Sr. Software Engineer

About EarnIn As one of the first pioneers of earned wage access, our passion at EarnIn is building products that deliver real-time financial flexibility for those with the unique needs of living paycheck to paycheck. Our community members access their earnings as they earn them, with options to spend, save, and grow their money without mandatory fees, interest rates, or credit checks. We’re fortunate to have an incredibly experienced leadership team, combined with world-class funding partners like A16Z, Matrix Partners, DST, Ribbit Capital, and a very healthy core business with a tremendous runway. We’re growing fast and are excited to continue bringing world-class talent onboard to help shape the next chapter of our growth journey. POSITION SUMMARY We are looking for an experienced, passionate, and resourceful senior-level engineer with a proven track record to join the EarnIn payroll services team. In this role, you will participate in the design, development, and implementation of frontend and backend services that support the full suite of EarnIn Payroll’s products including our integration platform and payroll SaaS product. Your work will ensure backend systems and user-facing applications are well-aligned, intuitive, and reliable for payroll customers. Come make a difference with us and have fun doing it! This position is hybrid from our Mexico City office. EarnIn offers excellent benefits, including healthcare, internet and cell phone reimbursement, a learning and development stipend, and potential opportunities to travel to our Mountain View, CA headquarters. Our salary ranges are determined by role, level, and location. WHAT YOU’LL DO Design build key backend components such as payroll and tax processing engines, ledger services, and pay cycle management. Develop services and APIs using C# and Go (Golang) that are robust, secure, and optimized for performance and maintainability. Partner closely with frontend engineers to design APIs and data models that enable intuitive, performant, and scalable user experiences. Contribute to frontend development for the payroll SaaS product, helping build and maintain user-facing features that are reliable, accessible, and easy to use. Collaborate closely with product managers, designers, and fellow engineers to deliver high-impact features that meet the needs of payroll customers end to end. Design, implement, and maintain scalable and reliable backend microservices for EarnIn’s new payroll SaaS product. Design, implement, and maintain services to integrate with partner platforms and expedite the customer onboarding process for EarnIn Payroll’s new SaaS product. Investigate and resolve production issues across the stack with a focus on root cause analysis, long-term stability, and continuous improvement. Contribute to building a modern, best-in-class payroll platform that handles time-critical financial workflows with precision and reliability. Conduct code reviews to ensure code quality, adherence to best practices, maintainability, and alignment with project requirements, while providing constructive feedback to team members across backend and frontend codebases. Ensure the delivery of high-quality software features within established timelines. WHAT WE’RE LOOKING FOR 4+ years of development experience in a fast-paced environment. Bachelor’s degree in computer science, computer engineering, or a related technical discipline, or equivalent industry experience. Experience using AI-assisted development tools (e.g., Copilot, Cursor, LLMs) is a plus. Proficient in one or more modern programming languages (e.g., Go, Python, C# or similar) with a solid understanding of software engineering best practices. Experience building or contributing to modern frontend applications (e.g., React, Vue, TypeScript, or similar frameworks) and a strong appreciation for user experience and usability is preferred. Hands-on experience working with relational databases. Cloud ... (truncated, view full listing at source)