Full Stack .NET Engineer

Biller Genie•Orlando, FL

4d•Onsite

About The Position

We are seeking experienced AI-enabled .NET full-stack engineers who can quickly understand our existing codebase and significantly contribute to the development of complex, innovative solutions in our fast-paced fintech environment. As a key member of our engineering team, you will take ownership of significant features, driving them from conception to deployment. We need a versatile 'Swiss Army Knife'—a engineer who is comfortable across the entire SDLC, from architectural design and implementation to testing and deployment. Your experience and expertise will be vital in delivering high-quality, robust solutions. Join our growing team and make a substantial impact on our platform! Recently ranked #482 on the Inc. 5000 fastest growing companies in the United States, Biller Genie is an award-winning B2B SaaS platform that is entering the Belfast market with ambitious plans to scale our team rapidly, with over 100 hires planned through 2028. We are an AI-enabled engineering team, and we believe the future is about empowering engineers with the latest tools, building through custom skills, agents, and harnesses, and we are looking for people who embrace AI, are excited about the future, and want to help shape the way we embed AI tooling throughout our developer experience.

Requirements

BSc or MSc in Computer Science / related qualification OR commercial experience of developing in C#, Java or other OO programming languages
Minimum 3 years of hands-on commercial experience programming on the .NET platform using C#, including ASP.NET (MVC)
Experience with Design Patterns, refactoring, OO Design and related areas
Practical hands-on experience with AI coding assistants and agentic engineering workflows, and a genuine appetite to work primarily through agents — owning architecture, review, and quality rather than typing every line
Exposure to building web services using Web API
An understanding of database design and development
Hands-on experience with HTML, JavaScript, CSS including jQuery
Strong attention to detail and work ethic
Strong analytical and problem-solving skills
Excellent communication (both written and verbal) and interpersonal skills
Experience of cloud technologies such as Azure/AWS/GCP
Previous experience working with source control tools (TFS, SVN, or GIT)

Nice To Haves

Experience with Azure Functions and Queues
Experience building custom agent skills, harnesses, MCP servers, or prompt libraries
Experience defining evals, guardrails, or review practices for AI-generated code
Experience in testing methodologies
Experience of LEAN software development practices
Knowledge of CI/CD systems and implementation practices
Hands-on experience with front-end frameworks such as Bootstrap
Knowledge on .NET Core and Entity framework Code First migrations
Proficient with Claude or Claude Code
Experience in Financial services industry

Responsibilities

Design & build future-proof solutions to support growing business needs while thoroughly considering the system impact
Work closely with our senior engineers to develop solutions from idea to implementation by estimating, planning, tracking and managing progress, risks, and dependencies.
Gather and refine requirements, and release software in a timely fashion
Be adaptive and strike a good balance between speed and efficiency
Work with our technical support team to identify, reproduce, and remediate bug tickets
Build and deliver features through agentic tooling — designing, iterating on, and improving our custom skills, agents, and harnesses as part of the work
Contribute prompts, skills, and workflow improvements back to the team so our AI-enabled developer experience compounds
Perform other duties required by Management