Principal Software Engineer

thrively; California (MO); On-site; USD 180,000 - 240,000; Full time

Job summary

Thrively is seeking a Senior Principal Software Engineer to own the architecture and technical direction of a high-volume financial platform. You’ll stay hands-on while guiding APIs, microservices, and overall engineering standards to scale a 500–800 TPS system.

You’ll collaborate with Product, Architecture, and Engineering to build secure, reliable systems, driving security, observability, and performance improvements across the stack.

Qualifications

• 12+ years of hands-on software engineering experience.
• At least 5 years of technical leadership experience.
• Advanced experience with C#, .NET, and SQL.
• Strong hands-on experience with Azure and cloud-native architecture.
• Experience with Azure services such as APIM, Azure SQL, Cosmos DB, and Key Vault.
• Deep understanding of RESTful APIs, OAuth2, and OpenAPI.
• Strong experience with microservices and event-driven architectures.
• Experience with technologies such as Azure Service Bus and Event Hubs.
• Strong understanding of containers, caching, Git, DevOps, and CI/CD.
• Experience implementing observability using platforms such as Datadog or Grafana.
• Ability to troubleshoot complex production systems and perform structured root-cause analysis.
• Strong communication, technical leadership, and mentoring skills.

Responsibilities

• Own the architecture and technical direction of the APIs and microservices underpinning the platform, setting standards other teams build against
• Design scalable, secure, and high-performance software systems
• Make high-level architectural decisions and establish coding standards, design patterns, and engineering principles
• Refactor and extend existing systems while designing for long-term flexibility and scalability
• Develop prototypes and proofs-of-concept to evaluate new technologies and reduce implementation risk
• Drive best practices across code reviews, CI/CD, automated testing, and observability
• Build and improve monitoring and alerting capabilities to support SLA requirements
• Lead incident response and root-cause analysis for complex production issues
• Help ensure mission-critical, customer-facing applications remain reliable and performant
• Champion security and compliance best practices across the platform
• Partner with Product Managers, Architects, and Engineering teams to translate business requirements into technical solutions
• Mentor engineers and help raise engineering standards across the organization
• Drive long-term technical strategy and architectural decision-making
• Evaluate and introduce new technologies, frameworks, and development methodologies
• Work within an AI-driven SDLC environment using tools such as GitHub Copilot

Skills

C#/.NET

Azure

SQL

REST APIs

OpenAPI

Microservices

Event-driven

DevOps

CI/CD

Observability

Git

Tools

Azure

Datadog

Grafana

GitHub Copilot

Azure Service Bus

Job description

Thrively is partnering with a leading financial technology company building highly scalable platforms that power embedded financial services across a broad partner ecosystem.

We're looking for a highly experienced Principal Software Engineer to help own the architecture and technical direction of a mission-critical, highly transactional platform processing approximately 500–800 transactions per second.

This is an opportunity for a senior technical leader who still enjoys being hands-on, solving complex engineering problems, and setting the technical standards behind high-volume financial systems.

The Role

This is not a purely architectural or people-management role. You'll remain deeply involved in the technology while owning key architectural decisions, technical strategy, engineering standards, and the APIs and microservices underpinning the platform.

You'll work closely with Product, Architecture, and Engineering to build secure, reliable systems, establish standards other teams build against, improve the existing platform, and introduce new technologies and approaches as the environment continues to evolve.

We're particularly interested in engineers who combine strong C#/.NET and Azure experience with deep knowledge of distributed systems, APIs, microservices, and event-driven architecture.

What You'll Do

• Own the architecture and technical direction of the APIs and microservices underpinning the platform, setting standards other teams build against
• Design scalable, secure, and high-performance software systems
• Make high-level architectural decisions and establish coding standards, design patterns, and engineering principles
• Refactor and extend existing systems while designing for long-term flexibility and scalability
• Develop prototypes and proofs-of-concept to evaluate new technologies and reduce implementation risk

Reliability & Engineering Excellence

• Drive best practices across code reviews, CI/CD, automated testing, and observability
• Build and improve monitoring and alerting capabilities to support SLA requirements
• Lead incident response and root-cause analysis for complex production issues
• Help ensure mission-critical, customer-facing applications remain reliable and performant
• Champion security and compliance best practices across the platform

Technical Leadership

• Partner with Product Managers, Architects, and Engineering teams to translate business requirements into technical solutions
• Mentor engineers and help raise engineering standards across the organization
• Drive long-term technical strategy and architectural decision-making
• Evaluate and introduce new technologies, frameworks, and development methodologies
• Work within an AI-driven SDLC environment using tools such as GitHub Copilot

What We're Looking For

• 12+ years of hands-on software engineering experience
• At least 5 years of technical leadership experience
• Advanced experience with C#, .NET, and SQL
• Strong hands-on experience with Azure and cloud-native architecture
• Experience with Azure services such as APIM, Azure SQL, Cosmos DB, and Key Vault
• Deep understanding of RESTful APIs, OAuth2, and OpenAPI
• Strong experience with microservices and event-driven architectures
• Experience with technologies such as Azure Service Bus and Event Hubs
• Strong understanding of containers, caching, Git, DevOps, and CI/CD
• Experience implementing observability using platforms such as Datadog or Grafana
• Ability to troubleshoot complex production systems and perform structured root-cause analysis
• Strong communication, technical leadership, and mentoring skills

Particularly Relevant Experience

Experience in any of the following would be especially valuable:

• Fintech or embedded finance
• Banking-as-a-Service (BaaS) platforms
• High-volume or highly transactional systems
• Financial services APIs and partner integrations
• PCI DSS or SOC 2 environments
• SLA-driven production systems
• Open-source contributions or technical publications

Why This Opportunity?

This role should be particularly compelling for an experienced Principal-level engineer who wants significant technical influence without moving away from hands-on engineering.

You'll own critical architectural decisions behind a high-volume financial platform, solve complex scalability and reliability challenges, set standards other engineering teams build against, and help shape the organization's long-term technical direction.

It's an opportunity to have broad technical influence while remaining close to the technology and building systems directly tied to mission-critical, revenue-generating financial products.