Software Engineer

As a Senior Software Engineer on the Ecosystem Services Team, you’ll build and own back-end systems and the integrations that keep our services running, help maintain and evolve the cloud infrastructure the application runs on, and play an active role in keeping the service reliable and healthy in production. You’ll do this while collaborating closely with frontend engineers, product managers, CloudEng, and UX and design partners to deliver reliable features.

We are looking for engineers who treat the systems they build as their own: people who are comfortable owning a service end to end, from writing the code to verifying it works as intended in production and monitoring its health.

We are hiring for multiple Ecosystem Services Team back-end teams - each solving their own unique challenges to make the web better for everyone. More details about all hiring teams will be shared in the interviews. About Ecosystem Services:

Ecosystem Services builds and operates the back-end platforms that power Mozilla products and services, with a focus on privacy, security, and delivering critical functionality to Firefox and millions of users worldwide.

Our portfolio spans a diverse set of platforms and services. Representative examples include Privacy Services, which provides the APIs and infrastructure behind Mozilla VPN, Relay (email and phone aliasing), and Monitor (data breach detection and remediation); AutoPush, Mozilla’s Web Push platform for securely delivering notifications and real-time updates to Firefox clients; and Remote Settings, Mozilla’s platform for delivering configuration updates to Firefox outside the regular release cycle. Together with many other backend platforms across the organization, these services help deliver secure, reliable experiences to Mozilla users every day.

Our teams own services end-to-end from designing and building distributed systems, to operating them in production, improving reliability, and evolving the cloud infrastructure they run on. We work closely with product, frontend engineering, Cloud Engineering, UX, and design partners to build resilient systems that make the web better for everyone.

We’re hiring backend engineers across multiple Ecosystem Services teams, each tackling different technical challenges while sharing a culture of ownership, collaboration, and operational excellence. More details about the specific teams and domains will be shared during the interview process.

What you’ll do:

• Lead backend development, building and maintaining server-side logic
• Take real ownership of the services you work on: deploy them, operate them, and keep them healthy in production rather than handing them off
• Work closely with our CloudEng Team to maintain and improve production environments, including monitoring and alerting with tools such as OpenTelemetry, Sentry, Prometheus, and Grafana
• Participate in an on-call / off-hours support rotation, triaging and resolving production issues, partnering with CloudEng and support teams to investigate incidents, address bug reports, and keep the application running reliably
• Periodically rotate into a support role, handling releases, dependency updates, and incoming work requests from customer support and other stakeholders
• Thoughtfully apply AI-assisted development tools to move faster and raise quality, while maintaining good judgment about where they fit and where they don’t
• Partner with and support stakeholders (e.g. front-end, platform), ensuring backend systems, APIs, and data contracts meet their needs
• Partner with frontend and cross-functional teams to align on project goals, contribute to API design, and ensure backend systems, APIs, and data contracts meet their needs
• Participate in code reviews to maintain high standards of code quality and system reliability
• Participate in security and privacy reviews, ensuring all data protection measures meet compliance standards, Build and operate scalable full-stack software and AI-powered products for physical operations. Own technically complex areas, define technical strategy, develop backend services, APIs, frontend and potentially mobile experiences, and translate customer problems into measurable outcomes. Lead cross-team initiatives, mentor engineers, participate in technical reviews, and raise engineering quality and velocity. Top Skills: Agentic WorkflowsAIAPIsCursorGoIotJavaScriptLlmsMachine LearningPythonReactRecommendation SystemsTypescript MongoDB

Senior Software Engineer

Yesterday Easy Apply Remote or Hybrid United States Easy Apply 126K-248K Annually Senior level 126K-248K Annually Senior level Big Data * Cloud * Software * Database Build and maintain MongoDB’s distributed database infrastructure for cluster scalability. Design data partitioning, data movement, dynamic scaling, workload execution, and resilient distributed protocols. Solve complex performance and low-latency systems problems, contribute production-quality C++ code, participate in design and code reviews, lead new feature development, and mentor engineers. Top Skills: C++Data PartitioningDistributed SystemsLow-Latency NetworkingMongoDBSystem Observability Unanet

