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

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.

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

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.

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.

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.

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 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.

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.

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

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.

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

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 Engineer will design and build APIs, develop user-facing features, mentor other engineers, and ensure high-quality software delivery.

As a Senior Full-Stack Engineer, you will build features across React/TypeScript and Python/Django, shape product outcomes, and collaborate with cross-functional teams to ensure user satisfaction and engineering quality.

Design, build, and maintain scalable web applications using Python and React. Collaborate with teams and ensure application security and performance.

Seeking a Senior Fullstack Engineer with frontend focus in React, TypeScript, and Python. Responsibilities include frontend architecture, API building, and leading frontend standards. Requires 5+ years of experience with strong team collaboration.

Design, build, and maintain resilient full-stack services for distributed financial SaaS systems. Lead end-to-end projects, optimize performance, ensure security and observability, mentor teams, and reduce technical debt.

The Senior Software Engineer will design, develop, and optimize scalable PHP APIs and web applications, collaborating with product and design teams to support product development and implement best coding practices.

The role involves owning the product workflow, building user-facing features, maintaining systems, and collaborating with cross-functional teams. Strong React and Typescript skills are essential.

Lead the development of Coperniq's platform by designing, developing, and maintaining scalable full-stack solutions while collaborating with teams and mentoring juniors.

As a Senior Full Stack Engineer, you'll build interactive customer experiences, manage backend architecture, write well-tested code, and ensure smooth production processes.