Full Stack .NET Engineer

We are looking for a Full Stack .NET Engineer to join our client's team. In this role, strong software engineering fundamentals and expertise in modern .NET versions are key, complemented by a willingness to work on Web Frontend tasks and practical familiarity with SQL Server and Azure environments.

We seek an engineer who brings technical intuition, solid problem-solving skills, and a security-conscious approach to building clean, maintainable software solutions.

About First Factory We are a software development company with over two decades of experience, boasting a dynamic team of 175+ professionals actively engaged in diverse projects across various industries. We invite you to join us on this journey as we thrive and embrace fresh challenges.

Key Responsibilities

• Design, build, and maintain high-performing, scalable applications using modern .NET (C#) and standard design patterns like CQRS.
• Develop and maintain frontend components using ASP.NET Core MVC, Razor, Blazor Server, Bootstrap, Sass, and JavaScript/jQuery.
• Build and deploy application components in Azure (App Service, Azure Functions, Blob Storage) using cloud security fundamentals, ensuring sensitive data, API keys, and credentials are securely managed via Key Vault and Managed Identities.
• Work with SQL Server, modern versions of EF Core, and Dapper to support application logic, write efficient T-SQL queries, and handle data persistence reliably.
• Create and integrate robust Web APIs (ASP.NET Core Web API, SignalR, JWT Bearer) and HTTP Clients (Refit, RestSharp).
• Write clean, secure, and maintainable code, actively participate in code reviews, and contribute to standard software quality practices through unit testing frameworks like xUnit, Moq, and FluentAssertions.
• Collaborate with cross-functional team members to refine requirements, clarify scope, and deliver stable features.
• Communicate effectively with technical and non-technical stakeholders, share technical knowledge, and advocate for safe engineering practices.

Requirements

• 3+ years of professional experience delivering web applications with modern .NET (C#), demonstrating enthusiasm for Full Stack development or a clear willingness to tackle Frontend responsibilities.
• Solid understanding of core software engineering concepts, API design, and dependency injection.
• Experience with Web Frontend technologies, including ASP.NET Core MVC, Razor, Bootstrap, and JavaScript/jQuery.
• Practical familiarity with Azure basics and cloud security fundamentals (understanding secure handling of credentials, API keys, and application configurations).
• Working knowledge or practical experience with SQL Server database development, including Object-Relational Mappers like EF Core and micro-ORMs like Dapper.
• Strong problem-solving ability and awareness of software quality and security practices.
• Excellent verbal and written English communication skills.
• Experience working with Agile methodologies and CI/CD pipelines such as Azure DevOps YAML.

Nice to Have

• Experience with the MediatR library or similar implementations of the Mediator pattern.
• Familiarity with observability and logging tools like Serilog and Application Insights.
• Knowledge of document generation libraries (such as EPPlus, iText, or RazorLight).
• Familiarity with utilities such as AutoMapper, FluentValidation, or Quartz.NET.

For over 25 years, First Factory has been a place where collaborative excellence meets modern technologies. We’re a strong team building exceptional software solutions from Costa Rica and LATAM for primarily US-based clients. With industry-low turnover, top eNPS globally, and 5 consecutive Inc. 5000 awards, we foster an environment where talented engineers thrive on challenging projects using modern tech stacks.