Top Senior Backend Engineer Jobs in Denver & Boulder, CO

Build and optimize high-performance backend systems for an xOT security platform using Rust. Participate across development lifecycle, design scalable microservices, integrate third-party devices and data providers, incorporate AI tools, and improve observability and reliability through testing, debugging, and peer review.

Lead backend and full-stack work on the Payments team, building multi-gateway integrations (Stripe, PayPal), payment APIs, and customer payment UIs. Ensure secure, compliant (PCI-DSS) payment flows, reliability, observability, and scalability across AWS/Kubernetes microservices. Partner cross-functionally to design architecture, implement settlement/reconciliation, and maintain high availability.

Design, build, and own backend services for prediction markets across market lifecycle: creation, trading, oracle resolution, settlement, and payouts. Build low-latency, high-throughput microservices and event-driven systems, drive reliability via SLOs and observability, lead incident response, set technical standards, and mentor engineers while partnering cross-functionally to deliver product and compliance-aligned roadmaps.

Design, implement, and evolve complex backend features and architecture. Improve reliability, performance, and security at scale. Mentor engineers, participate in incident response, set backend standards, and integrate agentic AI into production workflows.

Own and evolve the Subscriptions and Payments backend: design APIs, integrate providers, improve reliability and scalability, lead architecture and code reviews, collaborate cross-functionally, and participate in on-call rotations.

Design and implement backend and real-time features in the GitLab monolith for portfolio planning at scale. Optimize PostgreSQL performance, evolve APIs (GraphQL/REST), build capacity planning and work-item hierarchies, create proofs of concept, maintain automated tests, support safe rollouts with feature flags and observability, mentor contributors, and participate in on-call and production troubleshooting.

Maintain and improve GameChanger's backend API server and SDK. Implement API/SDK changes, improve developer ergonomics, optimize performance and scalability, design critical systems, document and mentor teammates, and participate in on-call rotation.

Develop, maintain, and evolve a high-throughput, low-latency US sports trading platform. Build scalable microservices on GCP with Kubernetes using Go or Rust. Ensure resilience during peak events, contribute to architecture, mentor junior engineers, collaborate with stakeholders, and adopt CI/CD, IaaS, concurrency debugging, and in-house AI technologies to deliver reliable global services.

Develop, test, and improve the OT Security Platform as part of the Microsegmentation Product Team, ensuring high-quality software and architecture.

Design and implement secure, scalable backend services for speech inference and audio processing. Optimize networking, transcoding, latency, memory, and distributed compute orchestration. Measure and improve system performance, debug complex networking/scheduling/HPC issues, customize services for customers, and partner with Product to deliver features end-to-end.

Design, build, and improve scalable backend systems that collect hard-to-access OSINT; build pipelines and ETL for messy data; collaborate with product and mission teams; mentor engineers and ensure reliable data delivery for DoD workflows.

As a Senior Software Engineer, you'll own backend systems, mentor team members, and collaborate with product and design to build user-focused solutions.

Build reliable AI-powered, agentic backend systems to remove friction across the software development lifecycle. Design multi-step orchestration, safety checks, and evaluation tooling; apply distributed-systems judgment; work across GitLab codebases and with a distributed team to productionize solutions that may become customer-facing.

Lead backend development for Dragos' OT security platform: design and implement high-performance systems in Rust, optimize architectures, participate across the development lifecycle, integrate databases and third-party data providers, incorporate AI tools, mentor senior engineers, and drive cross-team architectural decisions.

Lead design and delivery of a reliability platform for production systems. Own quarterly goals, guide engineers through ambiguity, collaborate with PM/design/analytics, monitor and operate services (on-call), set quality and code standards, and mentor teammates. Integrate AI/LLM tooling to improve automation, debugging, and service health.

Lead delivery for the Batch Infrastructure team: design, build, and operate reliable, scalable compute platforms for scheduled and on-demand batch workloads. Collaborate with product/design/analytics, define technical plans, ensure availability (monitoring/on-call), set code and design standards, and mentor engineers to improve delivery and quality.

Build, operate, and extend data platform and application-layer services enabling secure, self-service data applications at scale. Implement provisioning, CI/CD, access control, integrations, observability, automation, and incident response while contributing to semantic layer and AI-ready tooling roadmaps.

The Senior Software Engineer will lead and support a team in developing reliable and scalable backend systems, collaborating on product development, and improving infrastructure for secure communication between services.

Design, build, and maintain high-performance backend services for dynamic video packaging, DRM-protected manifest generation (HLS/MPEG-DASH), and server-side ad insertion at scale. Troubleshoot production incidents, lead root cause analysis, and expand observability. Integrate DRM (Widevine, FairPlay, PlayReady), optimize monetization workflows, and apply AI-driven tooling to automate testing and predict performance degradation.

Design and build tooling, workflows, and guidance to make GitLab easier to deploy, validate, and operate across cloud-native, self-managed, and ephemeral environments. Shape deployment architecture, topology, scaling principles, and platform contracts while collaborating with application, infrastructure, and delivery teams.

The role involves designing and expanding backend systems, mentoring engineers, and executing technical strategies to modernize architecture and improve system performance.

Design, build, and maintain scalable backend services and APIs for commerce workflows using Python/Django. Improve reliability, performance, and observability, operate AWS deployments, work with PostgreSQL and event-driven architectures (SNS/SQS), modernize legacy systems, and support CI/CD, testing, and production troubleshooting.

Design, build, and operate backend Go services and smart contracts that mint, burn, bridge, and reconcile wrapped assets across multiple chains. Own end-to-end delivery from smart contract deployment through API design, SLOs, and production rollout. Drive asset migration pipeline improvements, run on-call operations, build observability and runbooks, and mentor junior engineers.

Design, build, test, and maintain backend services and APIs powering the insurance platform. Integrate payments, documents, and data providers, improve system stability, performance, and scalability, mentor team members, and participate in architectural decisions and agile ceremonies.

As a Senior Backend Engineer at DuckDuckGo, you'll lead backend projects, mentor engineers, and develop AI-enhanced features for the company's privacy-centric product line.