Cryptocurrencies 21,955
Market Cap $2.92T
BTC Dominance 58.72 %

Cryptocurrencies : 21,955

Total Market Cap : $2.92T

BTC Dominance : 58.72 %

LIVE
Mkt Cap $2.92T BTC Dom 58.72 % BTC BTC $85,569.00 ▼ -0.14% ETH ETH $2,697.74 ▼ -0.48% USDT USDT $0.999982 ▲ +0.00% BNB BNB $779.47 ▼ -0.95% XRP XRP $1.50 ▼ -0.07% USDC USDC $0.99996 ▼ 0.00% SOL SOL $120.92 ▲ +0.32% TRX TRX $0.335692 ▼ -0.24% FIGR_HELOC FIGR_HELOC $1.04 ▼ -0.22% ZEC ZEC $1,339.22 ▼ -0.36% HYPE HYPE $92.10 ▼ -2.75% DOGE DOGE $0.093512 ▼ -2.04% LINK LINK $13.98 ▲ +0.43% XMR XMR $555.26 ▼ -0.25% ADA ADA $0.270637 ▲ +0.71% WBT WBT $85.44 ▼ -0.29% USDS USDS $0.999823 ▼ -0.01% RAIN RAIN $0.011578 ▲ +1.45% LEO LEO $8.90 ▼ -0.50% XLM XLM $0.212561 ▼ -1.09% NEAR NEAR $5.17 ▼ -1.41% BCH BCH $314.37 ▼ -0.31% UNI UNI $8.60 ▼ -5.98% LTC LTC $69.04 ▼ -1.38% CC CC $0.12738 ▲ +0.63% Mkt Cap $2.92T BTC Dom 58.72 % BTC BTC $85,569.00 ▼ -0.14% ETH ETH $2,697.74 ▼ -0.48% USDT USDT $0.999982 ▲ +0.00% BNB BNB $779.47 ▼ -0.95% XRP XRP $1.50 ▼ -0.07% USDC USDC $0.99996 ▼ 0.00% SOL SOL $120.92 ▲ +0.32% TRX TRX $0.335692 ▼ -0.24% FIGR_HELOC FIGR_HELOC $1.04 ▼ -0.22% ZEC ZEC $1,339.22 ▼ -0.36% HYPE HYPE $92.10 ▼ -2.75% DOGE DOGE $0.093512 ▼ -2.04% LINK LINK $13.98 ▲ +0.43% XMR XMR $555.26 ▼ -0.25% ADA ADA $0.270637 ▲ +0.71% WBT WBT $85.44 ▼ -0.29% USDS USDS $0.999823 ▼ -0.01% RAIN RAIN $0.011578 ▲ +1.45% LEO LEO $8.90 ▼ -0.50% XLM XLM $0.212561 ▼ -1.09% NEAR NEAR $5.17 ▼ -1.41% BCH BCH $314.37 ▼ -0.31% UNI UNI $8.60 ▼ -5.98% LTC LTC $69.04 ▼ -1.38% CC CC $0.12738 ▲ +0.63%

Contract Software Engineer - DOM Core Firefox/Gecko

Mozilla
On-site United Kingdom Software Engineering

Posted Sep 24, 2026

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.
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