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Cryptocurrency Tax Solution. Generate tax reports for your crypto trading and related activity automatically.
Staff Software Engineer
Location
United Kingdom
Posted
71 days ago
Salary
$100K - $115K / year
Seniority
Lead
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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