Senior .NET Microservices Engineer — Cloud & AI-Driven SDD

optimum solutions (singapore) pte ltd; Singapore; On-site; SGD 60,000 - 120,000; Full time

Job summary

Optimum Solutions (Singapore) Pte Ltd is seeking a full-stack developer to design, build, and maintain microservices-based applications using .NET Core/.NET 8, Java, EF, Docker, DDD, OAuth, and AWS. The role includes REST API development, legacy migration, and security hardening.

The frontend uses ASP.NET with WebForms, HTML/CSS/JS, and a component library managed with Storybook. Collaboration with UX/UI designers is essential, along with AI-assisted coding via Spec Driven Development (SDD).

Qualifications

• Proven professional experience with .NET Core stack and modern backend technologies.
• Experience building microservices and event-driven patterns.
• Proficiency in EF for database interactions.
• Familiarity with Docker and containerization principles.
• Knowledge of DDD and security best practices.
• Experience with AWS services (S3, Lambda, API Gateway, RDS).
• Frontend proficiency in HTML/CSS/JS and ASP.NET/WebForms.

Responsibilities

• Design, develop, and maintain microservices architecture using .NET Core, .NET 8 and Java.
• Implement event-driven communication between microservices.
• Utilize EF for efficient database interactions.
• Containerize applications using Docker for scalability.
• Apply DDD principles for modular code architecture.
• Implement OAuth for authentication and authorization.
• Develop and enforce security best practices.
• Use AWS services for backend development.
• Develop RESTful APIs for frontend-backend communication.
• Apply Spec Driven Development (SDD) with Claude AI technologies.
• Support and maintain legacy .NET Framework apps and migrations.
• Manage hosting and deployment on IIS and Windows Server with config transformations.
• Frontend development with ASP.NET including WebForms; responsive UI with HTML/CSS/JS.
• Collaborate with UX/UI designers; review unit tests and maintain a design system with Storybook.
• Ensure performance optimization and troubleshooting across stack.
• Integrate OpenTelemetry for distributed tracing and observability.
• Work with Oracle databases and query optimization.

Skills

NET Core stack

C#

Java

Microservices

Entity Framework

Docker

DDD

OAuth

AWS

REST APIs

Storybook

OpenTelemetry

Oracle DB

IIS/Windows Server

OpenAI Claude/SDD

Tools

Docker

Storybook

OpenTelemetry

Job description

Optimum Solutions (Singapore) Pte Ltd is seeking a full-stack developer to design, build, and maintain microservices-based applications using .NET Core/.NET 8, Java, EF, Docker, DDD, OAuth, and AWS. The role includes REST API development, legacy migration, and security hardening.

The frontend uses ASP.NET with WebForms, HTML/CSS/JS, and a component library managed with Storybook. Collaboration with UX/UI designers is essential, along with AI-assisted coding via Spec Driven Development (SDD).