Senior .Net Developer($7600)

RAPSYS TECHNOLOGIES PTE LTD; Singapore; On-site; SGD 110,000 - 170,000; Full time

Job summary

RAPSYS TECHNOLOGIES PTE LTD in Singapore is seeking a Senior .NET Developer to design, develop, and maintain enterprise-grade backend services using .NET 8 / ASP.NET Core. You will build RESTful APIs, work with PostgreSQL via EF, implement authentication, containerize with Docker, and collaborate with frontend teams while ensuring code quality and CI/CD pipelines.

The ideal candidate has 5+ years of experience, strong debugging and problem-solving skills, and a proven ability to work across

Qualifications

• 5+ years of professional backend experience in C#/.NET (ASP.NET Core preferred).
• Strong REST API design and secure coding practices.
• Experience with relational databases (PostgreSQL/SQL Server) and ORMs.
• Familiarity with Docker and CI/CD pipelines.
• Proficient in Git and collaborative development workflows.
• Solid debugging, troubleshooting, and problem-solving skills.

Responsibilities

• Design, build, and maintain RESTful APIs and backend services.
• Work with PostgreSQL schemas and data access layers via EF.
• Implement authentication/authorization patterns (JWT, LDAP/AD).
• Integrate backend with enterprise systems and front-end teams.
• Containerize services with Docker and support CI/CD pipelines.
• Write tests, perform code reviews, and uphold quality standards.
• Troubleshoot production issues with observability tooling.
• Contribute to architectural decisions for new services.

Skills

Backend development

REST API design

Authentication/Authorization

CI/CD pipelines

Unit testing

Troubleshooting

Git version control

Cross-functional collaboration

Tools

Docker

Git

Entity Framework

PostgreSQL

ASP.NET Core

Job description

We are looking for a skilled and experienced Senior .Net Developer to join our dynamic team in Singapore. This role requires a strong background in designing, developing, and maintaining enterprise-level applications using the .Net framework. If you have a passion for clean code, innovative solutions, and enjoy working collaboratively in an office setting, we want to hear from you!

What You'll Do

• Design, build, and maintain RESTful APIs and backend services using .NET 8 / ASP.NET Core
• Work with PostgreSQL (via Npgsql/Entity Framework) to design schemas, write efficient queries, and manage data access layers
• Implement and maintain authentication/authorization flows, including JWT bearer auth, Windows/Negotiate authentication, and LDAP/Active Directory integration
• Integrate backend services with third-party and enterprise systems (e.g., ServiceNow-style ITSM platforms, directory services, internal data APIs)
• Collaborate with frontend engineers to design clean API contracts consumed by React/TypeScript applications
• Containerize services with Docker and support CI/CD pipelines (Jenkins, GitLab CI)
• Write unit and integration tests, participate in code reviews, and uphold code quality standards (e.g., SonarQube)
• Troubleshoot and resolve production issues across the stack, with structured logging (log4net) and observability practices
• Contribute to architecture decisions for new services and the evolution of existing ones

What We're Looking For

• 5+ years of professional experience building backend services in C# / .NET (ASP.NET Core preferred)
• Strong understanding of REST API design, authentication/authorization patterns, and secure coding practices
• Experience working with relational databases (PostgreSQL, SQL Server, or similar) and ORMs (Entity Framework or equivalent)
• Familiarity with containerization (Docker) and CI/CD pipelines
• Experience with version control (Git) and collaborative development workflows
• Strong debugging, troubleshooting, and problem-solving skillsClear written and verbal communication, with the ability to work cross-functionally with frontend, QA, and infrastructure teams

Nice to Have (Advantages)

• Full-stack development experience — comfort working across the stack with React/TypeScript front ends, from API design to UI integration
• AI/ML knowledge — familiarity with applying AI/LLM tooling to developer workflows, automation, or product features (e.g., integrating LLM APIs, prompt engineering, or AI-assisted development practices)
• Automation experience with Python and/or Ansible Automation Platform (AAP) — building or maintaining scripts, playbooks, or jobs for infrastructure automation, compliance checks, or operational tooling

What Makes You Stand Out

• Experience integrating enterprise systems with LDAP/Active Directory or similar identity providers
• Exposure to hybrid environments where .NET services, Node/React front ends, and Python-based automation coexist and need to interoperate
• A track record of improving reliability, security, or maintainability of backend systems in a production environment