Principal Software Engineer, Architecture - Platform Modernization

Principal Software Engineer, Architecture - Platform Modernization

isolved is executing a live, in-production decomposition of a 7M+ line HCM monolith into modern, event-driven microservices across key domains including Tax, Benefits, Time, Payroll, and Shared Logic. Using the Strangler Fig pattern, small, high-impact engineering teams extract and deploy independent services on Azure, each with its own data model. This work happens without disrupting real customers, requiring precision, ownership, and strong execution. Engineers play an active role in technical decisions, but the primary focus is delivering domain extraction at scale within a high-expectation, fast-moving environment.

Core Job Duties

• Designing and implementing modern, scalable API architectures that support isolved's integration ecosystem and partner network
• Defining API contracts, versioning strategies, and governance standards that ensure consistency and reliability across the platform
• Driving the migration of legacy integration endpoints to modern RESTful and event-driven patterns as part of the integration modernization initiative
• Building API consumers and producers with a strong focus on performance, security, and backward compatibility, and elevating the team's practices through code reviews, pairing, and leading by example
• Performing code reviews to ensure API implementations meet quality standards and follow established patterns
• Collaborating with product management and partner-facing teams to understand integration requirements and translate them into technical specifications
• Identifying and resolving performance bottlenecks in API infrastructure, including latency, throughput, and reliability issues
• Establishing and documenting best practices for API development, testing, and monitoring across the engineering organization
• Using AI-assisted development tools - including agentic coding, spec-driven development, and AI-augmented code review - as a core part of your daily workflow to maximize velocity and code quality, and helping establish AI-augmented development practices across the team

Minimum Qualifications

• 7+ years of experience developing web applications and services, including 3+ years in cloud-native environments
• Proficiency in Azure, .NET/C#, ASP.NET Core Web APIs, and SQL Server
• Strong experience designing and building microservices and RESTful APIs
• Hands-on experience with API gateways and API management best practices
• Demonstrated use of AI-assisted development tools in professional workflows
• Solid understanding of unit testing, SOLID principles, and secure API design (OAuth 2.0)
• Familiarity with JavaScript and OpenAPI /Swagger documentation standards
• Preferred: experience with Azure API Management, Cosmos DB/NoSQL, messaging systems (Service Bus/Event Grid), containers, or large-scale systems

Preferred Qualifications

• Experience in HCM/payroll domains and familiarity with Azure services ( Dapr, Service Bus, Container Apps, API Management) and CDC tools like Debezium

About isolved

isolved is an employee experience leader, providing intuitive, people-first HCM (Human Capital Management) technology. Our solutions are delivered directly or through our partner network to more than five million employees and 145,000 employers - who use them every day to boost performance, increase productivity, and accelerate results while reducing risk. Our HCM platform, isolved People Cloud, seamlessly connects and manages the employee journey across talent management, HR & payroll, workforce management and engagement management functions. No matter the industry, we help high-growth organizations employ, enable and empower their workforce by transforming employee experience for a better today and a better tomorrow. For more information, visit

EEO Statement

isolved is an equal opportunity employer. All applicants will be considered for employment without attention to race, color, religion, sex, sexual orientation, gender identity, national origin, veteran or disability status. isolved is a progressive and open-minded meritocracy. If you are smart and good at what you do, come as you are.

Disability Accommodation

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