Senior Software Engineer - C# / Java

Threecolts is the leading software suite for online & offline consumer brands, providing a powerful ecosystem of software solutions. The Senior Software Engineer will take ownership of features in C# and Java, designing and building scalable services and APIs, while collaborating with cross-functional teams to enhance customer value.

Responsibilities:

• You’ll take ownership of features across Inventory Lab’s C# and Java-based systems, delivering them from initial design through to production
• You’ll design and build clean, scalable services, APIs, and components that are maintainable, well-tested, and performant
• You’ll operate independently within a defined scope, making sound technical decisions and balancing speed with long-term quality
• You’ll play an active role in improving the systems you work on, debugging production issues, identifying root causes, and implementing durable fixes
• You’ll contribute to technical discussions, help evolve architecture within your domain, and raise the bar through thoughtful code reviews
• Collaboration is key: you’ll work closely with Product, QA, and DevOps to build features and improvements that deliver meaningful value to Inventory Lab customers

Requirements:

• 5–8+ years of professional software engineering experience
• Strong proficiency in C# and Java
• Experience building and maintaining backend services, APIs, and scalable application components
• Solid understanding of REST APIs, system design, and scalable application patterns
• Experience working with SQL databases and data modelling
• Familiarity with cloud infrastructure, ideally AWS
• Experience debugging production systems and resolving issues independently
• Comfortable working with Git, code reviews, and team-based development
• Ability to work across an existing codebase and improve quality without over-engineering