CrawlJobs Logo

Software Engineer, DOM Core

mozilla.org Logo

Mozilla

Location Icon

Location:

Category Icon

Job Type Icon

Contract Type:
Not provided

Salary Icon

Salary:

Not provided

Job Description:

Join the global DOM: Core team of engineers passionate about the Web. We are the team responsible for page navigation, document loading, event handling, user interaction, and text editing in Gecko, the engine behind Firefox. You will implement standardized APIs like DOM, HTML, Events, Editor, and Clipboard. You will push the boundaries of what the Web is capable of. Your responsibilities will include writing code, tests, as well as building prototypes, solving problems, while continuously learning and growing as an engineer.

Job Responsibility:

  • Improve the DOM, HTML, editing, user interaction capabilities of our Web engine, with a focus on performance, Web compatibility, and standards correctness
  • Read and implement API specifications, as well as contributing to the standards process by raising issues or participating in discussions
  • Develop and debug in a multi-language, multi-threaded and multi-process code base
  • Work primarily in C++ and write tests largely with HTML and JavaScript
  • Collaborate with a geographically distributed development team

Requirements:

  • Proficiency in and experience developing software in C++
  • Ability to learn a large and complex code base quickly
  • Comfortable contacting people and driving discussions
  • Motivated to learn new tools and techniques for improving existing software
  • Familiarity with one or more of the following, or ability to pick them up in a timely manner: Multi-process architecture
  • Debugging memory usage or performance profiling
  • The modern Web technologies (JavaScript, HTML, and/or CSS)
  • Commitment to our values: Welcoming differences
  • Being relationship-minded
  • Practicing responsible participation
  • Having grit
What we offer:
  • Generous performance-based bonus plans
  • Rich medical, dental, and vision coverage
  • Generous retirement contributions with 100% immediate vesting
  • Quarterly all-company wellness days
  • 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)
  • Flexible work environment
  • Industry-leading paid parental leave
  • Reimbursement for professional development (up to $3,000/year)
  • A work setup including the latest hardware and software of your choice

Additional Information:

Job Posted:
January 08, 2026

Employment Type:
Fulltime
Work Type:
Remote work
Job Link Share:

Looking for more opportunities? Search for other job offers that match your skills and interests.

Briefcase Icon

Similar Jobs for Software Engineer, DOM Core

Front-End Developer

Front-End Developer Job Description
Location
Location
Salary
Salary:
Not provided
ryzlabs.com Logo
Ryz Labs
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • A strong knowledge of modern React using TypeScript
  • Familiarity with modern Angular
  • A strong foundation in core web technologies (HTML, CSS, javascript with the DOM)
  • Ability to maintain and debug a large Single-Page Application
  • Ability to write unit tests as well as to structure code in a way that makes testing easier
  • Strong knowledge of version control systems (git)
  • Experience with Project management software (Jira, Linear, etc.) and the agile workflow
Job Responsibility
Job Responsibility
  • Collaborate with UI/UX designers, software engineers, data engineers, and data scientists to craft specialty web apps, APIs, and more
  • Work in several ecosystems, and there will always be an exciting new project or feature to develop
Read More
Arrow Right

Staff Software Engineer

Xometry is seeking a Staff Software Engineer to join our Buyer Experience techno...
Location
Location
United States , Waltham
Salary
Salary:
140000.00 - 230000.00 USD / Year
cherry.vc Logo
Cherry Ventures
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • At least 7 years of experience in software development, in a fast-paced, product-driven environment
  • Experience with a marketplace product is highly desired
  • Strong technical expertise in a full-stack environment
  • Familiar with: REST API design, The core of HTML, DOM, and CSS, Python
  • Expected to become proficient in Python, Rust, and React/Typescript design and development
  • Demonstrated ability to interact and communicate effectively with junior-level ICs all the way to technology, product, and business executives
  • Excellent leadership, execution, and communication skills
Job Responsibility
Job Responsibility
  • Hands-On Technical Leadership: writing and reviewing plans for new projects, and then participating in implementation with the team
  • Guide Innovation: Champion the adoption of a good mix of traditional and cutting-edge technologies and methods
  • Teaching & Mentorship: serve as a mentor and guide to engineers across the organization
  • Code Review: do code review and mentor others within the organization to perform good code reviews
  • Operational Excellence: Guarantee the delivery of superior software that not only meets but exceeds customer expectations
  • Collaborative Strategy: Forge strong partnerships with product managers, designers, and company leadership
What we offer
What we offer
  • 401(k) match
  • medical, dental and vision insurance
  • life and disability insurance
  • generous paid time off including vacation, sick leave, floating and fixed holidays, maternity and bonding leave
  • EAP, other wellbeing resources
  • Fulltime
Read More
Arrow Right

