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

Build and own end-to-end full-stack features across backend services and user-facing applications. Contribute to system design, reliability, performance, observability, and engineering practices while collaborating with product and design.

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.

Lead design and implementation of the PSA Liquidity Platform connecting buyers and sellers. Build buyer tooling, matching/ranking engines, and seller experiences. Architect and operate microservices and Kafka-driven systems on Kubernetes/AWS, instrument observability, apply AI tooling across the SDLC, and drive cross-functional delivery from 0-to-1 while owning end-to-end outcomes.

Build and maintain frontend and backend platform components using Python and TypeScript, support the open-source SDK, collaborate with engineering and AI teams, write tests and CI-friendly code, fix bugs, and participate in code reviews and mentorship.

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.

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.

Volunteer Principal Full Stack Engineer to lead and contribute across frontend and backend (React/React Native, Node.js, MongoDB). Own feature development, mentor engineers, collaborate with product/design, ship scalable code, and support CI processes. Must commit 4+ hours weekly and attend a weekly standup; first task includes launching a fundraising campaign.

Design and implement backend features in Go, build data pipelines and REST APIs, work with PostgreSQL and AWS, contribute to scalable system design, and optionally develop React.js user-facing features while collaborating in a fast-paced AI-focused startup.

Build and maintain end-to-end features across backend (Node.js/TypeScript, Python) and frontend (React/TypeScript). Model Postgres schemas, integrate queues (QStash/Upstash), deploy on Cloudflare edge, write tests, enforce CI/CD, and harden systems for security and performance in regulated environments.

Build end-to-end user features under senior guidance: implement REST endpoints in Node.js/TypeScript, microservices in Python, maintain PostgreSQL schemas, process background jobs with QStash/Upstash, deploy to Cloudflare Workers/Pages/R2, write tests, and collaborate with product/design on React UI components.

Design, build and maintain Microsoft Cloud applications using Power Apps/Pages and Azure services. Implement Entra ID authentication, Azure Functions/App Services, Logic Apps and Blob storage. Create Azure Data Factory pipelines and APIs (REST/GraphQL), integrate external services and LLM data pipelines, and ensure performance, security, and scalability while collaborating with customers to turn requirements into streamlined apps.

The Full-stack Engineer will build and own features for Hercules' AI-driven applications, including the AI Agent and App Builder, focusing on clean code, SaaS functionalities, and system design within a team-centric environment.

The Staff/Principal Full Stack Engineer will design and build core web applications, backend services, and integrate AI capabilities for healthcare-focused operational tools.

Full Stack/Frontend Developer to build responsive, accessible, performant UIs using React or Vue, integrate with Java/Spring backends, implement component-based architectures, consume REST APIs, write frontend tests, use modern tooling (Webpack/Vite/Babel/ESLint), and work in Agile teams.