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

Build and launch scalable fullstack web applications and APIs for Affirm’s Ads Platform. Collaborate with product, design, analytics, and engineering partners to break projects into deliverable phases, make technical trade-offs, write tested and extensible code, monitor service metrics, support on-call operations, review code, and participate in team development and interviews.

Build and ship full-stack web and mobile experiences across Affirm’s consumer products. Break down projects, collaborate with product, design, and analytics teams, develop scalable APIs, write well-tested code, monitor service health, participate in on-call support, review code, and contribute to engineering growth and interviewing.

Lead design and delivery of full-stack basketball scoring, statistics, and postgame features. Build scalable backend services and APIs with TypeScript and Node.js, develop React web experiences, support iOS and Android products, and make architectural decisions. Collaborate across product, design, and engineering teams, ensure code quality and system reliability, mentor peers, and contribute to technical standards and tools.

Lead the architecture and delivery of GitLab’s data products, including near-real-time data ingestion, knowledge graph integrations, data marketplaces, observability, and data-sharing APIs. Translate ambiguous 0-to-1 initiatives into roadmaps, resolve cross-team dependencies, ensure operational readiness across deployment surfaces, and mentor engineers. The role requires deep full-stack expertise, technical leadership, and experience with AI-powered orchestration and multi-tenant SaaS systems.

Develop and support software, automation tools, dashboards, and alarms for cloud infrastructure, cost attribution, and cloud efficiency. Collaborate with cross-functional teams and senior engineers to design reliable systems, APIs, databases, tests, and AI agents. Contribute to architecture and automation strategies while maintaining strong security, communication, and delivery practices.

Build backend-focused Java/Kotlin APIs and data-driven product features, while contributing to React dashboards and workflows. Design scalable systems, participate in architecture and code reviews, troubleshoot production issues using observability tools, and collaborate with data, reporting, design, and product teams to launch emerging products.

Develop fullstack web applications, enhance platform performance, collaborate on high-impact opportunities, and ensure stable, scalable solutions. Engage in rapid iterations and be a committed team player.

Lead software engineering teams developing, integrating, deploying, and maintaining full-stack mission applications for DoD and intelligence customers. Build prototypes and high-performance user interfaces, integrate APIs and independent capabilities, collaborate with military and government operators, and conduct deployment, field testing, and troubleshooting in secure operational environments. Manage customer relationships while ensuring software quality, reliability, and performance.

Build and maintain scalable e-commerce and marketplace features across Node.js, React, MySQL, and MongoDB. Own complex features end to end, design backend services and APIs, integrate PunchOut procurement systems, improve platform security and reliability, conduct code reviews, and mentor engineers. The role requires strong full-stack JavaScript and TypeScript expertise, e-commerce domain experience, and the ability to work autonomously on high-volume transactional software.

Volunteer Principal Full Stack Engineer to lead and contribute across frontend and backend (React/React Native, Node.js, MongoDB). Own feature development, mentor engineers, collaborate with product/design, ship scalable code, and support CI processes. Must commit 4+ hours weekly and attend a weekly standup; first task includes launching a fundraising campaign.

Build and improve the ElevenAPI developer dashboard, onboarding flows, API key creation, integrations, and self-serve subscription experiences. Own features end to end across frontend and backend, from discovery and design through deployment and iteration. Use developer feedback, product data, and experiments to improve activation and successful integrations while collaborating with a remote team.

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.

Join a small engineering team as a hands-on full stack developer. Accelerate frontend delivery, then take on backend services, infrastructure, and core capabilities. Own features from design through release and operational stability, collaborate with customer-facing engineers and founders, and promote effective AI-assisted development practices. The role requires strong backend-oriented full stack skills, product-launch experience, system design judgment, self-direction, and periodic travel to a California office.

