Apr. 2024 - Now   Software Engineer, Rothesay, London: StratOS team

• Responsibilities: improve tooling for quants designing models and migrate systems away from Goldman Sachs proprietary systems
• Multiple improvements to drive down the CI build time and improve the success rate
• Wrote scripts to pin down external package versions in Conda environments
• Improvements to Cloud-based Linux containers used as development environments (Gitpod)
• Engineering support for end of day risk calculation

✓   Python, Conda, Rust, AWS, SecDB, Gitpod

Jun. 2022 - Feb. 2024   Software Engineer L4, Paxos, London: Brokerage team

• Responsibilities: design and delivery of a smart order routing system from the ground up, adapting to the quickly evolving requirements of crypto markets
• Designed the smart order router in a team of three using Go and Rust micro-services
• Wrote a connector service to internal and external market-places for order execution
• Drove performance improvements by:
  • Load-testing a production-like system while analyzing metrics and resource usage of the key components
  • Using results to tune SQL indices, RabbitMQ parameters and calls to accounting services developed by other teams
• Lead cross-team initiatives to spread Rust knowledge and best practices — in particular to catch logical errors at compile time by leveraging the type system
• Engineering support for customer-facing trading-systems, from REST & FIX APIs to the order-matching engine

✓   Rust, Go, Python, AWS, Postgres, Microservices, Protocol Buffer, RabbitMQ

Sep. 2020 - Jun. 2022   Software Engineer, Cloudflare, London: Distributed Denial of Service (DDoS) protection team

• Responsibilities: maintain and improve automated mitigation systems against DoS attacks, answer customer queries

• Redesigned with a colleague the data pipeline to display network analytics to customers. It involved mainly data extraction using eBPF, efficient and performant storage in ClickHouse and a public facing GraphQL API
• Extended and automated data extraction for public reports like “Network-layer DDoS attack trends for Q4 2020”
• Optimized directly-written eBPF assembly, C code, ClickHouse tables and materialized views
• Troubleshooted, fixed bugs and extended the Gatebot Python codebase
• Co-authored the blog post “How we built Network Analytics v2”

✓   C, eBPF, XDP, Rust, Go, Python, Docker, TCP, UDP, dos attacks, ClickHouse, GraphQL

2017 - 2020   Télécom Nancy, Nancy, France: Masters of Science in Computer Science

Focused on software engineering and project management

2015 - 2017   Lycée A. Fournier, Bourges, France: two-year course equiv. to a BSc in Mathematics and Physics

Preparation for the highly competitive nationwide entrance exams for French Grandes Écoles

2018 - 2019   Full compiler: Tiger language (team of 4 people, 6 months)

• Wrote a grammar for the language with ANTLR, constructed the abstract syntax tree (AST)
• Did semantic analysis on the AST, generated assembly code (function, loops, conditional branches)

✓   Java, ANTLR, formal language theory

2019 - 2024   Rusqlite Migration: database schema migration library for rusqlite, written with performance in mind

• Reviewed contributions, feature requests and bug reports. Respected semantic versioning strictly
• Used in the NordVPN Linux client, Tabby (self-hosted AI coding assistant)…

✓   Rust (noteworthy package used: lazy_static, rusqlite), SQLite

2019 - 2024   Plugins for the neovim text editor: hundreds of daily users (based on GitHub clones and stars)

✓   Lua, Fennel (a Lisp dialect), VimScript, neovim APIs

2014 - Now   Misc. Open-Source Contributions: please visit my website at joly.pw/open-source for a full list