• 4+ years of experience in software development with a strong focus on backend technologies
• Strong professional experience with Python , TypeScript/Node.js, or Rust building back-end services and confidence leading back-end engineering projects.
• Proficiency with PostgreSQL and SQL query optimization, including relational schema design and migrations with a query builder such as Knex
• Hands-on DevOps experience on Google Cloud Platform (GCP), with Docker-based build and deploy pipelines. You are comfortable deploying, operating, and troubleshooting services in the cloud rather than handing that responsibility to someone else
• Hands-on experience with observability and monitoring tooling such as Sentry and Grafana
• A pragmatic commitment to shipping quality work. You care about the quality and reliability of what you ship, you make sensible trade-offs under real constraints, and you consistently move work to and into production.
• Strong engineering judgment. You can navigate ambiguity, weigh trade-offs, and make sound decisions with incomplete information, and you know when to ask for input
• A genuine ownership mindset. You are excited to own a service end to end and have a track record of operating what you build in production, including experience with on-call or off-hours production support
• Experience mentoring junior engineers and driving technical excellence in code quality, testing, and process improvements

Bonus Points for experience with:

• Performance / load testing
• Experience with IaC tools such as Terraform and Kubernetes
• Open-source contributions or personal engineering projects
• Django experience

• Generous performance-based bonus plans to all eligible employees - we share in our success as one team
• Rich medical, dental, and vision coverage
• Generous retirement contributions with 100% immediate vesting (regardless of whether you contribute)
• Quarterly all-company wellness days where everyone takes a pause together
• Country specific holidays plus a day off for your birthday
• One-time home office stipend
• Annual professional development budget
• Quarterly well-being stipend
• Considerable paid parental leave
• Employee referral bonus program
• Other benefits (life/AD&D, disability, EAP, etc. - varies by country)

About Mozilla

Mozilla exists to build the Internet as a public resource accessible to all because we believe that open and free is better than closed and controlled. When you work at Mozilla, you give yourself a chance to make a difference in the lives of Web users everywhere. And you give us a chance to make a difference in your life every single day. Join us to work on the Web as the platform and help create more opportunity and innovation for everyone online., Remote United States 143K-155K Annually Senior level 143K-155K Annually Senior level Enterprise Web * Fintech * Marketing Tech * Software Design, build, test, deploy, monitor, and support scalable enterprise software across the full lifecycle. Evaluate requirements, estimate effort, identify risks, collaborate with Product Management, conduct code and design reviews, and improve architecture and development practices. The role requires full-stack Java and modern front-end experience, API and event-driven integration expertise, database design, incident response, and CI/CD experience with Docker and Kubernetes. Top Skills: Ai-Assisted Development ToolsApache TomcatCi/CdCSSDockerEvent-Driven IntegrationsGitJava 8+JavaScriptJqueryKubernetesMvcReactRestful ApisSQL

What you need to know about the Colorado Tech Scene

With a business-friendly climate and research universities like CU Boulder and Colorado State, Colorado has made a name for itself as a startup ecosystem. The state boasts a skilled workforce and high quality of life thanks to its affordable housing, vibrant cultural scene and unparalleled opportunities for outdoor recreation. Colorado is also home to the National Renewable Energy Laboratory, helping cement its status as a hub for renewable energy innovation.

Key Facts About Colorado Tech

• Number of Tech Workers: 260,000; 8.5% of overall workforce (2024 CompTIA survey)
• Major Tech Employers: Lockheed Martin, Century Link, Comcast, BAE Systems, Level 3
• Key Industries: Software, artificial intelligence, aerospace, e-commerce, fintech, healthtech
• Funding Landscape: $4.9 billion in VC funding in 2024 (Pitchbook)
• Notable Investors: Access Venture Partners, Ridgeline Ventures, Techstars, Blackhorn Ventures
• Research Centers and Universities: Colorado School of Mines, University of Colorado Boulder, University of Denver, Colorado State University, Mesa Laboratory, Space Science Institute, National Center for Atmospheric Research, National Renewable Energy Laboratory, Gottlieb Institute

Mozilla Corporation is the non-profit-backed technology company that has shaped the internet for the better over the last 25 years. We make pioneering brands like Firefox, the privacy-minded web browser. Now, with more than 225 million people around the world using our products each month, we’re shaping the next 25 years of technology and helping to reclaim an internet built for people, not companies. Our work focuses on diverse areas including AI, social media, security and more. And we’re doing this while never losing our focus on our core mission - to make the internet better for people., The Mozilla Corporation is wholly owned by the non-profit 501(c) Mozilla Foundation. This means we aren’t beholden to any shareholders - only to our mission. Along with thousands of volunteer contributors and collaborators all over the world, Mozillians design, build and distribute open-source software that enables people to enjoy the internet on their terms.