Senior Backend Software Engineer

About us At Auctane, we are united by a passion to help businesses deliver — whatever their size, wherever they are, and however they operate. We make it possible for businesses to meet the ever-changing requirements of their industry and customer expectations. Auctane products enable hundreds of thousands of businesses to annually mail and ship billions of items — over $200 billion worth — to recipients around the globe. The Auctane family of mailing and shipping software products includes ShipStation, Stamps.com, ShipStation API, Metapack, GlobalPost, and Packlink. Our partners include Amazon, UPS, USPS, eBay, BigCommerce, Shopify, WooCommerce, and Walmart. Our values Win as One. Delight Customers. Deliver Great Outcomes. About the role We're seeking an experienced Senior Backend Engineer to join our engineering team. In this role, you'll architect and build scalable backend systems that power our applications, working across our modern tech stack to deliver robust, high-performance solutions. This position is focused on the Stamps.com brand. This position is hybrid (3 days per week in office) and is located in Austin, TX . What will you be doing? System Architecture & Design : Architect, build, and maintain scalable, robust backend services and microservices using C# and .NET. API Development : Create and consume secure REST APIs for seamless communication between backend services and front-end/mobile applications. Database Management : Design, query, and optimize relational databases (both SQL and NoSQL). Code Quality & Best Practices : Conduct rigorous code reviews, enforce engineering standards, and write clean, maintainable, production-ready code. Mentorship : Provide technical guidance, support, and mentorship to mid-level and junior developers. DevOps & Cloud : Collaborate with the infrastructure team to configure CI/CD pipelines, deploy applications to the cloud (AWS), and maintain different environments. Testing : Develop and maintain unit tests and integration tests to ensure application reliability. What are we looking for? Required Technologies: .NET - Strong proficiency in .NET, including ASP.NET Core, Entity Framework Core, and building RESTful APIs. Experience with C# design patterns and async programming AWS - Hands-on experience deploying and managing services on AWS, including EC2, Lambda, RDS, S3, CloudFront, SQS and API Gateway. Familiarity with infrastructure as code (Terraform, CloudFormation or CDK) React - Some experience with front-end JavaScript component libraries such as React. Additional Skills: Background in DevOps practice Strong understanding of database design (both SQL and NoSQL) Experience with containerization (Docker) and orchestration Knowledge of authentication/authorization patterns (OAuth, JWT) Understanding of microservices architecture and distributed systems Proficiency with Git and CI/CD pipelines Experience with monitoring, logging, and performance optimization Nice to Have TypeScript Experience with event-driven architectures and message queues Knowledge of caching strategies (Redis, CDN) We embrace AI-assisted development and expect our engineers to leverage these tools effectively. You should be comfortable using AI coding assistants (like GitHub Copilot, Claude, or similar tools) to accelerate development while maintaining code quality and security standards. Experience integrating AI capabilities into applications (OpenAI API, Claude API, or AWS Bedrock) is a plus. We value engineers who can critically evaluate AI-generated code, understand when to use these tools, and when human expertise is essential. Qualifications 5+ years of backend development experience Bachelor’s Degree in Computer Science Proven track record of building and scaling production applications Strong problem-solving abilities and attention to detail Experience mentoring junior developers Demonstrated ability to use AI tools responsibly to enhance productivity What do we offer? 🏠 We are a hybrid company…