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

Lead design, build, and deploy full-stack software for DoD/IC missions. Rapidly prototype MVPs, integrate systems and APIs, deliver high-performance frontends, collaborate with users, and deploy/test in secure operational environments.

Build and grow Homebot applications, services, and APIs end-to-end. Use AI tooling to rapidly deliver features, create AI-driven workflows, and ship maintainable, well-tested, scalable code. Collaborate with product, design, and engineering, and instrument systems with monitoring, logging, tracing, and analytics.

Modernize a large fintech platform by building NestJS services and Next.js UIs, migrate transactional data to relational schemas, write comprehensive tests, identify and fix legacy problems, design scalable solutions that coexist with legacy systems, and use AI tooling responsibly to increase engineering velocity.

The Full Stack Engineer will develop features for a dynamic web application, collaborate with team members, enhance performance, and improve automated tests.

As a Fullstack Engineer, you'll design, build, and operate web applications, collaborating with product teams and mentoring peers while ensuring best practices in coding and system architecture.

The Full-Stack Engineer will build and maintain applications, own features end-to-end, contribute to system design, and collaborate closely with product and design teams while improving system reliability and performance.

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, develop, and maintain front-end and back-end components of containerized microservices for defense/intelligence applications. Collaborate on APIs or message-bus architectures, use CI/CD and Agile practices, and operate in a distributed team environment while meeting security requirements.

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.

Build and own end-to-end full-stack systems for AI-powered agentic trading across web and React Native mobile. Implement real-time, low-latency UIs and Go backend services, integrate streaming AI/ML features and market data, drive architecture and code quality, and collaborate with AI/ML, design, and product teams to ship production-ready features used by millions.

As a Senior Software Engineer, you'll implement collaboration features, support team architecture, work across tech stacks, and improve developer experience.

The Staff Software Engineer will lead full-stack initiatives, improve system quality, drive technical direction, and mentor peers in a collaborative environment.

As a Fullstack Software Engineer, you'll design, develop, and maintain scalable frontend and backend systems while collaborating across teams.

Lead design and build of an AI-native marketing platform: integrations, multi-agent orchestration, UIs, tooling, analytics, CI/CD, auth/multi-tenancy, and production AI agents to automate marketing workflows and drive adoption across teams.

Build and ship full-stack features for customer-facing Console and Playground, plus internal tools. Design and maintain APIs and backend services, implement accessible performant frontends, translate product requirements into incremental work, and improve code quality through reviews and design discussions.

The Software Engineer will design, maintain, and develop web solutions, focusing on real-time data and integrating geospatial data for front-end and back-end applications. Requires ownership of the software lifecycle, using modern frameworks and tools.

Secure customer-facing products, APIs, and internal services through threat modeling, architecture and code reviews. Remediate vulnerabilities by coding fixes in Python/Go/JS/TS. Build and manage SAST/DAST/SCA security pipelines in CI/CD. Configure WAFs, API gateways, and bot protection. Provide secure coding guidance, run bug bounty triage, and support compliance (SOC 2, ISO 27001, GDPR).

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 the engineering effort for a seed-stage dating app: audit and improve the existing codebase, design and build v2 (mobile and backend), implement real-time features, define engineering standards, scale infrastructure on AWS, and, after fundraising, hire and mentor a small team while shaping the technical roadmap.

Lead architecture, modernization, and development of Group Insurance applications. Modernize mainframe monoliths into Java microservices and micro-frontends on cloud, mentor distributed Agile teams, collaborate with enterprise architecture, product owners and infrastructure, and enable test automation and integrations. Approximately 10% domestic travel.

Develop, maintain and evolve a high-scale US sports trading platform. Build React/TypeScript frontends, backend microservices, optimize SQL and performance, implement CI/CD and automated testing, mentor junior engineers, and collaborate with stakeholders and architecture teams to ensure resilience and integration.

Lead frontend-leaning full-stack implementation work for carrier and enterprise integrations: architect reusable UI and API layers, author RFCs, guide technical delivery, enforce testing and security best practices, and partner with cross-functional teams to scope and ship production integrations.

The Fullstack Engineer will design, develop, and improve software for public safety agencies, adhering to quality, security, and architecture standards while collaborating with teams.

Build and maintain internal web tools supporting ML workflows. Develop backend services, frontend features, and deployments; participate in on-call rotations and code reviews; collaborate with partner teams to scale ML tooling and improve authentication and deployment processes.

Develop and maintain front-end and back-end components of AI-driven products, collaborating with teams to enhance user experience and build proof of concept products.