Senior Embedded Software Engineer

Since we opened our doors in 2009, the world of commerce has evolved immensely, and so has Square. After enabling anyone to take payments and never miss a sale, we saw sellers stymied by disparate, outmoded products and tools that wouldn’t work together.

So we expanded into software and started building integrated, omnichannel solutions – to help sellers sell online, manage inventory, offer buy now, pay later functionality, book appointments, engage loyal buyers, and hire and pay staff. Across it all, we’ve embedded financial services tools at the point of sale, so merchants can access a business loan and manage their cash flow in one place. Afterpay furthers our goal to provide omnichannel tools that unlock meaningful value and growth, enabling sellers to capture the next generation shopper, increase order sizes, and compete at a larger scale.

Today, we are a partner to sellers of all sizes – large, enterprise-scale businesses with complex operations, sellers just starting, as well as merchants who began selling with Square and have grown larger over time. As our sellers grow, so do our solutions. There is a massive opportunity in front of us. We’re building a significant, meaningful, and lasting business, and we are helping sellers worldwide do the same.

The Role

Foundational to our product offerings is a hardware portfolio that caters to a broad spectrum of sellers and their needs. In this role, you will be responsible for developing the embedded software in Square’s hardware products, contributing to our vision of creating robust and reliable payment devices. This role will report to the firmware engineering manager for our Connected Hardware products.

You will: 

• Architect, develop, and debug embedded software for microcontroller-based devices with real-time operating systems
• Implement and maintain a common firmware platform for all of Square’s hardware products through design, documentation, code review, etc.
• Conduct and support testing, including unit tests, integration tests, and system-level tests
• Optimize code for performance, memory usage, and power efficiency to meet requirements of resource-constrained embedded systems
• Collaborate with application and systems software teams to establish interoperability between embedded systems and higher-level software layers
• Partner with manufacturing, electrical engineering, and other teams to validate hardware-software integration and ensure system reliability
• Build reliable tools to support firmware development, build systems, and product debugging

You have:

• 5+ years of relevant industry experience
• BS in Computer Science, Computer Engineering, Electrical Engineering, or equivalent practical experience
• Proficiency in C / C++ development, with strong skills in embedded tools and debugging techniques
• Experience with microcontroller platforms (e.g. STM32, or similar) and familiarity with peripheral interfaces (I2C, SPI, UART, USB, etc.).
• Understanding of real-time operating systems, such as FreeRTOS, Micrium OS, or Zephyr
• Solid knowledge of embedded debugging techniques and tools (e.g. JTAG, GDB, oscilloscopes, logic analyzers).
• Strong software development practices, including modularization, documentation, and testing methodologies
• Ability to diagnose system-level issues and identify solutions
• Experience shipping consumer electronics products

Even better if you have any of the following:

• Familiarity with wireless communication protocols (e.g. BLE, NFC)
• Proficiency in Python (or similar scripting languages) for automated testing, tooling, etc.
• Excellent written and verbal communication skills for collaboration with cross-functional as well as documentation
• Familiarity with electrical engineering fundamentals, such as reading schematics, understanding PCB layouts, and working with lab equipment