Staff Software Engineer

Xometry is seeking a Staff Software Engineer to join our Buyer Experience techno...
Location
Location
United States , North Bethesda
Salary
Salary:
140000.00 - 230000.00 USD / Year
cherry.vc Logo
Cherry Ventures
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • At least 7 years of experience in software development, in a fast-paced, product-driven environment
  • Experience with a marketplace product is highly desired
  • Strong technical expertise in a full-stack environment. You should be familiar with: REST API design, The core of HTML, DOM, and CSS. Python
  • You will be a part of full-stack teams and you are expected to become proficient in Python, Rust, and React/Typescript design and development
  • Demonstrated ability to interact and communicate effectively with junior-level ICs all the way to technology, product, and business executives
  • Excellent leadership, execution, and communication skills
Job Responsibility
Job Responsibility
  • Hands-On Technical Leadership: Your primary role is writing and reviewing plans for new projects, and then participating in implementation with the team
  • Guide Innovation: Champion the adoption of a good mix of traditional and cutting-edge technologies and methods. You have the experience to guide us out of “our way” of doing things when needed, and to double down on our existing tech and methods where appropriate
  • Teaching & Mentorship: You will serve as a mentor and guide to engineers across the organization, teaching and mentoring them to grow their skills
  • Code Review: You will do code review and mentor others within the organization to perform good code reviews
  • Operational Excellence: Guarantee the delivery of superior software that not only meets but exceeds customer expectations, while aligning with the strategic business timelines
  • Collaborative Strategy: Forge strong partnerships with product managers, designers, and company leadership to promote a culture of open communication, good collaboration, and high standards
What we offer
What we offer
  • 401(k) match
  • medical, dental and vision insurance
  • life and disability insurance
  • generous paid time off including vacation, sick leave, floating and fixed holidays, maternity and bonding leave
  • EAP, other wellbeing resources
  • Fulltime
Read More
Arrow Right

Staff Software Engineer

Xometry is seeking a Staff Software Engineer to join our Buyer Experience techno...
Location
Location
United States , Lexington
Salary
Salary:
Not provided
cherry.vc Logo
Cherry Ventures
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • At least 7 years of experience in software development, in a fast-paced, product-driven environment
  • Experience with a marketplace product is highly desired
  • Strong technical expertise in a full-stack environment. You should be familiar with: REST API design, The core of HTML, DOM, and CSS. Python
  • You will be a part of full-stack teams and you are expected to become proficient in Python, Rust, and React/Typescript design and development
  • Demonstrated ability to interact and communicate effectively with junior-level ICs all the way to technology, product, and business executives
  • Excellent leadership, execution, and communication skills
Job Responsibility
Job Responsibility
  • Hands-On Technical Leadership: Your primary role is writing and reviewing plans for new projects, and then participating in implementation with the team
  • Guide Innovation: Champion the adoption of a good mix of traditional and cutting-edge technologies and methods. You have the experience to guide us out of “our way” of doing things when needed, and to double down on our existing tech and methods where appropriate
  • Teaching & Mentorship: You will serve as a mentor and guide to engineers across the organization, teaching and mentoring them to grow their skills
  • Code Review: You will do code review and mentor others within the organization to perform good code reviews
  • Operational Excellence: Guarantee the delivery of superior software that not only meets but exceeds customer expectations, while aligning with the strategic business timelines
  • Collaborative Strategy: Forge strong partnerships with product managers, designers, and company leadership to promote a culture of open communication, good collaboration, and high standards
Read More
Arrow Right

Staff Software Engineer, Frontend

You'll lead critical frontend initiatives as Gamma scales to serve hundreds of m...
Location
Location
United States , San Francisco
Salary
Salary:
230000.00 - 310000.00 USD / Year
gamma.app Logo
Gamma
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • 8+ years of experience as a frontend software engineer with deep expertise in building production web applications
  • Strong understanding of modern JavaScript/TypeScript, ReactJS (with hooks), and asynchronous programming patterns
  • Deep knowledge of the browser DOM, React's virtual DOM, mutation observers, and event propagation
  • Experience with state management in React, preferably with Redux
  • Strong grasp of computer science fundamentals
  • Experience working in large, complex production-scale frontend codebases
Job Responsibility
Job Responsibility
  • Build and maintain the core foundations of our collaborative editor using CRDTs and WebSockets
  • Architect complex AI-powered features and workflows that integrate LLMs seamlessly into the user experience
  • Lead frontend performance optimization initiatives to ensure the app stays fast at scale
  • Design and implement sophisticated drag and drop interfaces for intuitive content manipulation
  • Contribute to and suggest improvements for open source projects at the core of our application
  • Create integrations with other platforms and build embedded applications
  • Mentor and guide other engineers
What we offer
What we offer
  • competitive equity
  • Fulltime
Read More
Arrow Right