Build and own an ads engine end to end, including data pipelines, agent tools, user interfaces, ad generation, localization, launching, and performance learning. The role requires direct user engagement, product judgment, rapid experimentation, and full-stack engineering. You will independently define product direction, ship initial versions, and potentially develop competitive intelligence briefs or new ad formats using LLMs and agent technologies.

Build and scale full-stack software supporting emergency housing, nonprofit partners, housing supply, and fundraising. Collaborate with product, design, data, and operations teams to deliver program features, break initiatives into milestones, use research and data to guide improvements, and work within large codebases. The role requires designing APIs and services, delivering reliable software incrementally, and adapting quickly to changing global needs.

Owns incident triage and resolution across the member app, clinical Care Hub, internal tools, and data pipelines. Responsibilities include reproducing issues, investigating logs and code, shipping durable fixes, prioritizing technical backlogs, writing runbooks, creating alerts and automations, and communicating with members and care teams. The role requires careful handling of protected health information and close collaboration within a remote engineering team.

Build end-to-end features for marketing and growth SaaS products, including interactive user interfaces, CRUD applications, backend APIs, analytics platforms, observability tools, and ML integrations. Collaborate with customers, designers, product managers, and ML engineers to translate real-world needs into intuitive products and experiments. Independently architect frontend systems while contributing to backend data models and API design.

Develop backend services, APIs, cloud-native applications, and mission-specific software for satellite operations. Build full-stack features using Python, AWS, React, TypeScript, and GraphQL; design distributed systems; manage containerized and serverless architectures; automate infrastructure and deployments; troubleshoot production issues; and improve system scalability, security, reliability, observability, and performance while collaborating with government customers and cross-functional teams.

Leads the design, development, testing, deployment, and technical direction of scalable AWS backend solutions for assessment scoring systems. Builds Node.js and TypeScript APIs, microservices, data pipelines, and serverless applications; resolves production issues; ensures engineering quality and data accuracy; and mentors junior engineers. Partners with product, business, and psychometrics stakeholders on requirements, roadmaps, and delivery. Promotes DevOps, testing, documentation, responsible AI-assisted development, and continuous improvement.

Develop and maintain modern full-stack applications using React, TypeScript, Python, and API frameworks. Responsibilities include technical planning, architecture, testing, deployment, documentation, performance, security, CI/CD, and production support. The role integrates generative AI, LLMs, RAG, intelligent search, AI agents, and workflow automation into enterprise applications. It also involves collaborating with product, UX, architecture, data, and engineering teams; conducting code reviews; mentoring junior engineers; and evaluating emerging technologies.

Build and deploy full-stack enterprise product solutions for ElevenCreative customers. Work directly with enterprise clients to understand requirements, present solutions, and decide between bespoke integrations and broadly useful product improvements. Develop integrations, APIs, authentication, SSO, access controls, and other enterprise functionality while shipping independently with minimal direction. Experience with localization, TMS integrations, marketing tools, or adtech is advantageous.

Lead design, development, testing, and deployment of cloud-native full‑stack applications and microservices. Provide technical leadership, mentor engineers, implement CI/CD and automated tests, and drive modernization using GCP or similar cloud platforms, containers, and enterprise security best practices.

Designs, develops, and deploys enterprise applications using Java, Spring Boot, microservices, REST APIs, cloud services, databases, DevOps tools, and Angular or React. The role also involves AI exposure with Python, LangChain, and LangGraph, along with application security, monitoring, performance, deployment, and collaboration with project teams. The position is onsite in McLean, Virginia.

Design, implement, and optimize full-stack solutions. Collaborate with cross-functional teams, participate in code reviews, analyze and improve system performance, and stay current with industry technologies.

Own backend services and frontend experiences across signup, onboarding, verification, activation, checkout, and customer lifecycle management. Build event-driven systems, integrate identity and risk providers, handle sensitive financial data, run experiments, and analyze funnels using SQL and Snowflake. The role also involves evaluating AI-generated code, analysis, and customer messaging while collaborating with Product, Data, and Risk in an ambiguous, high-ownership environment.