Benoit Lacelle
VPE & Co-Founder at Solven
Paris, Ile-de-France, Réunion
Summary
🤩
Rockstar🎓
Top SchoolBenoit Lacelle is a Paris-based VPE and co-founder with 12+ years delivering high-performance Java In-Memory solutions for BI and Big Data across startups and enterprises. He moved from deep R&D experience on ActivePivot to broad in-memory work spanning Spark, Gigaspaces and Indexima, routinely running JVMs with up to tens of terabytes of data. As a freelance expert and founder of Solven, he combines hands-on bug-hunting and performance tuning with architecture, security and scalability leadership for production-critical platforms like M-iTrust. His open-source contributions include extending RoaringBitmap for long values and improving Java tooling (Spotless, JavaParser), demonstrating attention to low-level correctness and developer ergonomics. Clients value his ability to deliver seemingly impossible features or fixes quickly while leaving teams more capable than he found them. He prefers simple, pressure-tested code and can onboard into high-stakes projects with minimal ramp-up.
12 years of coding experience
10 years of employment as a software developer
Lycée LakanalMaster's degree Computer Science, Master's degree Computer Science at Université Paris CitéEngineer's degree Mathematics and Computer Science, Engineer's degree Mathematics and Computer Science at Ecole nationale des Ponts et Chaussées
French
Github Skills (21)
parserator10
json10
bitmap10
parser10
abstract-syntax-tree10
formatting10
data-serialization10
text-formatting10
roarr10
java10
serialization10
javas10
jackson10
yaml10
bitmaps10
Programming languages (16)
Github contributions (5)
RoaringBitmap/RoaringBitmap
Aug 2017 - Nov 2022
A better compressed bitset in Java: used by Apache Spark, Netflix Atlas, Apache Pinot, Tablesaw, and many others
Role in this project:
Back-end Developer
Back-end DeveloperContributions:86 reviews, 87 commits, 24 PRs in 5 years 4 months
Contributions summary:Benoit's primary contribution was introducing a new `RoaringTreeMap` class to handle bitmaps holding long values. They implemented core functionalities such as adding long values, calculating cardinality, selecting values, iterating through the values, ranking, and serializing the class. The user also added several test cases to validate the correctness of the new implementation, ensuring it functioned correctly with empty sets, single values, and various ranges of values.
bigdataroaring-bitmapsspark-mlroaringbitmapdruid
diffplug/spotless
Jan 2023 - Jan 2023
Keep your code spotless
Role in this project:Full-stack Developer
Full-stack DeveloperContributions:37 reviews, 39 commits, 29 PRs in 15 days
Contributions summary:Benoit primarily focused on the implementation and maintenance of YAML and JSON formatters within the `spotless` project. Their contributions include adding and refactoring code related to Jackson-based YAML and JSON formatting, and integrating these new features into the Maven plugin. They also addressed style issues, fixed tests, and implemented features related to the configuration of Jackson features and integration with Gradle.
spotlessgradleformatterprettiersass
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