Senior .NET Backend Engineer - REST APIs & Enterprise Apps

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

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.