Staff Software Engineer (FinTech)

Join Toast, a leading FinTech company, as a Staff Software Engineer on our Payments team. You will be responsible for building our unified payment processing solution, which offers a single, integrated service for payment acceptance across various channels. You will plan, design, build, and deliver features for Toast's payments products, implement best practices, and collaborate with various teams across the company. This role requires 8+ years of experience in designing and implementing robust backend services, proficiency in Kotlin (or Java), and familiarity with PCI-DSS and modern data architectures.

• Plan, design, build, and deliver features for Toast’s payments products, ensuring high-quality standards.
• Collaborate with product management and UX teams on the definition and design of features, and roll out features to customers.
• Lead and mentor junior engineers on best practices in architecture, design, coding, testing, deployment, etc.
• Proven ability to design and develop scalable and secure APIs that integrate with various internal/external systems
• Ability to step into a technical leadership role on the team, guiding/coaching/mentor more junior engineers on best practices in architecture, design, coding, testing, deployment, etc
• Demonstrated experience with microservices architecture and containerization technologies for enhanced scalability and maintainability
• 8+ years of experience in designing and implementing robust backend services
• Applied knowledge of best practices in API lifecycle management, including versioning, documentation, and deprecation strategies, with the ability to share this amongst the team and peers
• Familiarity with AI-augmented development workflows and tools (e.g., Claude Code, GitHub Copilot, Codex, or similar)
• Familiarity with PCI-DSS
• Experience designing payments APIs
• Experience with modern data architectures (event sourcing, OLAP, ETL/ELT, streaming data)
• Proficiency in Kotlin (or Java and willing to learn Kotlin) and Kotlin-specific frameworks and libraries for building efficient backend solutions
• Demonstrated proficiency with DynamoDB or PostgreSQL