Principal Software Engineer

About the role

Principal Software Engineer

About the Opportunity

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

Architecture & Development

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

Large-scale distributed architectures

AI-assisted software development

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.