Top Senior Full-Stack Engineer Jobs in Denver & Boulder, CO

Build and own complex frontend features using Vue 3 and TypeScript while developing the Python services and APIs that power them. Improve performance, accessibility, testing, CI/CD, and observability; collaborate with product and design; mentor engineers and apply AI-assisted development tools responsibly to accelerate productivity and maintain quality and security.

Design and implement scalable backend services for payment and transaction workflows using Java. Own end-to-end features from data model and APIs to Angular frontends, improve reliability and performance, refactor legacy systems, troubleshoot production issues, and collaborate with product and design. Leverage AI-assisted development tools responsibly and share best practices across the team.

The Senior Full-Stack Engineer will manage client relationships, design integration solutions, and ensure seamless delivery and optimization of technical workflows, while leveraging AI for efficiency.

Lead design and build of an AI-native marketing platform: integrations, multi-agent orchestration, UIs, tooling, analytics, CI/CD, auth/multi-tenancy, and production AI agents to automate marketing workflows and drive adoption across teams.

Build and ship full-stack features for customer-facing Console and Playground, plus internal tools. Design and maintain APIs and backend services, implement accessible performant frontends, translate product requirements into incremental work, and improve code quality through reviews and design discussions.

Develop, maintain and evolve a high-scale US sports trading platform. Build React/TypeScript frontends, backend microservices, optimize SQL and performance, implement CI/CD and automated testing, mentor junior engineers, and collaborate with stakeholders and architecture teams to ensure resilience and integration.

Owner of end-to-end ecommerce features: design, implement, and maintain scalable backend services and performant React/Next.js frontends. Integrate payment gateways and procurement systems (PunchOut), mentor engineers, uphold code quality, and improve platform stability across Node.js, MySQL, and MongoDB.

Design and build agent-powered mission consoles, collaborate with stakeholders to improve user workflows, and maintain agentic workflows for mission outcomes.

As a Senior Software Engineer, you will design and build a cutting-edge identity search platform and implement AI systems for defense applications, working closely with cross-functional teams to enhance user workflows and support national security.

Lead full‑stack design and delivery of customer-facing web experiences (Browse, Navigate, Preview). Own architecture, APIs, data models, rollouts, observability, on‑call readiness, and cross-team alignment, using approved AI-assisted workflows while ensuring technical quality and reliability.

Responsible for leading a team of engineers, supporting product development, identifying technical issues, and ensuring high-quality code delivery in backend systems at scale.

Lead design and implementation of the PSA Liquidity Platform connecting buyers and sellers. Build buyer tooling, matching/ranking engines, and seller experiences. Architect and operate microservices and Kafka-driven systems on Kubernetes/AWS, instrument observability, apply AI tooling across the SDLC, and drive cross-functional delivery from 0-to-1 while owning end-to-end outcomes.

Design, build, and maintain scalable full‑stack web applications using Python (FastAPI/Django/Flask) and Node.js frameworks (Next.js, Nest.js). Build React front ends, architect RESTful APIs, work with SQL/NoSQL databases, implement testing and security best practices, leverage AWS cloud services and AI-assisted development tools, collaborate with product and design, perform code reviews, and mentor junior engineers.

Build developer tooling, documentation, and web experiences for AT Protocol. Develop and operate backend API and identity services, maintain open-source SDKs, support auth and identity management, and ensure production hosting and developer-facing APIs work reliably for third-party builders.

Build and maintain user-facing interactive features and backend APIs. Own architecture, write well-tested code, participate in reviews and standups, ensure production reliability, and create development and deployment standards.

Design, build, and maintain production-grade .NET web applications and APIs on Azure. Own full-stack delivery from data models and SQL to front-end components, CI/CD, testing, and architecture. Collaborate with product and delivery teams, participate in code reviews, and ensure secure, observable, well-tested services.

Build and scale full-stack features for mobile web using React and Python; develop AI-native care-team automation; own production reliability and HIPAA-compliant monitoring; set code quality, testing, and deployment standards; and collaborate with product, data, and clinical teams to translate complex healthcare workflows into practical solutions.

Build end-to-end features, design intuitive interfaces, manage asynchronous backend jobs, and contribute to open-source efforts, while leading project development from concept to monitoring.

The Senior Full Stack Engineer will modernize legacy systems to microservices, maintain .NET applications, optimize SQL databases, and develop frontend interfaces.

The Senior Full Stack Engineer will maintain legacy .NET systems while leading modernization efforts towards a cloud-native microservices architecture, managing both backend and frontend development tasks.

The Senior Full Stack Developer will develop web applications, facilitate Scrum ceremonies, guide agile practices, and drive project goals.

Lead architecture and implementation of consumer-facing features across frontend and backend. Own backend roadmap, design distributed systems, optimize performance and reliability, drive cross-functional delivery, set engineering standards, and mentor teammates while shipping well-tested, scalable features.

Support an agile scrum team to deliver scalable web application features, complete user stories, troubleshoot issues, and mentor developers. Produce technical documentation and architecture-aligned solutions for federal customers while meeting sprint deadlines and compliance requirements.

Senior individual contributor (15+ years) building a greenfield platform. Hands-on full-stack development with .NET/C# backend, Angular frontend, and Azure cloud architecture. Design and implement microservices, APIs, and messaging (Service Bus). Own end-to-end lifecycle from requirements to deployment using CI/CD, GitHub Actions, Terraform, PowerShell, and Azure CLI. Must have practical AI experience embedding tools (Copilot, Claude), agent frameworks, RAG, and AI-driven features within development workflows.

Build and maintain end-to-end features across frontend (React/TypeScript) and backend (Python/FastAPI), design and consume RESTful APIs, write well-tested code, collaborate with product and customers, and iterate quickly based on feedback to support hospital supply chain workflows.