Senior Python Backend Engineer (Performance \& Parallel Execution)
Location:
Remote (ANZ time zones preferred)
Term:
Full-time, equity
Company Description
Themelia is building the indexing layer of crypto. We're now entering a performance and scaling phase and are seeking a senior Python engineer with expertise in computational optimisation and concurrent systems to improve index calculation performance and parallelise exchange trade execution paths. You’ll optimise bottlenecks in Pandas/Polars pipelines, compile numeric workloads with Numba or Cython, and manage multi-exchange execution flows efficiently using async or multiprocessing patterns.
Responsibilities
Profile and optimise CPU-intensive analytical functions using Numba, Cython, or Polars
Parallelise and coordinate trade execution logic across multiple exchanges
Maintain concurrency-safe integrations with exchange APIs (async I/O, multiprocessing, or queues)
Refactor and benchmark Pandas-based data pipelines for speed and reliability
Collaborate with the Postgresql engineer to streamline database-to-API data flow
Log, monitor, and validate performance improvements in production
Requirements
Advanced Python (5+ years) with focus on performance and concurrency
Strong experience with Numba, Cython, or other compiled-code acceleration
Proficiency in asyncio, concurrent.futures, or multiprocessing
Solid understanding of Pandas internals and familiarity with Polars or DuckDB
Comfort with Postgresql, SQLAlchemy, and structured logging
Strong mathematical and analytical reasoning
Nice to Have
Experience with crypto or traditional exchange APIs (REST/WebSocket)
Familiarity with message queues (Redis, RabbitMQ, Kafka)
Background in quantitative or financial data systems
Compensation
Equity based
How to Apply
Send a short note, your LinkedIn and GitHub profile to jessica@themelia.co