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Signify Technology Logo Signify Technology · IT - Software Development

Principal Python Engineer

United Kingdom, London 135000.00 - 145000.00 GBP / Year · Job Posted June 29, 2026
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Job Description

Principal Python Engineer, London, Europe's Largest Equities Exchange. We are working exclusively with one of the world's largest exchange operators on a Principal Python Engineer hire in London. This is a senior individual contributor role within a small, highly skilled engineering team building and expanding the data pipeline and event streaming infrastructure that powers the largest equities exchange in Europe. The Role - You will lead complex engineering projects end to end, working closely with business development and sales teams to deliver new products and features, and mentoring engineers across Europe and the US. The team takes software craftsmanship seriously — testable, maintainable code, pair programming and TDD are core to how they work.

Job Responsibility

  • Lead complex engineering projects end to end
  • Work closely with business development and sales teams to deliver new products and features
  • Mentor engineers across Europe and the US

Requirements

  • Expert Python
  • advanced SQL
  • deep Linux knowledge
  • PostgreSQL
  • Snowflake
  • Apache Kafka
  • Apache Airflow
  • Django, Flask or FastAPI
  • TDD
  • BDD
  • pair programming
  • Java familiarity a plus

Nice to have

  • Degree in Computer Science or related field preferred
  • Financial markets experience a strong plus — market data, order management, algorithmic trading or financial systems integration

What we offer

  • Competitive salary and incentive compensation
  • Private medical including dental
  • private GP service
  • life insurance
  • 7% pension contribution, no employee contribution required
  • 25 days holiday rising to 30
  • complimentary lunch daily
  • 4 days in office, London
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