Senior Software Engineer - Android

Senior Software Engineer - Card Readers

Toast is building the all-in-one restaurant platform that helps restaurants operate their business, increase sales, engage guests, and keep employees happy. Toast connects employees, operations, and guests on a reliable, easy-to-use platform so restaurateurs can stay one step ahead of a rapidly evolving hospitality market.

The Card Readers team processes millions of card payments a day for Toast’s restaurant customers. Hundreds of thousands of restaurants depend on the software we build to run their business. We make payments friction-free while maintaining  the highest levels of security, enabling new payment options, and staying at the forefront of emerging technologies.

As a Senior Software Engineer on the Card Readers team, it’s your job to make sure those millions of payments are processed quickly, reliably, and securely. You will be a key team member 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 refine the target architecture for our payment solutions. Your expertise in high-throughput asynchronous JVM solutions, coupled with a deep understanding of mission-critical transaction processing, will be crucial in delivering robust and scalable solutions.

About this roll*: (Responsibilities)

• Design, develop and roll out 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 in software development.
• Troubleshoot and resolve complex technical issues, ensuring high availability and performance.
• Participate in agile development processes, including sprint planning, daily stand-ups, and retrospectives.
• Stay up to date with emerging technologies, frameworks, and trends.
  
  

Do you have the right ingredients*? (Requirements)

• Expert-level proficiency in Kotlin, Java, and/or JVM languages

Deep knowledge of multi-threading/concurrency (experience with coroutines a plus)

• Experience working in a large (Android) 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 fellow 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

Nice to have

• Card Payments/EMV experience
• Hardware/device integration experience
• Security and key management experience

What they're looking for

Do you have the right ingredients*? (Requirements)

• Strong proficiency in Kotlin and modern Android frameworks (Jetpack, Coroutines, Flow).
• Deep understanding of Android architecture components, MVVM, and Clean Architecture.
• Strong knowledge of Android security best practices and secure data storage.
• Familiarity with mobile payment processing, tokenization, NFC, and EMV standards (a plus).
• Experience working with third-party payment gateways, in-app purchases, or POS integrations (a plus).
• Excellent communication and collaboration skills, with the ability to work effectively with cross-functional teams.
• Strong problem-solving skills and ability to work in a fast-paced, agile environment.

Special Sauce: (non-essential skills, nice to have)

• Prior experience with distributed systems and microservices
• Experience with EMV Payments or Kernel

A day in the life (Responsibilities)

[TA PARTNERS - PLEASE DELETE THE NON-APPLICABLE BULLET BELOW BEFORE ADDING YOUR JOB REQUIREMENTS] 

For Engineering Managers:
Champion the use of AI tools and practices to accelerate development, improve team velocity, and pioneer new ways of building - setting the bar for what it means to be an AI-first engineering organization.

For Engineering ICs:
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.

What you'll need to thrive (Requirements)

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.