Résumé · Clément Joly – Open-Source, Rust & SQLite

Detail-oriented and self-motivated Software Engineer based in London.
Proficient in particular in Rust and Python.

Employment

Responsibilities: create Cloud-based systems to replace Goldman Sachs (GS) proprietary systems, develop tools for quants
Developed a distributed compute system on AWS from the ground up, replacing a GS system.
- Considered off-the-shelf solutions using e.g. Slurm, AWS Batch/ECS. They did not meet stringent security and confidentiality requirements (e.g. authentication, PII) as well as latency (<100ms to start tasks) and throughput (peaks of 10k+ jobs submitted per second) requirements. As a result, we went for a semi-custom solution
- Integrated into existing UIs and took into account feedback from users (quants)
Wrote scripts to pin down external package versions across multiple Conda environments, to ensure consistency
Configured Cloud-based, ephemeral Linux containers as development environments (Gitpod/Ona with PyCharm).
- Delivered a “battery-included” experience for the main quants workflows, working with the infrastructure team to pre-install on the corporate fleet
Regularly worked to improve CI pipelines success rate and build time (e.g. with smart, minimal dependencies)
Engineering support for end of day risk calculation and business hours CI pipelines

✓ Python, Conda, Rust, AWS (EC2, MemoryDB, CloudWatch), SecDB, Gitpod/Ona, TeamCity

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

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

Focused on software engineering and project management
School projects: full compiler, film recommendation system, embedded platform to acquire sensor data

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

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

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