• Designing, building, and evolving public APIs used by external developers and partners • Improving the security, consistency, and usability of Smile’s API surface • Building and maintaining Ruby on Rails services that power integrations and developer tooling • Developing and evolving Smile’s JavaScript SDKs and frontend libraries • Crafting thoughtful developer experiences — from API ergonomics to documentation • Iterating on existing and building new in-house integrations • Partnering with internal teams to help solve for novel merchant use cases • Championing technical discussions, decisions, and trade-offs • Identifying opportunities to raise the bar in areas like architecture, performance, and security • Sharing context, feedback, and knowledge within and across teams

• Design, develop and maintain backend components using Java and Python • Work on Spring / Spring Boot based services and knowledge of Webservices (REST / SOAP) • Debug complex production issues and perform root cause analysis • Troubleshoot performance and support high priority production issues • Work with QA team for testing, verification and defect closure • Work with Support team to analyze live customer/production issues and drive resolution • Participate in Agile/Scrum ceremonies and deliver tasks in sprint cycles

• Deliver production quality software in your core stack (backend, frontend, data, cloud or security) • Design, build and maintain services and APIs, or user facing applications, depending on your role • Work with modern engineering practices: clean code, code reviews, testing and CI/CD • Collaborate in remote teams with clear communication, proactive ownership and reliable delivery • Support incident fixes and continuous improvements when needed, depending on the project • Contribute to agile delivery, usually Scrum or Kanban (daily syncs, planning, reviews, retros)

• Lead technical direction for backend systems, making architectural decisions and setting engineering standards. • Build high-performance, low-latency trading systems using Rust. • Maintain the order matching engine with microsecond-level latency requirements. • Build and maintain risk management systems including margin calculations, position tracking, and automated liquidations. • Design database schemas and queries optimized for high-throughput financial data using PostgreSQL. • Architect systems for global scale with high availability and fault tolerance. • Mentor and guide other engineers through code review, pairing, and technical decision-making. • Collaborate with front-end developers to design trading APIs and support their integration work. • Implement security-critical systems for handling user funds and sensitive financial data. • Write and maintain automated tests including unit, integration, and load tests. • Stay current with DeFi protocols and emerging exchange architectures.