Senior .Net Developer($7600)

Rapsys Technologies Pte Ltd.; Singapore; On-site; SGD 90,000 - 130,000; Full time

Job summary

Rapsys Technologies Pte Ltd. in Singapore is seeking a Senior .Net Developer to design, develop, and maintain enterprise-level backend services using .NET 8 and ASP.NET Core.

You will work with PostgreSQL, implement JWT and LDAP authentication, containerize with Docker, and collaborate with frontend teams to define clear API contracts. Office-based role with a focus on code quality and CI/CD.

Qualifications

• 5+ years of backend development in C#/.NET (ASP.NET Core preferred).
• Strong REST API design and secure auth patterns.
• Experience with relational DBs and ORMs (EF or equivalent).
• Familiarity with containers (Docker) and CI/CD pipelines.
• Proficient Git and collaborative workflows.

Responsibilities

• Design, build, and maintain RESTful APIs and backend services with .NET 8/ASP.NET Core.
• Work with PostgreSQL/SQL Server; design schemas and optimize queries.
• Implement authentication/authorization incl. JWT, Windows/Negotiate, LDAP; integrate with AD.
• Collaborate with frontend teams to define API contracts for React/TypeScript apps.
• Containerize services with Docker; support CI/CD pipelines and testing.

Skills

.NET backend

C# / ASP.NET Core

REST API design

Authentication

PostgreSQL / SQL Server

Docker

CI/CD pipelines

Git

Problem-solving

Communication

Tools

PostgreSQL

SQL Server

Entity Framework

Docker

Git

Jenkins / GitLab CI

Job description

We're Hiring: Senior .Net Developer!

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!

Location: Singapore, Singapore
Work Mode: Work from Office
Role: Senior .Net Developer

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 skills
• Clear 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