Senior Software Engineer .NET

About this role

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 As a Senior Software Engineer, you will design, develop, and maintain complex software components that align with business and technical requirements.

You will take ownership of feature implementation, troubleshoot technical challenges, and collaborate with cross-functional teams to deliver scalable solutions. Your role will involve contributing to technical discussions, refining best practices, and supporting junior engineers through code reviews and knowledge sharing. Your expertise in programming and software engineering will be essential for achieving project goals and ensuring the delivery of high-quality products.

This role is based in Madrid. What will you be doing? Contribute to system architecture discussions and develop software components aligned with functional and non-functional requirements. Creating high-quality, maintainable code in accordance with company best practices and standards. Participate in software testing, debugging, and optimization to ensure performance, scalability, and reliability. Develop and maintain cloud-based APIs, microservices, and integrations as part of a collaborative engineering team.

Support junior engineers through code reviews, pair programming, and sharing technical insights. Collaborate with the team to refine task prioritization and align work with project goals. Tackling complex problems requiring deep analysis and evaluation of diverse factors. Collaborating closely with other teams and departments, such as product teams to ensure solutions meet business and technical requirements. Communicate effectively with team members and external stakeholders to clarify requirements and share progress updates.