Principal Software Engineer

About Sezzle:

With a mission to financially empower the next generation, Sezzle is revolutionizing the shopping experience beyond payments, blending cutting-edge tech with seamless, interest-free installment plans that make shopping smarter and more accessible. We’re not just transforming payments; we’re redefining how people discover, interact with, and purchase the things they love while driving real impact on merchant sales through increased conversions and higher order values. As we continue to shape the future of fintech and retail, we’re building an innovative, dynamic team passionate about creating more than just a transaction but a truly unique shopping journey. If you’re excited about pushing boundaries in tech and delivering a game-changing experience for consumers and merchants alike, come join us at Sezzle and help create the future of shopping!

Compensation:

For this principal development role, with 12+ years of experience, the compensation range is $6,000 - $11,000 per month. This range acknowledges the extensive expertise, leadership capabilities, and significant contributions expected at this level, offering a competitive salary to reflect the value of advanced skills and experience.

Interview Process

We believe transparency is important at Sezzle. Regularly providing feedback while setting expectations is part of our culture starting with the interview process. Advancement through each step is not guaranteed.

• Application submitted (you are here)
• Wonderlic test (30-40 min)
• Interview with recruiters (30 min)
• Coding assessment (:1.5 hours)
• Interview with engineers (1 hour)
• Interview with engineering leadership (30-45 min)
• Offer!

We are seeking a talented and motivated best-in-class Principal Software Engineer. This role presents an exciting opportunity to thrive in a dynamic, fast-paced environment within a rapidly growing team, with abundant prospects for career advancement.

As a Principal Software Engineer with Sezzle, you will work with highly-motivated teams to tackle interesting and challenging problems across multiple areas of the organization. Your experience and guidance will help other members of the team level-up their own skills as well. You will spend your time working with AI/ML tooling to identify creative uses to fill existing and emerging gaps in the applications.

In this backend focused role, you will work closely with stakeholders from Product, Support and the business. You’ll also partner with other engineering teams to provide high-quality, scalable, and innovative solutions to internal and customer problems. Your day-to-day responsibilities will include designing, developing, and delivering new features, as well as unblocking and mentoring your teammates. Your work will generally focus on the lower level features and optimizations.

This role has both an internal and external focus, your contributions will make a meaningful difference in the day-to-day lives of your peers at Sezzle, enhancing their ability to support our business and customers, and you will have opportunities to take any feedback and iterate.

What You'll Do:

• Architect, design, and build scalable backend services and APIs primarily in Golang, leveraging AWS, RDS (MySQL/Postgres), and modern distributed patterns.
• Lead Sezzle’s AI enablement efforts, identifying opportunities to apply AI and automation to enhance developer productivity, internal tooling, and customer experiences.
• Partner with teams across the organization to integrate modern AI capabilities - Primarily around tools like Claude Code, Codex, Cursor and enhancing team productivity.
• Drive consistency and scalability across a distributed microservices architecture while maintaining performance and reliability.
• Establish and evolve engineering best practices for observability, security, and CI/CD across teams.
• Mentor engineers and champion a culture of learning, innovation, and operational excellence.
• Collaborate cross-functionally to translate business goals into technical roadmaps and deliver results that matter.

• 12+ years of professional software engineering experience, including significant backend experience.
• Deployed significant changes to a production application in the past 30 days.
• Strong proficiency in Golang, with experience building and maintaining RESTful APIs.
• Expertise with SQL-based RDBMS (MySQL, PostgreSQL) and experience optimizing schema and queries for performance at scale.
• Solid understanding of distributed systems design patterns (e.g., transactional outbox, event-driven architecture, queues).
• Demonstrated ability to bring new ideas forward, influence decisions, and lead complex technical initiatives.
• Bachelor’s degree in Computer Science.
• Demonstrated experience working with Claude or equivalent large language model tools is required; candidates must be comfortable leveraging AI to enhance productivity, research, and communication.

• Proficiency in observability tools (Prometheus, Grafana, Datadog, New Relic).
• Experience with AWS cloud infrastructure, mainly AWS Aurora RDS, both MySQL and Postgres.
• Experience in fintech, payments, BNPL, or consumer lending - familiarity with financial compliance, credit decisioning, or transaction processing systems.
• Experience with CI/CD pipelines and containerized microservices (Docker, Kubernetes).
• Working knowledge of TypeScript, React, or React Native.
• Familiarity with AI/ML tooling (e.g., OpenAI API, LangChain, Hugging Face, or custom LLM integrations).
• Track record of shipping commercial APIs and data-driven applications in high-growth environments.
• Proven leadership in guiding technical direction, improving system reliability, and scaling engineering organizations.

• You have relentlessly high standards - many people may think your standards are unreasonably high. You are continually raising the bar and driving those around you to deliver great results. You make sure that defects do not get sent down the line and that problems are fixed so they stay fixed.
• You’re not bound by convention - your success—and much of the fun—lies in developing new ways to do things
• You need action - speed matters in business. Many decisions and actions are reversible and do not need extensive study. We value calculated risk-taking.
• You earn trust - you listen attentively, speak candidly, and treat others respectfully.
• You have backbone; disagree, then commit - you can respectfully challenge decisions when you disagree, even when doing so is uncomfortable or exhausting. You have conviction and are tenacious. You do not compromise for the sake of social cohesion. Once a decision is determined, you commit wholly.
• You deliver results - you focus on the key inputs and deliver them with the right quality and in a timely fashion. Despite setbacks, you rise to the occasion and never settle.

• Languages: Golang, Typescript, Python
• Frontend: Typescript - React and React Native
• Backend: Golang
• Database: MySQL, Postgres, Elasticsearch
• DevOps & Cloud: AWS, Kubernetes
• Version Control: Git
• CI/CD: Gitlab
• Testing: Developer and AI-driven, focus on automated end-to-end, integration, and unit tests
• Open Source: Sezzle is focused on using open source, and we build what we can before buying!

At Sezzle, we are more than just brilliant engineers, passionate data enthusiasts, out-of-the-box thinkers, and determined innovators; we are skilled musicians, yogis, cyclists, chefs, golfers, dog-lovers, and rock-climbers. We believe in surrounding ourselves with not only the best and the brightest individuals, but those that are unique and purpose-driven in all that they do. Our culture is not defined by a certain set of perks designed to give the illusion of the traditional startup culture, but rather, it is the visible example living in every employee that we hire.

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