Fullstack Engineer (FE Oriented) - Core Team

Coralogix is a modern, full-stack observability platform transforming how busine...
Location
Location
Salary
Salary:
Not provided
coralogix.com Logo
Coralogix
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • 4+ years of professional Software Development experience: Proven track record of building, deploying and maintaining production-grade applications
  • Expert-level Angular & State Management: 4+ years of deep hands-on experience with Angular (2+) and NgRx/Store. You should be comfortable architecting complex data flows and optimizing reactive patterns
  • Modern Web Ecosystem: Strong command of the 'Web Fundamentals' - including TypeScript, advanced CSS/SCSS (Flexbox, Grid) and a deep understanding of browser APIs, performance optimization and DOM manipulation
  • Full-Stack Awareness: Working experience with Node.js (preferred) to collaborate effectively on API design and understand the end-to-end lifecycle of a request
  • SaaS at Scale: Experience building and supporting large-scale SaaS production services, with an understanding of multi-tenancy, high availability and performance monitoring
Job Responsibility
Job Responsibility
  • End-to-end development and ownership of our products and features, from design, provide a performance, scalable to production
  • Solving diverse complex problems of high scale
  • Collaborate with other Engineers and Product s to improve our products
  • Fulltime
Read More
Arrow Right

Fullstack Engineer (FE Oriented) - Core Team

Coralogix is a modern, full-stack observability platform transforming how busine...
Location
Location
Poland
Salary
Salary:
Not provided
coralogix.com Logo
Coralogix
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • 4+ years of professional Software Development experience: Proven track record of building, deploying and maintaining production-grade applications
  • Expert-level Angular & State Management: 4+ years of deep hands-on experience with Angular (2+) and NgRx/Store. You should be comfortable architecting complex data flows and optimizing reactive patterns
  • Modern Web Ecosystem: Strong command of the "Web Fundamentals" - including TypeScript, advanced CSS/SCSS (Flexbox, Grid) and a deep understanding of browser APIs, performance optimization and DOM manipulation
  • Full-Stack Awareness: Working experience with Node.js (preferred) to collaborate effectively on API design and understand the end-to-end lifecycle of a request
  • SaaS at Scale: Experience building and supporting large-scale SaaS production services, with an understanding of multi-tenancy, high availability and performance monitoring
Job Responsibility
Job Responsibility
  • End-to-end development and ownership of our products and features, from design, provide a performance, scalable to production
  • Solving diverse complex problems of high scale
  • Collaborate with other Engineers and Product s to improve our products
  • Fulltime
Read More
Arrow Right

React Native Developer

We are looking for experienced React Native Developers to join our team. This ro...
Location
Location
India , Jaipur
Salary
Salary:
Not provided
Sarvika Technologies
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • Deep knowledge of React Native along with an extensive understanding of hooks, application life-cycle, and code architecture
  • Champion of the tools and readily used RN libraries (like React-Native-Fast-Image, React-Navigation, Redux, and Network libraries)
  • Good technical background hands-on experience in using React.js, Node
  • Solid understanding of object-oriented programming
  • Should have a crystal understanding of App architecture and how to React interacts with the native layers for iOS and Android respectively
  • Minimum 3 years’ experience in React Native development
  • Strong proficiency in JavaScript, including DOM manipulation and the JavaScript object model
  • Proficient in coding, debugging unit testing
  • Good understanding of design guidelines, SDK, and excellent JavaScript skills, Core AWS Services, and their core principles
  • Knowledge in Hooks, NPM or Yarn, GIT, and VS Code
Job Responsibility
Job Responsibility
  • Translating design and wireframes into high-quality code, with an eye for performance on specific target devices
  • Write unit test and perform functional verification for the responsible modules
  • Perform code reviews and sanity checks for the code developed
  • Developing new user-facing features using React.js and translating designs and wireframes into high-quality code
  • Participate fully in agile software development team and rituals
  • actively participate in all ceremonies, review user stories participate in planning sessions, estimate effort for stories/tasks, etc
  • Implementation of best practices, performance improvements and do code reviews
  • Building reusable components and libraries for future use
  • Should ace at writing modular and reusable code across the system
  • Enable other developers to use it in their projects extensively
Read More
Arrow Right