
501 - 1000 employees
Founded 1998
👥 B2C
🔒 Cybersecurity
B2C • Cybersecurity • Software
Mozilla is a non-profit organization dedicated to promoting an open and accessible internet. They are the makers of the popular Firefox browser, which emphasizes user privacy, speed, and control. Mozilla also offers a range of products that focus on internet security and privacy, including Mozilla VPN, Firefox Relay, and Mozilla Monitor. Additionally, the organization is involved in open-source projects, AI innovation, and advocating for digital rights. Mozilla aims to empower users with trustworthy technology and policies that protect privacy, support open-source AI development, and foster accountability for tech companies.
🔥 20 minutes ago
Where this job comes from
Posted on Mozilla's careers page, not through a job board
First seen by Remote Rocketship 20 minutes ago

501 - 1000 employees
Founded 1998
👥 B2C
🔒 Cybersecurity
B2C • Cybersecurity • Software
Mozilla is a non-profit organization dedicated to promoting an open and accessible internet. They are the makers of the popular Firefox browser, which emphasizes user privacy, speed, and control. Mozilla also offers a range of products that focus on internet security and privacy, including Mozilla VPN, Firefox Relay, and Mozilla Monitor. Additionally, the organization is involved in open-source projects, AI innovation, and advocating for digital rights. Mozilla aims to empower users with trustworthy technology and policies that protect privacy, support open-source AI development, and foster accountability for tech companies.
• Design and implement experiments within browser engine subsystems • Investigate how internal data structures and execution behavior affect performance, correctness, and developer-tool interfaces • Evaluate ways to represent and expose browser state efficiently and accurately • Identify tradeoffs including information loss, implementation complexity, and compatibility with dynamic web content • Prototype engine capabilities supporting reliable programmatic interaction with web content • Investigate how document structure, layout, navigation, and event handling affect correctness and performance • Instrument browser behavior and evaluate changes against repeatable tasks • Measure performance and correctness, isolate each change’s effect, and document unsuccessful and successful experiments • Verify that gains hold beyond prototype-development workloads • Profile overhead introduced by new capabilities and pursue measurement-supported improvements • Use AI tools to accelerate coding and analysis, verifying output through debugging, tests, and measurement • Work closely with the team’s technical lead as a hands-on individual contributor
• Deep hands-on expertise in at least one browser engine subsystem, such as DOM and Web APIs, layout and rendering, accessibility, JavaScript runtimes, or networking and process architecture • Strong proficiency in C++ or Rust • Experience navigating a large systems codebase • Practical knowledge of memory ownership, concurrency, object lifetimes, and performance debugging • Ability to build JavaScript and scripting tools needed to exercise and measure work • Demonstrated ability to investigate unfamiliar code, form a precise hypothesis, construct a useful prototype, and interpret the results • Strong understanding of web platform behavior and compatibility • Experience with profiling, tracing, regression tests, or conformance tests • Curiosity about AI agents and willingness to work directly with agent harnesses and coding tools • Contributions to Gecko, Servo, Blink, WebKit, or another browser engine (nice to have) • Experience maintaining an open-source project (nice to have) • Technical leadership in a small team building a new product (nice to have) • Experience with accessibility infrastructure, browser security, profiling, or automated evaluation of agent workflows (nice to have)
• 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)
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