Principal Software Engineer

Toast is driven by building the restaurant platform that helps restaurants adapt, take control, and get back to what they do best: building the businesses they love.

Toast is empowering restaurants to build better businesses. We’re a rapidly growing company that’s revolutionizing the restaurant industry by providing a comprehensive, cloud-based platform that combines point of sale, guest engagement, operations, and team management on a single Android tablet. We’re passionate about helping restaurants succeed.

About the team:

The Card Readers team is at the heart of Toast's payment processing capabilities. We develop and maintain seamless integrations with leading card reader vendors, ensuring reliable and secure payment experiences for our restaurant customers. You'll be working on core components of the Toast platform, impacting thousands of businesses daily.

Bready* to make a change?

As a Principal Engineer on the Card Readers team, you will be a technical leader responsible for designing, developing, and maintaining our POS payment integrations. You will work closely with hardware SDKs, the core POS application team, and other cross-functional stakeholders to drive technical decisions and define the target architecture for our payment solutions. Your expertise in high-throughput asynchronous JVM solutions, coupled with a deep understanding of mission-critical transactional processing, will be crucial in delivering robust and scalable solutions.

About this roll*: (Responsibilities)

• Architect, design, and develop robust, high-performance applications using Kotlin.
• Lead technical discussions and decisions on best practices, performance optimizations, and security.
• Collaborate with cross-functional teams (backend, product, UX/UI, QA) to deliver seamless payment experiences.
• Optimize mobile payment flows for security, speed, and reliability.
• Shape the face of development at Toast by helping to balance building maintainable software for long term success, with the need to deliver value to customers in an iterative fashion.
• Ensure compliance with PCI-DSS, security best practices, and other financial industry standards.
• Mentor and guide junior engineers, conduct code reviews, and drive best practices
• Troubleshoot and resolve complex technical issues, ensuring high availability and performance.
• Stay up to date with emerging technologies, frameworks, and trends.
• Leverage cutting edge AI tools to enhance your development workflow, improve velocity, and help pioneer new approaches to building - contributing to a culture of innovation and productivity across the team.

Do you have the right ingredients*? (Requirements)

• Expert-level proficiency in Kotlin, Java, and/or JVM languages
• High scale successes with multi-threading/concurrency (deep experience with coroutines a plus)

• Experience working in a large project/codebase, architecting for clear domain boundaries, modularity, reusability, and testability
• Track record of complex and robust SDK integrations completed successfully
• Experience designing public APIs for hassle-free consumption
• Expertise in observability, monitoring, and alerting for complex user-device interactions
• Strong skills in mentoring a team of developers on best practices
• Openness and enthusiasm for AI tooling to enhance R&D productivity
• Excellent communication, collaboration, and problem-solving skills that lead others by example

AI at ToastAt Toast 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 Spread* of Total RewardsWe 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 athttps://careers.toasttab.com/toast-benefits.

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