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Core Developer (Python) - Selby Jennings

Selby JenningsLondon🇬🇧United KingdomPosted 21 Sept 2026

Quick Overview

Seniority
Mid Senior
Employment type
Full Time
Work mode
Hybrid
Location
London, United Kingdom
Posted
12 hours ago
SQLC++PostgreSQLPython

Job Description


Key Responsibilities

  • Design, build and maintain business-critical trading infrastructure and backend services.
  • Develop systems across trade capture, position management, reconciliation and settlement workflows.
  • Build scalable data platforms to support trading, risk and operational processes.
  • Create internal tooling used by traders, quantitative researchers and operations teams.
  • Improve the performance, reliability and scalability of existing systems.
  • Collaborate closely with stakeholders across engineering, trading, quantitative research and operations.
  • Take ownership of projects from design through to production deployment and support.
  • Contribute to architectural decisions and engineering best practices across the platform.
  • Troubleshoot complex production issues and continuously improve system resilience.

Key Requirements
  • Strong commercial experience developing software in Python.
  • Experience within trading, market making, electronic trading or financial markets technology.
  • Strong knowledge of Linux environments and operating systems.
  • Solid SQL and PostgreSQL experience.
  • Experience building and operating production-grade backend systems.
  • Exposure to market data, execution systems, position management, reconciliation or settlement platforms.
  • Knowledge of C++ or other performance-oriented languages.
  • Strong understanding of software engineering fundamentals, design patterns and system architecture.
  • Experience working with distributed systems, messaging platforms or event-driven architectures.
  • Excellent problem-solving skills and ability to work independently.
  • Comfortable working directly with technical and non-technical stakeholders.

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