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Koinly

Cryptocurrency Tax Solution. Generate tax reports for your crypto trading and related activity automatically.

Staff Software Engineer

Full-stack EngineerSoftware EngineerFull TimeRemoteLeadTeam 11-50Since 2019H1B No SponsorCompany SiteLinkedIn

Location

United Kingdom

Posted

71 days ago

Salary

$100K - $115K / year

Seniority

Lead

Bachelor Degree8 yrs expEnglishPostgreSQLRubyRuby on Rails

Job Description

Staff Software Engineer

Koinly

• Engineer and optimize high-performance Ruby systems that handle billions of financial transactions, solving deep scaling, data, and code-quality challenges. • Design and develop scalable backend systems that process billions of financial transactions. • Provide technical direction across projects and collaborate with product and engineering leads to define priorities and architecture. • Own project delivery: from design and implementation to performance and reliability in production. • Refactor and modernize core Ruby systems to improve maintainability, readability, and speed. • Mentor other engineers through technical reviews, design discussions, and clear documentation.

Job Requirements

  • 8+ years of backend experience with Ruby on Rails at scale
  • Proven record improving system performance and code quality
  • Strong understanding of data flows and software design principles
  • Experience working cross-functionally in async, remote environments
  • Clear communication and ownership mindset.
  • Bonus: Experience tuning Postgres in production
  • Built or optimized data ingestion or reconciliation pipelines
  • Open-source contributions to Ruby, Rails, or performance tooling
  • Background in fintech, taxtech, open banking, or blockchain systems

Benefits

  • 32 days of PTO
  • Async culture
  • Flexible work-schedule
  • A culture of high autonomy and ownership

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