.NET Developer

MateCareer; Jawa Barat; On-site; IDR 200,880,000 - 312,480,000; Full time

Job summary

PT Adaya Solusi Teknologi in Bandung, Jawa Barat, Indonesia seeks an experienced .NET Developer to design, develop, and maintain scalable applications. You will build RESTful APIs, apply clean architecture and DDD, and ensure code quality with automated tests.

Collaborate with Product, Design, QA, and DevOps to deliver production-ready software, mentor juniors, and help shape the technical roadmap while adapting to client needs and legacy systems.

Qualifications

• Minimum 3 years of experience as a .NET Developer, including 2+ years on production systems.
• Expertise in modern C# and .NET / ASP.NET Core.
• Strong understanding of OOP, SOLID, design patterns, and clean architecture / DDD.
• Proven experience designing RESTful APIs with proper versioning and auth.
• Proficiency in EF Core with raw SQL / Dapper usage awareness.
• Strong SQL Server skills: schema, indexing, queries, transactions.
• Experience with unit/integration testing (xUnit/NUnit, Moq, TestContainers).
• Familiarity with Git and GitFlow/trunk-based development.
• Experience deploying to IIS, containers, or cloud platforms.
• Ability to understand and improve legacy codebases; client-side placement.

Responsibilities

• Design end-to-end application architectures for new features and refactors.
• Act as technical decision-maker for stacks, patterns, and implementation.
• Develop production-grade, testable, observable, secure, well-documented code.
• Lead code reviews and uphold engineering standards across the team.
• Mentor junior and mid-level developers and support their growth.
• Collaborate with Product, Design, QA, and DevOps for quality delivery.
• Profile performance, troubleshoot, and perform root cause analysis.
• Contribute to technical roadmap by reducing debt and driving improvements.
• Ensure non-functional requirements: security, performance, reliability, observability.

Skills

C#

ASP.NET Core

OOP

SOLID

Design Patterns

DDD

REST APIs

Entity Framework Core

SQL Server

Unit Testing

Git

CI/CD

Azure

Docker

Kubernetes

OpenTelemetry

Tools

SQL Server

Dapper

xUnit/NUnit

Moq

TestContainers

GitFlow

Job description

Job opportunity for .NET Developer at PT Adaya Solusi Teknologi in KAB. BANDUNG, JAWA BARAT, Indonesia.

Kualifikasi:

Key Responsibilities

• Design end-to-end application architectures for both new features and existing system refactoring, considering scalability, maintainability, and cost efficiency.
• Act as a technical decision-maker for technology stacks, design patterns, and implementation approaches within your area of responsibility.
• Develop production-grade code that is testable, observable, secure, and well-documented.
• Lead code reviews, provide constructive feedback, and uphold engineering standards across the team.
• Mentoring junior and mid-level developers, supporting both their technical growth and professional mindset development.
• Collaborate closely with Product, Design, QA, and DevOps teams to ensure smooth and high-quality delivery.
• Perform performance profiling, troubleshoot complex production issues, and conduct thorough root cause analysis.
• Contribute to the technical roadmap by identifying technical debt, proposing improvements, and driving implementation.
• Ensure the quality of non-functional requirements, including security, performance, reliability, and observability.

Required Qualifications

• Minimum 3 years of experience as a .NET Developer, including at least 2 years working on production systems used by real users.
• Expertise in modern C# (LINQ, async/await, generics, delegates, nullable reference types) and .NET / ASP.NET Core.
• Strong understanding of Object-Oriented Programming (OOP), SOLID principles, Design Patterns, and Clean Architecture / Domain-Driven Design (DDD).
• Proven experience designing and developing high-quality RESTful APIs, including resource modeling, versioning, error handling, authentication, and authorization.
• Proficiency in Entity Framework Core, with a clear understanding of when to utilize raw SQL or Dapper.
• Strong expertise in SQL Server, including schema design, indexing strategies, query plan analysis, stored procedures, and transaction isolation.
• Experience with unit testing and integration testing frameworks such as xUnit/NUnit, Moq, and TestContainers.
• Familiarity with Git and collaborative branching strategies such as GitFlow and trunk-based development.
• Experience deploying applications to production environments, whether on IIS, containers, or cloud platforms, with a solid understanding of post-release application lifecycle management.
• Ability to quickly understand, maintain, and improve existing codebases, including legacy systems.
• Willing to be placed at the client side

Preferred Qualifications

• Experience with microservices and event-driven architectures (RabbitMQ, Kafka, Azure Service Bus).
• Familiarity with Docker, Kubernetes, and container orchestration.
• Experience with cloud platforms, particularly Microsoft Azure (App Service, Azure Functions, Azure SQL, Service Bus, Key Vault).
• Familiarity with modern CI/CD practices and tools such as Azure DevOps, GitHub Actions, and GitLab CI.
• Understanding of caching strategies (Redis, in-memory caching, CDN) and their appropriate use cases.
• Experience with observability practices, including structured logging (Serilog), metrics collection, and distributed tracing (OpenTelemetry).
• Familiarity with modern frontend frameworks such as Blazor, React, or Angular.
• Experience working with SOAP/WCF integrations for legacy enterprise, banking, or government systems.
• Contributions to open-source projects, technical blogs, or developer communities are not required but are considered a strong plus.

What We Look For

• Ownership You treat the systems and codebases you work on as if they were your own, taking responsibility from design through post-release support.
• Pragmatism You understand that the best solution is not always the most sophisticated one, but the one that best fits the business needs and team context.
• Strong Communication Skills You can clearly communicate technical decisions to both fellow developers and non-technical stakeholders.
• Curiosity You consistently ask "why" - whether regarding business requirements or technical decisions.
• Mentorship Mindset You genuinely enjoy sharing knowledge and helping others grow.
• Calm Under Pressure You remain composed and think clearly when handling critical production incidents, even at 2:00 AM.

Red Flags (Considerations During Evaluation)

• Claiming seniority without experience in writing automated tests.
• Inability to explain the trade-offs behind past technical decisions.
• Consistently blaming frameworks, libraries, or team members when issues arise.
• Having no awareness of or engagement with the .NET ecosystem over the past 2-3 years.