Ben Sless
Software Engineer at 44 Quad
Israel
Summary
🤩
Rockstar🎓
Top SchoolBen Sless is a software engineer with nine years of experience building high-performance, large-scale systems and a strong background in functional programming and low-level optimization. He progressed from IC and integration engineering at Intel to software roles at Apple and AppsFlyer, reaching Staff Engineer before joining 44 Quad, blending hardware-aware rigor with distributed systems design. An active contributor to prominent Clojure projects like Datascript and Malli, Ben has driven measurable performance gains through comparator inlining, lazy tuple collection, and validator optimizations. He favors data-driven, functional approaches (and has a soft spot for Lisp), which shows in both his open-source work and production engineering. Avid reader and lifelong learner, he pairs deep technical curiosity with practical tooling improvements and a habit of surfacing efficient, well-tested solutions. Based in Israel, he brings a rare combination of VLSI discipline and large-scale software craftsmanship to backend and data-focused engineering challenges.
9 years of coding experience
10 years of employment as a software developer
Bachelor of Science (B.Sc.) Electrical and Electronics Engineering, Bachelor of Science (B.Sc.) Electrical and Electronics Engineering at Technion - Israel Institute of Technology
Hebrew, English
Github Skills (21)
algorithm10
algorithms10
immutables10
schema-validation10
clojure-cli10
databases10
query-optimization10
data-structure10
clojure10
data-transformation10
performance-optimization10
data-structures10
functional-programming10
datastructures-algorithms10
immutability10
Programming languages (10)
Github contributions (5)
metosin/malli
May 2021 - Jan 2023
High-performance data-driven data specification library for Clojure/Script.
Role in this project:
Back-end Developer
Back-end DeveloperContributions:18 reviews, 47 commits, 30 PRs in 1 year 7 months
Contributions summary:Ben primarily contributed to the `malli` library's core functionality, focusing on validation, schema definition, and transformation logic. They refactored and optimized code related to validators, iterators, and map-based schemas, improving performance. The user's work involved significant changes to internal utility functions and the addition of tests to ensure the correct behavior of the implemented components. They also added support for time-based schemas.
transformationdata-drivenvalidationgeneratorsclojurescript
tonsky/datascript
Aug 2022 - Oct 2022
Immutable database and Datalog query engine for Clojure, ClojureScript and JS
Role in this project:Back-end Developer
Back-end DeveloperContributions:23 commits, 2 PRs, 2 comments in 1 month
Contributions summary:Ben primarily focused on optimizing the `datascript` database and query engine, contributing significantly to performance improvements. Their work involved inlining comparators and function calls within the Clojure code, indicating a focus on low-level performance optimization. They also implemented specialized comparators and optimized join-tuples, demonstrating a deep understanding of the system's internal workings and a commitment to efficient data handling. Further contributions included fully lazy tuple collection and improvements to getter functions, contributing to overall performance and resource efficiency.
queryimmutable-databasequery-enginedeclarative-programmingdatascript
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