Feeny
Mozilla

Contract Staff Software Engineer - (Firefox) C++,Storage Encryption at Mozilla (United Kingdom)

Mozilla· United Kingdom·

Role details

Work type
Remote
Level
Staff

Job description

The role

You will help the Firefox DOM LWS team to implement tasks for Storage Encryption everywhere, helping to drive the in-progress project through to completion .

Responsibilities

  • Contributing to delivering Storage Encryption Everywhere in Gecko, which may include tasks such as migrating data between schemas, implementing data storage in PBM and integration testing.
  • Write and pass Web Platform Tests, and add Gecko tests as needed.
  • Work through code review with the relevant Gecko module owners and iterate to landing.
  • Surface and help resolve any specification questions the implementation raises.
  • Shepherd the feature through Nightly, Beta, and Release. Fix correctness, performance issues and regressions.

Definition of done

Ship Storage Encryption Everywhere to release channel. Fix triaged and prioritized issues.

Required qualifications

  • Strong C++.
  • Substantial experience in a browser-engine codebase, ideally Firefox/Gecko.
  • Substantial experience in databases.
  • Familiarity with web standards and Web Platform Tests.
  • Strong debugging and optimization in a multithreaded codebase.
  • Comfort working in the open: public bugs, code review, and upstream landing.

Preferred

  • Prior contributions to Gecko or another major browser engine.
  • Familiarity with the relevant standards body and specification process.

Why work at Mozilla

  • Culture: "Remote-first" company with a strong emphasis on asynchronous work, work-life balance, and global collaboration. The culture is mission-driven, collaborative, and values "responsible participation" — generosity and kindness in communication. mozilla.org
  • Benefits (US employees):
    • Health: 100% premium coverage for medical, dental, and vision for employees and dependents.
    • Mental health: Free therapy and coaching sessions.
    • Time off: 12+ paid holidays, generous vacation and sick leave (accrued from day one), quarterly company-wide wellness days, and your birthday off.
    • Parental leave: 26 weeks paid for childbearing parents, 12 weeks paid for non-childbearing parents.
    • Remote-first: Work from anywhere with a strong stipend for home office setup. mozilla.org
  • Engineering culture: Engineers work on "some of the most interesting challenges facing the internet today — privacy, security, decentralization, access, convenience, compatibility." The Data Organization is at the forefront of using data to guide product decisions while respecting user privacy. mozilla.org
  • Diversity & Inclusion: Mozilla explicitly states it wants to be "a place where everyone can do their best work" and that "diverse perspectives and experiences result in better solutions." They publish transparency data on their progress.
  • Open roles: As of mid-2025, Mozilla has ~90 open positions across engineering (Front-End, Machine Learning, Fullstack), product management, data analytics, marketing, and infrastructure. Key teams hiring include Firefox, Anonym, Fakespot, and Mozilla.ai. greenhouse.io

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