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.

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 design and implement APIs with NodeJS, develop UIs with React, manage data pipelines, and deploy projects on AWS.

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.

The role involves building web applications and APIs for blockchain-based investment products, optimizing front-end performance, and collaborating cross-functionally while maintaining technical excellence.

As a Senior Full-Stack Engineer, lead development of secure AI-driven SaaS applications, focusing on backend architecture, frontend design, and AI integrations. Collaborate with teams to operationalize models and enhance application functionality through cutting-edge AI solutions.

Design, implement, and deliver high-quality, performant frontend interfaces. Collaborate with cross-functional teams, optimize for SEO and user experience, and mentor junior engineers.

The Senior Frontend Engineer will enhance Slate's brand management experience by building UI systems, integrating brand assets, ensuring reliability, writing maintainable code, and mentoring junior engineers.

The Senior Backend Engineer will design and build backend systems for real-time collaboration, focusing on performance, reliability, and team workflows while improving existing infrastructure and contributing to architectural decisions.

The Senior Full Stack Engineer will develop backend services in .NET, build frontend applications in React, and optimize databases while managing cloud-native infrastructures.

As a Senior Full-Stack and Platform Software Engineer at mabl, you will develop features for an AI-powered test automation platform, enhancing user experiences, designing APIs, and optimizing data pipelines while collaborating with cross-functional teams.

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.

Responsible for defining and building user experiences across the full stack, leading both frontend and backend architecture, mentoring engineers, and ensuring product scalability.

As a Full Stack Engineer, you will lead innovative software projects for freight logistics, driving technical vision, mentoring others, and delivering scalable solutions across platforms.

The Senior Full Stack Engineer will design and build core infrastructure for a logistics platform, focusing on backend systems, high-scale CRUD APIs, and real-time, event-driven architectures in a startup environment.

Lead the development of user-facing applications and backend systems, ensure best practices, mentor junior developers, and collaborate with stakeholders on product initiatives.

The Senior Full-Stack Engineer will lead SaaS application development, focusing on backend algorithms, AI integrations, security, and operationalization of models while collaborating with various tech teams.

As a Senior Full Stack Engineer, you'll design and develop custom Shopify applications, integrate solutions, and collaborate with clients to meet their needs.