Senior Software Engineer, Square Financial Services

Block; San Francisco (CA); On-site; USD 120,000 - 160,000; Full time

Job summary

Block is seeking a Senior Software Engineer for their SFS Bank Platform team in San Francisco. This role requires 6+ years of software development experience, with a strong focus on building robust financial systems and features.

You will lead impactful designs and work collaboratively across teams to enhance the banking platform, ensuring compliance and security. The ideal candidate will be proficient in Kotlin and AWS, and have experience with AI tools.

Qualifications

• 6+ years of software development or equivalent experience.
• 1+ years leading large scale features with timely project delivery.
• Experience in building financial infrastructure systems.

Responsibilities

• Design and develop features for the banking platform.
• Collaborate with other teams to onboard their products.
• Ensure security and compliance in data handling.
• Lead technical design and execution of large-scale features.

Skills

Software Development

Team Leadership

AWS

Kotlin

APIs Development

Customer Empathy

AI Tools Experience

Tools

Temporal.io

Kubernetes

DynamoDB

Kafka

React

Job description

Block is one company built from many blocks, all united by the same purpose of economic empowerment. The blocks that form our foundational teams — People, Finance, Counsel, Hardware, Information Security, Platform Infrastructure Engineering, and more — provide support and guidance at the corporate level. They work across business groups and around the globe, spanning time zones and disciplines to develop inclusive People policies, forecast finances, give legal counsel, safeguard systems, nurture new initiatives, and more. Every challenge creates possibilities, and we need different perspectives to see them all. Bring yours to Block.

The Role

Square Financial Services, Inc ("SFS") is Block's bank. The SFS Bank Platform team makes it easy to safely manage, move, reconcile, and understand all of the funds at SFS and with integrated Block products. We build the core system-of-record ledger for the bank, gateways to bank payment networks, and automations for the finance, treasury, and accounting teams. We're building a foundation to support more of Block's products. Come help us build a better bank!

As a Senior Software Engineer on the SFS Bank Platform team, you will lead the technical design, execution, and delivery of new banking primitives through close collaboration across teams and disciplines. In addition, you'll drive architectural decisions and infrastructure improvements to make our systems more robust and scalable. The things that you build will create significant impact at scale and will fundamentally change the consumer banking landscape as we know it today.

You Will

• Design and build new features into our banking platform that meet the diverse needs of Block's broad portfolio of products and services
• Partner with engineering teams across Block to help onboard their products to SFS
• Build systems that operate on our customers' most sensitive data, while holding Square to the highest standards for security and compliance.
• Prioritize correctness and fault-tolerance in your designs so the team can move fast and innovate without putting our customers at risk.
• Utilize AI tools and an AI-first mindset to accelerate development, improve efficiency, and streamline the engineering lifecycle.
• Ensure the continued operation of our critical services, remediate any problems that occur, and design durable fixes so that they don't happen again
• Lead the technical design, execution, and delivery of large-scale features
• Mentor teammates to elevate engineering standards and foster a culture of technical excellence.

You Have

• 6+ years of software development or equivalent experience
• 1+ years of experience leading large scale features, which includes planning, managing and executing on the delivery projects in a timely manner while maintaining a high quality bar
• Hands‑on skills building software products or services in the cloud
• A track record of building software that is easy to observe and operate
• A strong sense of customer empathy and a drive to ship software that improves their lives
• Excellent written and verbal communication skills. This is a remote‑forward team.
• Experience leveraging AI tools and frameworks to improve developer productivity, code quality, and system efficiency.
• Background in developing financial infrastructure, particularly ledgers or systems‑of‑record requiring high consistency and correctness
• Proficiency building products and services using AWS
• Proficiency with Kotlin
• Experience building public APIs

Technologies We Use and Teach

• Kotlin/Java, Go
• Temporal.io, Kubernetes, AWS Fargate + ECS
• AWS Aurora and DynamoDB
• Kafka, events, microservices
• Internal and industrywide AI enabling/powering tools
• Protocol Buffers, gRPC, HTTP, OpenAPI, TypeScript, React
• Unit Tests, Continuous Integration, and other methods of quality assurance

Block is an equal opportunity employer evaluating all employees and job applicants without regard to identity or any legally protected class. We will consider qualified applicants with arrest or conviction records for employment in accordance with state and local laws and “fair chance” ordinances.

We believe in being fair, and are committed to an inclusive interview experience, including providing reasonable accommodations to disabled applicants throughout the recruitment process. We encourage applicants to share any needed accommodations with their recruiter, who will treat these requests as confidentially as possible.