Senior .NET Engineer

Company Description

DTalent Human Services Consulting is dedicated to providing high-quality, efficient recruitment services by leveraging advanced AI technology to match the right talent with the right opportunities. DTalent is committed to creating meaningful connections between employers and professionals. We prioritize innovation, speed, and precision to meet the unique needs of businesses and candidates. By integrating cutting-edge AI technology, DTalent ensures optimal solutions for workforce and talent acquisition.

Position: Senior .NET Engineer (RBAC & Authorization Architecture)

Salary range: Up to 70M NET

Contract duration: Long-term

Working time: Mon to Fri. From 3pm - 12am (VNT)

Employment type: Full-time, open for 2nd job candidates

Location: Remote working, based in Viet Nam

Domain: eCoach - live production SaaS (Call center / BPO)

Client Nationality: Germany

Interview process: 2 rounds

Project Context:

eCoach is a live, multi-tenant SaaS platform running at ccw.ecoach.cloud. It is used by call center companies to manage quality assurance: agents handle customer contacts (call, chat, mail), auditors evaluate those contacts via structured monitoring sheets (templates), and coaches conduct improvement sessions based on the results.

The platform was extracted from an internal PHP-based ERP and rebuilt as an API-first .NET SaaS. V1 is in production with real paying customers. The team has identified a fundamental architectural issue in the current role and permission system and is building V2 on a parallel branch. This is the primary work the new developer will join.

Context: Why V2 and Why Now

The team built V1 quickly and got to production with paying customers, but the role system was not scalable. An auditor's ability to monitor a process should be scoped by which team they belong to and which project the process belongs to V1 only checks global role, not context. This creates a multitude of access combinations that V1 cannot express cleanly. V2 is designed to fix this at the architecture level. The developer who joins owns this problem end-to-end.

Problem description file: https://drive.google.com/file/d/1mFVU2a1pIrIgYIab5v5Nuns9u8Dd_wuZ/view?usp=sharing

Technology Stack:

• Client App: C# .NET 10 · Blazor WebAssembly · MudBlazor · Material Design · JavaScript (minimal)
• API: C# .NET 10 · Microsoft Identity · Finbuckle Multitenancy · Minimal API · CQRS (Mediator/MediatR)
• Database: PostgreSQL 18 · Entity Framework Core · Code-First Migrations
• Infrastructure: Azure App Service · Bicep (IaC) · Docker · GitHub
• Cross-cutting: SSO / JWT · RBAC (Scoped Roles) — primary task · Localization (i18n) · Logging · Testing

Responsibilities

• Design and implement the V2 Scoped RBAC system: team-scoped and project-scoped permissions layered on top of global roles (auditor, agent, coach)
• Rebuild and complete user management (currently incomplete in V1)
• Implement claims enrichment and policy-based authorization in the .NET Identity + JWT pipeline
• Develop features using Minimal API + CQRS (MediatR) + Ardalis.Specification patterns, the established codebase pattern (fullstackhero-style starter kit)
• Work with a non-technical product owner to translate business requirements into technical solutions, proactively flag architectural risks
• Support localization: the platform serves international customers; UI is multi-language (German confirmed)
• Write unit and integration tests; maintain code quality per ISO 27001 security standards
• Participate in future AI integration planning: AI agent for call transcription and automated monitoring (roadmap item)

Required Skills

• Language proficiency: Fluent English communication (daily collaboration with European team)
• 10+ years hands-on C# / .NET Core · recent experience with .NET 6+ (ideally .NET 8 or 10)
• Demonstrated experience with claims-based / policy-based authorization JWT, roles, scopes, or RBAC redesign in a real SaaS or multi-tenant context
• Solid understanding of CQRS pattern and MediatR must be able to write a handler from scratch in live coding
• Entity Framework Core — code-first migrations, query optimization, multi-tenant data isolation
• Blazor (WASM or Server) experience — OR strong frontend .NET component experience with ability to learn MudBlazor quickly
• Finbuckle.MultiTenancy or equivalent multi-tenant architecture understanding

Working Style

• Comfortable working with incomplete requirements: product owner needs developer support to define solutions

• Proactive communicator: raises blockers early, documents decisions, asks clarifying questions

• Security-conscious: company holds ISO 27001 since 2009; data isolation and auth must be done correctly

• Long-term mindset: this is an ongoing product, not a short engagement