Staff Software Engineer-Bug Burndown

Thunderbird; Canada; Remote; GBP 62,000 - 104,000; Full time

Benefits offered by this job

Flexible remote work environment

Parental leave and family support

Professional development reimbursement

Up-to-date work setup

Job summary

Mozilla Corporation is seeking a Contract Staff Software Engineer to help reduce Firefox WebCompat bug backlog by diagnosing and triaging site-breakage reports, writing interventions, and landing simple fixes with AI assistance.

You will work with the Firefox team, leveraging HTML/CSS/JS and browser devtools to diagnose issues, reproduce breakage, and ship fixes while benefiting from a mentorship-driven culture and flexible remote work across multiple countries.

Qualifications

• Solid web development with HTML, CSS and JavaScript and comfort debugging real-world site breakage.
• Fluent with browser devtools and cross-browser diagnosis.
• Comfortable using AI tooling to speed up diagnosis and fixes.

Responsibilities

• Finish diagnosing, or verify the diagnosis of, long-tail WebCompat bugs.
• Write WebCompat interventions where appropriate.
• Write simple fixes (AI-assisted) and land them.
• Reproduce and triage incoming site-breakage reports.

Skills

HTML

CSS

JavaScript

Browser devtools

AI tooling

Job description

Contract Staff Software Engineer-Bug Burndown

at Mozilla Corporation

Team: Firefox

Locations: Remote Canada; Remote Germany; Remote UK

You will help reduce Firefox’s WebCompat bug backlog by finishing or verifying the diagnosis of the long tail of site-breakage bugs, and by writing interventions or simple fixes (often with AI assistance). You turn a large queue of reported breakages into diagnosed, actionable, or fixed bugs.

Responsibilities

• Finish diagnosing, or verify the diagnosis of, long-tail WebCompat bugs.
• Write WebCompat interventions where appropriate.
• Write simple fixes (AI-assisted) and land them.
• Reproduce and triage incoming site-breakage reports.

Required Qualifications

• Solid web development (HTML, CSS, JavaScript) and comfort debugging real-world site breakage.
• Fluent with browser devtools and cross-browser diagnosis.
• Comfortable using AI tooling to speed up diagnosis and fixes.

Preferred

• Gecko knowledge is a strong plus (but can be taught).
• Prior WebCompat or web-standards experience.
• Remote Canada; Remote Germany; Remote UK

Why Mozilla?

At Mozilla, we’re serving humanity—by maintaining a safe, open internet—while also helping the individual humans employed here to reach their personal and professional goals. With a relatively small team serving hundreds of millions of people, a culture of exploration, and a commitment to mentorship, opportunities abound to learn and grow at Mozilla.

Our values drive our actions

• Purpose is built into our work, with our mission driving every decision
• We challenge assumptions, the status quo, ourselves, and each other
• We are transparent: in our code, our business partnerships, and our everyday interactions
• We seek out people from diverse backgrounds and with perspectives different from our own
• We pair purpose with performance and put people ahead of profit

Our impact is global

• 1000+ paid staff from over 30 countries
• Thousands of volunteer contributors across six continents
• 2 global offices: Berlin and Toronto
• 9 coworking space locations: San Francisco, San Mateo, London, Paris, Portland, Tulsa, Vancouver, Chicago, and Bellevue
• Hundreds of home offices globally

Our benefits are world-class

• Flexible work environment (majority of Mozillians work remotely)
• Industry-leading paid parental leave (up to 26 weeks of fully paid leave for childbearing parents and up to 12 weeks for non-childbearing parents)
• Reimbursement for professional development (up to $3,000/year)
• A work setup including the latest hardware and software of your choice