Work on Firefox Desktop installs, updates and operating-system integrations, addressing low-level platform-specific challenges on Windows and/or macOS. Requires 3–5 years' software engineering experience, systems-level programming skills (C/C++), collaboration in distributed teams, and familiarity with installation/update systems; Rust and low-level Win32/Cocoa experience are bonuses.

Mozilla seeks a Staff AI & Agentic Systems Engineer to lead architecture and implementation of next-generation multi-agent frameworks and LLM workflows. The role requires 7+ years software engineering experience, 2+ years building production autonomous workflows, strong familiarity with LLM orchestration tools (e.g., LangChain) and experience with Python or Go, distributed systems, and evaluation/benchmarking of agent performance. This is an early-stage, remote position within Mozilla's New Products organization.

Lead technical design and implementation of next-generation agentic systems: build multi-agent frameworks, orchestration layers, and AI developer tooling; integrate and optimize LLMs; establish evaluation/benchmarking and AI-assisted engineering practices. Requires 7+ years software engineering and 2+ years building agentic systems.

Mozilla is hiring a Staff AI & Agentic Systems Engineer to lead architecture and implementation of next-generation multi-agent frameworks, LLM orchestration, evaluation frameworks, and AI developer tooling. Requires 7+ years software engineering experience and 2+ years building production autonomous/agentic systems, with strong skills in Python or Go, distributed backends, LLM tooling (e.g., LangChain), prompt engineering, and RAG/vector DBs. Role is remote within the US and includes published US salary ranges.

Remote role (Spain) to deliver features and architectural improvements across the Add-ons stack (DevHub, Reviewer tools, automated moderation). Requires full‑stack development with React/TypeScript frontends and Python/Django backends, plus work on observability, deployments and incident response on Google Cloud. Senior-level collaboration in an open-source environment.

Work on Firefox Desktop Integrations to develop and improve features related to installation, updates, and OS integration (particularly Windows and macOS). Requires 3+ years as a software engineer, systems-level programming experience on at least one major platform, strong C/C++ skills, and experience collaborating in distributed teams. Rust experience and low-level Windows/macOS API expertise are bonuses.

Responsible for maturing, maintaining, and building features for Mozilla's Internal Developer Infrastructure Platform, including CI/CD, observability, Kubernetes optimization, environment bootstrapping, and cost optimization. Requires 5+ years software engineering experience, technical leadership, proficiency in Python/JavaScript/Go, and strong experience with cloud-native technologies (GCP preferred, AWS acceptable) and tools such as ArgoCD, Grafana, Terraform, Helm, Backstage.

Work on Firefox security architecture and cryptography stack, implement web platform security features, improve reliability and performance of a multi-threaded browser, and collaborate on security initiatives. Required skills include C/C++, security and cryptography knowledge, debugging multi-threaded native applications, and familiarity with Rust and web technologies.

Mozilla is hiring a Senior Software Engineer for Firefox Security to advance Firefox's security architecture and cryptography stack (including cryptographic protocols and WebPKI), design and implement web platform security features, and improve stability, performance, and memory efficiency in a multi-threaded browser. Role requires strong C/C++ proficiency, security fundamentals, debugging skills, and familiarity or interest in Rust. Position is remote (UK) with a stated hiring range of £66,000–£87,000 GBP.

Work on Firefox's security architecture and cryptography stack, including cryptographic protocols, WebPKI, and security-sensitive web APIs. Design and implement web platform security features, improve browser reliability/performance in a multi-threaded native codebase, collaborate across teams on security initiatives, and contribute to technical design and standards-based implementations. Requires strong C/C++ skills, security fundamentals, debugging and systems programming experience; Rust familiarity is a plus.

Work on Firefox security architecture and cryptography stack (cryptographic protocols, WebPKI, security-sensitive web APIs), design and implement web platform security features, improve browser reliability/performance/memory in a multi-threaded native codebase, and collaborate across teams. Requires strong software engineering fundamentals, proficiency in C/C++, familiarity with Rust, and experience debugging cross-platform native applications.

Mozilla is hiring a Senior Software Engineer for Firefox Security to advance Firefox's security architecture and cryptography stack (including WebPKI and PKI evolution), design and implement web platform security features, improve browser reliability/performance, and collaborate on security initiatives. Role expects strong C/C++ skills, familiarity or interest in Rust, multi-threaded and cross-platform debugging, and experience with cryptographic protocols. Salary range for Remote Spain: €58,000–€77,000.

Work on Firefox's security architecture and cryptography stack, design and implement web platform security features, improve browser reliability, performance, and memory efficiency, and collaborate with distributed teams. Role emphasizes C/C++ proficiency, familiarity with Rust, and experience with cryptography and multi-threaded native applications.

Work on Firefox's security architecture and cryptography stack, design and implement web platform security features, and improve browser reliability, performance, and memory efficiency. Role emphasizes C/C++ proficiency, familiarity with Rust, multi-threaded and cross-platform native development, and applied cryptographic/security knowledge while collaborating across distributed teams.

Work on Firefox's security architecture and cryptography stack (including WebPKI and PKI evolution), design and implement web platform security features, and improve browser reliability, performance, and memory usage. Requires strong software engineering skills (C/C++), security fundamentals, debugging of multi-threaded native applications, and familiarity or interest in Rust and web technologies.

Work on Firefox's security architecture and cryptography stack (cryptographic protocols, WebPKI, security-sensitive web APIs); design and implement web platform security features; improve browser reliability, performance, and memory efficiency in a multi-threaded, cross-platform codebase. Requires strong software engineering skills with proficiency in C/C++, familiarity or interest in Rust, debugging, and security fundamentals.

Work on Add-ons stack (DevHub, Reviewer tools, automated moderation) delivering features and architectural improvements; build observability and incident response, improve platform reliability, and help maintain ecosystem safety. Tech stack includes React/TypeScript frontends, Python/Django backend, MySQL, and Google Cloud. Role involves collaboration with engineers, reviewers, product, and community contributors in an open-source environment.

Work on Mozilla Add-ons (AMO) to deliver major features and architectural improvements across DevHub, Reviewer tools and automated moderation pipelines. Responsibilities include full-stack development (React/TypeScript frontends, Django backend, MySQL), building observability and incident response systems on Google Cloud, improving platform reliability, and supporting ecosystem safety and policy compliance. Role is remote (UK) and emphasizes web security practices, open-source collaboration, and cross-functional teamwork.

Work on the Firefox Add-ons stack (DevHub, Reviewer tools, automated moderation) developing full-stack features (React/TypeScript frontend, Django/Python backend, MySQL), improving platform reliability (deployments, monitoring, incident response) on Google Cloud, and contributing to ecosystem safety and observability in an open source, distributed team.

Remote (Canada) senior engineering role on the Mozilla Add-ons (AMO) team focused on DevHub, Reviewer tools and automated moderation. Work includes full-stack development (React/TypeScript frontend, Django/Python backend, MySQL), platform reliability (deployments, monitoring, incident response) on Google Cloud, observability, and ecosystem safety/trust efforts. Hiring ranges listed for Canada (CAD 94,000–139,000/year).