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. A day in the life (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 What you'll need to thrive (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 Special Sauce (*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) #LI-HYBRID #BI-Hybrid AI at Toast At Toast, one of our company values is that we're hungry to build and learn. We believe learning new AI tools empowers us to build for our customers faster, more independently, and with higher quality. We provide these tools across all disciplines, from Engineering and Product to Sales and Support, and are inspired by how our Toasters are already driving real value with them. The people who thrive here are those who embrace changes that let us build more for our customers; it’s a core part of our culture. Our Total Rewards Philosophy We strive to provide competitive compensation and benefits programs that help to attract, retain, and motivate the best and brightest people in our industry. Our total rewards package goes beyond great earnings potential and provides the means to a healthy lifestyle with the flexibility to meet Toasters’ changing needs. Learn more about our benefits at https://careers.toasttab.com/toast-benefits . How Toast Uses AI in its Hiring Process Throughout the hiring process, our goal is to get to know you. We use AI tools to support our recruiters and interviewers with tasks like note-taking, summarization, and documentation of interviews to ensure they can be fully focused on your conversation. All hiring decisions are made by people. To learn more: https://careers.toasttab.com/ai-in-hiring Our Approach to Hybrid Working We embrace a hybrid work model that fosters in-person collab