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

As a Senior Fullstack Engineer, you'll contribute to backend development for Toast's New Ventures team, collaborating on architecture and launching MVPs while addressing unmet operator needs.

The Senior Fullstack Engineer will build and manage enterprise authentication systems, improve user session management, ensure security compliance, and support internal API usage across services, while enhancing performance and reliability.

The Senior Full Stack Engineer will develop and maintain features for Engrain's products, integrate AI tools, mentor junior staff, and support DevOps practices.

The Senior Full Stack Engineer develops and maintains the US Sports platform, coaches junior engineers, collaborates with stakeholders, and ensures high system performance under demand.

Design, build, deploy, and optimize scalable full-stack applications integrating databases, APIs, and AI/LLM workflows. Lead architecture, CI/CD (ArgoCD, GitLab), Airflow pipelines, and collaborate cross-functionally to deliver production-grade fintech solutions.

Lead and modernize core Laravel/PHP backend systems and high-performance React/TypeScript frontends. Architect integrations (MLS/RETS/RESO), improve video processing and media delivery, strengthen CI/CD and Docker deployments on AWS/Rackspace, introduce AI-driven automation, and provide senior technical leadership and mentorship.

Drive feature development and architectural decisions across frontend and backend systems, mentor junior engineers, identify tech debt, and collaborate across departments.

The Senior Full-Stack Developer will design, build, and maintain AIO Logic's cloud-based AXIS platform, utilizing React and Java/Spring Boot to deliver software solutions for complex financial workflows, collaborating with cross-functional teams, and mentoring junior developers.

Join the Entefy team as a Senior Full Stack Engineer to build a scalable full stack application enhancing digital interaction for global clients.

The Senior Full-Stack Engineer will develop new features and improve existing functionality, collaborate with the product team, and resolve bugs while influencing architectural decisions.

As a Senior Fullstack Engineer, you'll develop a no-code platform, build UIs and backend services, and improve conversation analysis workflows using AI technologies.

The Senior Fullstack Engineer will lead projects, mentor engineers, and build user-facing SaaS products using React, TypeScript, Node.js, GraphQL, and MongoDB, focusing on team collaboration and effective trade-off decision-making.

As a Fullstack AI Engineer, you will design and develop scalable applications, integrating AI solutions and collaborating with the CTO in a startup environment.

As a Senior Full Stack Engineer, you will design and build cloud-native applications, focus on performance and scalability, and ensure platform stability while collaborating with product teams.

As a Senior Full Stack Engineer, you will design and implement systems and tools to support Sales and Customer Success, improving efficiency and user experience while ensuring system reliability and scalability.

The Senior Full Stack Engineer will design and implement APIs with NodeJS, develop UIs with React, manage data pipelines, and deploy projects on AWS.

As a Senior Full Stack Engineer, you will design and develop trading platforms, create high-performance UIs, and mentor client engineering teams.

As a Senior Full Stack Engineer, you will design and implement features, maintain systems, and ensure performance in a fintech environment, collaborating with cross-functional teams.

As a Senior Full Stack Engineer, you'll architect and build accessible web applications, lead end-to-end solutions, and enhance team efficiency through innovative practices at a remote digital agency.

Design, develop, and deliver fullstack web solutions, optimize platforms, mentor engineers, and manage product features from ideation to launch.

The Senior Fullstack Engineer will build fullstack features for Real User Monitoring, working with backend services, APIs, and frontend visuals. Responsibilities include designing data ingestion systems, optimizing queries, and collaborating with SDK engineers to enhance user experience. Candidates should have strong backend and frontend expertise, particularly in high-volume data systems.

The Senior Full-Stack Engineer at SafeRide Health will develop and maintain healthcare applications, ensuring high performance and security while collaborating with cross-functional teams in an agile setting.

The Senior Full-Stack Engineer will develop claims monitoring tools and backend services, collaborate with other engineers, and influence the product architecture in a health insurance startup.

As a Senior Full-Stack Engineer, you will develop and improve features for a digital clinic, ensuring quality patient care and software reliability across the stack including React and NestJS.

The Senior Full Stack Developer will build end-to-end solutions, collaborate in a remote environment, and write technical documentation. The role requires expertise in Ruby on Rails and various programming paradigms.