Senior Software Engineer- Fintech

Toast creates technology to help restaurants and local businesses succeed in a digital world, helping business owners operate, increase sales, engage customers, and keep employees happy. Fintech at Toast operates one of the most critical portions of the Toast infrastructure: processing payments on behalf of our restaurants and ensuring that restaurants are paid in a timely manner. Payment processing is a key source of Toast’s revenue and also the lifeblood of our customers; we process millions of dollars in transactions per day. We are seeking a Senior Software Engineer to join our Payments team to build out our unified payment processing solution. This platform offers a single, integrated service for payment acceptance across various channels and supports a configurable enterprise approach. It is designed to allow a build-once, available-to-all strategy for both existing and emerging payment methods. The successful candidate will contribute to the development of services providing supporting and core functionality within and around this payment processing solution. Responsibilities Design, build, and deliver features for Toast’s payments products Develop and implement automated test suite to ensure the code shipped to our customers meets the highest quality standards Roll* features out to customers, including monitoring for success Collaborate with our PM (and UX) on the definition and design of features Partner with a wide array of teams across Toast Work with experienced engineers to deliver design and code review Requirements 5+ years of experience in designing and implementing robust backend services Proven ability to develop scalable and secure APIs that integrate with various internal/external systems Knowledge of best practices in API lifecycle management, including versioning, documentation, and deprecation strategies Demonstrated experience with microservices architecture and containerization technologies for enhanced scalability and maintainability Nice to Haves Demonstrated proficiency with DynamoDB or PostgreSQL Proficiency in Kotlin (or Java and willing to learn Kotlin) and Kotlin-specific frameworks and libraries for building efficient backend solutions Experience with modern data architectures (event sourcing, OLAP, ETL/ELT, streaming data) Experience designing payments APIs Familiarity with PCI-DSS Familiarity with AI-augmented development workflows and tools (e.g., Claude Code, GitHub Copilot, Codex, or similar) For roles in the United States, it is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability. #J-18808-Ljbffr Toast