Jobs / United States / mozilla

mozilla

Contract Software Engineer - DOM Core Firefox/Gecko

Location unlisted Posted today

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Sponsorship verdict

Sponsorship possible

One solid signal, not two. Worth applying, and worth asking about sponsorship early.

  • Employer is on a government sponsor recordThe US Department of Labor certified 2 H-1B/E-3 labor condition applications for this employer between Oct 2025 and Jun 2026 (latest Jun 2026) — the step every H-1B hire needs first.
  • The posting doesn’t mention sponsorshipSilence isn’t a refusal — ask the recruiter before investing much time.
  • No salary bar for this routeH-1B has no fixed salary bar: the employer must pay at least the prevailing wage for the role and area.
  • What mozilla paid sponsored hires in similar roles1 certified filing for “Senior Director of Machine Learning, Firefox” (Computer and Information Systems Managers) in WA: $413k–$413k, median $413k.
  • Confirmed live todayWhen a source last listed this job as open.
Details and sources
Employer is on a government sponsor record
The US Department of Labor certified 2 H-1B/E-3 labor condition applications for this employer between Oct 2025 and Jun 2026 (latest Jun 2026) — the step every H-1B hire needs first. Source: LCA disclosure data (US Department of Labor (OFLC)).
No salary bar for this route
H-1B has no fixed salary bar: the employer must pay at least the prevailing wage for the role and area. Cap-subject employers enter a lottery weighted by wage level. Source: https://www.federalregister.gov/documents/2025/12/29/2025-23853/weighted-selection-process-for-registrants-and-petitioners-seeking-to-file-cap-subject-h-1b, rules effective 2026-02-27.
What mozilla paid sponsored hires in similar roles
1 certified filing for “Senior Director of Machine Learning, Firefox” (Computer and Information Systems Managers) in WA: $413k–$413k, median $413k. Most were filed at wage level IV (100%) — 4 lottery entries, ≈61% projected selection odds for cap-subject employers. Source: US Department of Labor LCA disclosure data (Oct 2025 – Jun 2026).

US H-1B: cap-subject employers enter a lottery weighted by wage level — Level I gets 1 entry, Level IV gets 4 (DHS projected selection odds ≈15% at Level I to ≈61% at Level IV). Universities and non-profit research employers are cap-exempt. The $100,000 fee for new petitions from abroad is currently blocked by a court order (appeal pending).

A verdict summarises public evidence. It is not legal advice and never a guarantee: the employer and the immigration authority decide. Sign in to factor in where you can already work.

About the role

The role You will help the Firefox DOM Core team improve the health of the Session History area. You will write tests to improve the coverage; you will fix tests and/or problems to improve the Gecko correctness. Responsibilities • Write Web-Platform tests to improve the coverage, and Gecko mochitests as needed • Fix the problems and pass the tests to improve the Gecko correctness • Work through code review with the relevant Gecko module owners and iterate to landing Definition of done Improved Session History test coverage and code correctness in Gecko, measured by passed test cases, allowing the team’s senior engineers to focus on security, performance and strategic projects. Required qualifications • Substantial experience in a browser-engine codebase or in automating for a browser-engine, ideally Firefox/Gecko. • Solid Javascript and applying that language skill to write automated tests. • Proficiency in and experience developing software in C++. • Strong debugging skills in a mature larget 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 web standards and Web Platform Tests. Find Jobs in Netherlands on Arbeitnow

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