Senior Full Stack Software Engineer

About the Role

We’re hiring a Senior Full Stack Software Engineer to design, build, and scale modern web applications end-to-end. You’ll work across frontend UI, backend services, APIs, asynchronous processing, and data layers—shipping features that are reliable, secure, and built to last.

This is a senior individual contributor role with real autonomy and real impact. You’ll have end-to-end ownership of features and meaningful input into technical decisions, quality standards, and delivery practices working in a remote-first environment.

Core Tech Stack:

• Frontend: React 19, TypeScript, Vite-based React apps, Tailwind CSS, SignalR
• Backend: .NET 9 (C#), Minimal APIs, Entity Framework Core
• Async Processing: RabbitMQ, Redis (for scale-out and caching)
• Data and Storage: PostgreSQL, Amazon S3

What You’ll Do

• Shape the product architecture end-to-end. You’ll design and ship modular .NET services and modern React frontends that stay fast, reliable, and elegant across a wide range of real-world customer environments.
• Own the data foundation. You’ll design high-performance PostgreSQL schemas and craft EF Core queries that serve as the source of truth for business logic, permissions, and RBAC—balancing correctness, clarity, and scale.
• Engineer for performance at scale. You’ll build smart caching layers with Redis and leverage S3 for large artifacts, keeping our Web Gateway lean, responsive, and built to grow.
• Drive technical direction through RFCs. You’ll author and collaborate on design proposals that define data contracts and API boundaries, making our .NET platform and Python-based solver runners work together seamlessly.
• Ship with product and design, not in a silo. You’ll partner closely with product and design to turn real customer problems into thoughtful technical solutions—and deliver them in tight, iterative releases.
• Use AI as a force multiplier (responsibly). You’ll leverage tools like Claude Code and GitHub Copilot/Cursor to move faster and refactor with confidence, while keeping security, quality, and maintainability non-negotiable.
• Hold the quality bar high. You’ll help set the standard through great code reviews, automated testing, and pragmatic engineering practices that keep the codebase a joy to work in.

What We’re Looking For (Required)

• 8+ years of professional software engineering experience delivering production web applications.
• Strong full stack experience shipping user-facing features end-to-end across frontend, backend, and data layers.
• Deep expertise in React and TypeScript, including component architecture, hooks, and performance optimization.
• Experience building and maintaining modern React applications (Vite, Tailwind CSS and client-side data fetching patterns).
• Strong backend experience with C# and modern .NET (.NET 9 or similar), including API design with Minimal APIs and secure development practices.
• Strong experience with PostgreSQL, including schema design, indexing strategies, and query optimization.
• Hands-on experience with Entity Framework Core, including writing efficient queries and managing migrations.
• Experience designing and operating asynchronous workflows (RabbitMQ) and implementing caching strategies (Redis).
• Experience building real-time UI updates using SignalR.
• Experience working with AWS, especially object storage in Amazon S3.
• Solid understanding of authentication or authorization patterns including application-level RBAC (e.g., JWT, OAuth/OIDC concepts).
• Strong written and verbal communication skills, including the ability to collaborate effectively in a remote environment.

Nice to Have (Preferred)

• Experience integrating .NET services with Python-based systems and designing stable data contracts between services or teams.
• Experience with Docker and container orchestration (Kubernetes).
• Observability and performance tooling experience (OpenTelemetry, Application Insights, Datadog, Grafana/Prometheus).
• GraphQL experience (in addition to REST).

• Analytical Aptitude: Possess keen analytical and problem-solving skills, coupled with the capability to understand complex software challenges and collaborate toward viable solutions. 
• Effective Communication: Skilled in distilling technical complexities into comprehensible terms for varied audiences. 
• Adaptive Nature: Resilience and adaptability in the face of an ever-changing tech landscape, with a knack for rapidly integrating new technologies and methodologies. 
• Agile Methodology Experience: An understanding and hands-on experience with agile development methodologies and version control tools. 
• Agility in Tech: Demonstrated adaptability in the fast-paced tech landscape, continually embracing and integrating new technologies and methodologies. 
• Education: While formal education in Computer Science or related fields is a plus, DefconAI values hands-on experience and demonstrable skills above all. Candidates with 6+ years of relevant experience will be considered regardless of their academic pedigree. 
• Continuous Learner: A commitment to perpetually update one's skill set, staying aligned with the latest in technology trends and best practices. 

What We Offer: 

• A fully remote, results-based environment
• Competitive salary, bonus, and equity package
• 100% employer paid, comprehensive health insurance including medical, dental, and vision for you and your family
• Unlimited PTO, with your manager’s approval
• Flexible work environment where you manage your work day
• 14 weeks of fully-paid parental leave

Salary range: $155,000-$215,000. This represents the typical salary range for this position based on experience, skills, and other factors.

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