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

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.

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.

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.

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.

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.

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.

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.

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

Build and scale full-stack web applications using TypeScript and React, manage CI/CD and cloud infrastructure with IaC, automate deployments, collaborate cross-functionally, use AI tools to accelerate delivery, and uphold code quality, reliability, and security.

Lead design and implementation of secure, cloud-first enterprise architectures focused on IAM and Zero Trust. Develop full-stack applications, optimize app/database performance, integrate secure APIs, collaborate with engineering and DevSecOps, assess risks and tradeoffs, drive identity modernization and cloud modernization, and mentor software developers while promoting security and engineering best practices.

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.

Build and maintain core platform features, expand Infisical PKI/SSH/KMS product lines, collaborate with CTO and engineers, communicate with enterprise customers, and prototype AI applications for secrets management.

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.

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

Design, develop, test, and maintain full-stack applications using Angular, TypeScript, Node.js/NestJS; build and integrate RESTful APIs; support ETL and data processing with Python/PySpark; collaborate in SAFe Agile with architects, QA, and DevOps; maintain CI/CD, documentation, and federal compliance; mentor developers and help modernize large-scale federal health IT systems.

As an Operations Reliability Engineer, design and implement automations to eliminate manual tasks in brokerage operations, focusing on efficiency and reliability while collaborating with cross-functional 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.

As a Senior Fullstack Developer, you will build and maintain moderation and user-safety applications for Bluesky's Trust & Safety team, collaborating with product teams and improving tools based on user feedback.

As a Senior Full Stack Engineer, you'll own major features, build across the stack, influence architecture, and ensure security while working closely with a small team.