Senior Software Developer

Role Description: GunBroker.com is seeking a hands-on Senior Software Developer to lead the design and modernization of our API platform while helping shape how our engineering team leverages AI-powered development tools. This role combines technical leadership with active software development and is ideal for an experienced engineer who enjoys designing scalable systems, mentoring developers, and driving modernization initiatives. As a technical leader, you will guide API architecture, lead the migration of legacy .NET applications to modern service-based solutions, establish best practices for AI-assisted software development, and collaborate closely with Product, QA, Data Engineering, and Operations teams. You will influence technical direction, conduct design and code reviews, mentor developers, and ensure high-quality software delivery in a regulated e-commerce environment.

Required Qualifications: 7+ years of experience developing and maintaining production web applications.4+ years of professional experience with C# and .NET technologies.2+ years of technical leadership experience as a Tech Lead, Senior Engineer, or Lead Developer. Proven experience designing and supporting APIs for customers, partners, or internal platforms. Strong understanding of software modernization and incremental migration strategies. Experience implementing comprehensive testing strategies and integrating automated testing into CI/CD pipelines. Daily experience using AI coding assistants or AI development tools with proven validation and quality-control practices. Strong database performance tuning experience, including SQL Server optimization, indexing, and query analysis. Experience troubleshooting production systems, leading incident response efforts, and identifying root causes. Excellent written and verbal communication skills, including technical documentation and design reviews.

Preferred Qualifications: Experience migrating applications from .NET Framework and ASP.NET MVC to modern .NET.Expertise with OpenAPI/Swagger, API gateways, and developer API programs. Knowledge of OAuth 2.0, OpenID Connect, JWT, and modern authentication frameworks. Experience with event-driven architectures, webhooks, Azure Service Bus, or Event Hubs. Experience with Microsoft Azure services including App Service, Functions, Cosmos DB, and containers. Familiarity with Elasticsearch or similar search technologies. Experience building CI/CD pipelines, feature flag implementations, and automated quality controls. Experience creating frameworks, tooling, or governance processes around AI coding agents. Front-end experience with React, Angular, and TypeScript. Experience with additional programming languages such as Go, Rust, or Java. Background in e-commerce, online marketplaces, payments, auctions, or regulated industries. Experience working within compliance frameworks such as SOX, PCI, or similar controls.