BlueWalker Capital is a proprietary trading firm developing systematic and quantitative trading strategies native to prediction markets. It's still early days for us—we are deepening a moat across trading infrastructure, datasets, and modeling. Our mission is to become the leading hedge fund in this emerging asset class, delivering investment returns while making prediction markets efficient as the world's most accurate source of truth.

Daniel

Howard is the Founder and Managing Partner of Halo Capital, a digital assets venture fund associated with Brevan Howard. Previously, he was a Principal at 10T Holdings, a Machine Learning Engineer at Spark Cognition, and a Data Scientist at Verisk. Daniel also spent over seven years in academia across Columbia University's Engineering and Business schools.

Wouter also seeded a startup hedge fund that was acquired by integral market maker IMC Trading in 2023. We are a small engineering team, which means your responsibilities scale rapidly and your impact is clear and foundational.

You would own the execution path end to end: order submission, fill handling, position tracking, reconciliation, and the risk controls around them. Python covers services where iteration speed matters most; Rust covers latency-critical and concurrency-heavy components.

Build and maintain risk controls: exposure limits, drawdown monitoring, kill switches, and their alerting. Make forward-looking architectural decisions, balancing risk, performance, cost, and maintainability. Stress-test and strengthen critical systems for robustness and clarity. 2+ years of hands-on production experience in Python, including asyncio, WebSocket clients, and event-loop behaviour under sustained load. ~ Production experience in Rust,



with demonstrated work.

Async Rust: Tokio, Send/Sync bounds, cancellation safety, and the effect of blocking work on an async runtime. ~ Experience with systems where state correctness is a primary requirement: idempotency, retry semantics, and reconciliation against an external source of truth. ~ Relational databases and in-memory stores (Postgres, Redis, or equivalent): schema design, indexing, and transactional boundaries. ~ Working knowledge of OpSec practices, secrets management, in both personal workstation and production environments. ~ Docker and Docker Compose, and the DevOps needed to provision servers, run and supervise long-lived services, configure networking, and work in Linux. ~ Ability to design and write production-grade systems without LLMs, while being proficient and deeply integrated with AI tools to maximize development velocity. ~ A background in statistics, computer science, mathematics, physics, or other quantitative fields.

Market microstructure: order books, fee structures, slippage, and execution quality measurement. Performance measurement with flamegraphs, perf, criterion, and latency histograms, reported at p99 and p99.Property-based and deterministic testing of concurrent code: proptest, loom, fuzzing, or replay against recorded feeds. Rust–Python interop via PyO3 or FFI.

What it's like here ~ Project ownership and autonomy, flat company structure. ~ Company culture is informal, non-hierarchical, ambitious, collaborative and entrepreneurial.

Flexible

Holidays ~ Spain produces world-class technical talent, but the local market rarely provides the opportunities to unlock exponential careers. Join us as we expand our footprint across global capital markets and put Spain on the map of excellence.

📌 Systems Engineering Engineer (Cataluña)
🏢 BlueWalker Capital
📍 Cataluña