University for Science and Technology
Stackoverflow
26reputation
2kreached
1answer
0questions
Github Skills (20)
spark-sql10
amazon-elasticsearch10
hadoop10
java10
javas10
elasticsearchquery10
aws-elasticsearch10
elasticsearch10
elasticsearch-api10
json-parser9
json9
query-optimization9
jsonp9
parsing9
rest-api9
Programming languages (9)
Github contributions (5)
elastic/elasticsearch-hadoop
Mar 2013 - Aug 2016
:elephant: Elasticsearch real-time search and analytics natively integrated with Hadoop
Role in this project:
Back-end Developer
Back-end DeveloperContributions:1669 commits, 53 PRs, 477 pushes in 3 years 5 months
Contributions summary:Costin's contributions primarily focused on enhancing the Elasticsearch Hadoop integration with functionality for ES 1.0 and 2.0 as well as integration with Spark SQL. The user added support for features such as filtering, automatic index creation, the ability to write data into different ES indices and also implemented support for a raw JSON format. The user also improved performance through enhancements to index name, mapping, and value extractions.
analyticsintegratedelephantelasticsearchhadoop
elastic/elasticsearch
Sep 2013 - Dec 2022
Free and Open Source, Distributed, RESTful Search Engine
Role in this project:Back-end Developer
Back-end DeveloperContributions:1535 reviews, 920 commits, 756 PRs in 9 years 4 months
Contributions summary:Costin primarily contributed to the back-end functionality of the Elasticsearch project, specifically focusing on the EQL (Event Query Language) module. Their work involved refactoring SQL processors, improving the handling of edge cases in result sets and indices. They implemented new functionalities related to filtering and data handling to improve the query engine. Their contributions demonstrated a strong understanding of database query processing and internal code structure of the ESQL engine.
restfulsearch-engineopensearchelasticsearchjava
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