Senior Application Developer (.NET & Ruby on Rails)

Role: Senior Application Developer (.NET & Ruby on Rails) Location: Carrollton, TX (Onsite) Experience: 8+ Years Employment Type: Full-Time Job Description We are seeking an experienced Senior Application Developer (.NET & Ruby on Rails) to design, develop, enhance, and support enterprise applications that automate key business processes, including pricing, trading, hedging, pooling, shipping, and other operational functions. The ideal candidate should possess strong expertise in .NET technologies, Ruby on Rails, C#, and Open Source/LAMP technologies , with experience delivering scalable, secure, and high-performance applications in an Agile environment. Key Responsibilities Design, develop, enhance, and maintain enterprise applications using .NET, C#, Ruby on Rails, and Open Source technologies . Build scalable, secure, and high-performing web applications and RESTful web services. Participate in the complete Software Development Life Cycle (SDLC), including requirements analysis, design, development, testing, deployment, and production support. Develop high-quality code using BDD/TDD methodologies with frameworks such as RSpec and NUnit . Create, maintain, and optimize REST APIs and backend services. Prepare deployment packages and support application releases across development, QA, and production environments. Troubleshoot production issues, perform root cause analysis, and implement permanent fixes. Collaborate with business users, product owners, QA teams, and technical stakeholders to gather requirements and deliver effective solutions. Develop and optimize database objects, queries, and stored procedures using MySQL, PostgreSQL, and SQL Server . Apply software engineering best practices, including design patterns, code refactoring, unit testing, and code reviews. Work with Linux-based environments and Open Source technologies to support application hosting and deployment. Maintain technical documentation, deployment guides, release notes, and knowledge base articles. Participate in Agile ceremonies, sprint planning, backlog refinement, and retrospectives. Mentor junior developers and contribute to continuous improvement initiatives. Required Qualifications 8+ years of experience in application development using .NET, C#, and Ruby on Rails . Strong hands-on experience with ASP.NET, .NET Framework/.NET Core, Ruby, Rails, and RESTful Web Services . Experience with Linux , Apache, and Open Source/LAMP environments. Strong knowledge of MySQL, PostgreSQL, and Microsoft SQL Server . Experience implementing BDD/TDD using RSpec, NUnit, or similar testing frameworks . Solid understanding of software design patterns, object-oriented programming, refactoring, and unit testing. Experience with Git and version control best practices. Knowledge of Agile/Scrum development methodologies. Strong analytical, troubleshooting, and problem-solving skills. Excellent communication and collaboration skills. Preferred Qualifications Experience in Financial Services , particularly Mortgage and Mortgage-Backed Securities (MBS) domains. Exposure to cloud platforms and CI/CD pipelines. Experience with application performance tuning and production support. Familiarity with containerization technologies such as Docker and Kubernetes is an added advantage. Technical Skills Programming: C#, .NET Framework/.NET Core, Ruby, Ruby on Rails Web Technologies: ASP.NET, RESTful APIs, Web Services Databases: MySQL, PostgreSQL, SQL Server Operating Systems: Linux Web Server: Apache Testing: RSpec, NUnit, BDD, TDD, Unit Testing Development Practices: Agile, Scrum, SDLC, Design Patterns, Refactoring Version Control: Git Tools: Visual Studio, VS Code, Jira, Azure DevOps (preferred) Domain: Financial Services, Mortgage, Mortgage-Backed Securities (Preferred) AceStack LLC