Senior Full-Stack Developer (.NET / React)

Salt Square is a growing outsourcing company providing high-quality software development services to clients across a wide range of industries. Our team is composed of skilled and dedicated professionals delivering innovative solutions that meet and exceed client expectations.

Our mission is to build reliable, scalable, and future-ready digital solutions tailored to each client’s unique business needs. We foster a team-first culture where collaboration, continuous learning, and technical excellence are core values. From supporting startups in launching their first products to helping global enterprises scale their operations, we strive to deliver outstanding value on every project.

We are looking for a strong Senior .NET/React Developer to join our engineering team. The primary focus is backend development in .NET Core/C#, with regular contributions to the React/TypeScript frontend. You will be expected to drive architectural decisions, set technical direction, mentor mid-level developers, and ship production-quality code across the full stack.

Typical Responsibilities

• Develop and maintain full-stack features with a backend-heavy split (roughly 70/30 .NET Core to React)

• Design, build, and document RESTful APIs consumed by web clients

• Drive architectural decisions and take ownership of technical direction within the team

• Mentor mid-level developers, conduct code reviews, and uphold engineering standards

• Identify and resolve performance bottlenecks, technical debt, and reliability issues proactively

• Participate in Agile sprint ceremonies, contribute to estimation, and communicate blockers and risks early

• Leverage AI-augmented development practices to accelerate delivery and improve code quality

• Deep proficiency in .NET Core, C#, and ASP.NET Core Web API, with a track record of building and scaling backend services in production

• Strong working knowledge of React.js and TypeScript, able to build, maintain, and review frontend code with confidence

• Experience with SQL databases (PostgreSQL or SQL Server), including query optimization, schema design, and performance tuning

• Hands-on experience with Entity Framework Core or equivalent ORM, including migrations and complex query patterns

• Proven ability to design, build, and document RESTful APIs with attention to versioning, error handling, and contract-first approaches

• Solid understanding of software design patterns, SOLID principles, and clean architecture

• Version control with Git and experience with collaborative branching strategies

• Agile/Scrum methodology experience with clear communication and the ability to unblock others