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# Senior · Staff · Principal Frontend Engineer

- **Company:** Lead Allies Inc
- **Location:** San Francisco, CA, United States
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** HTML, JavaScript (Programming Language), Browser Compatibility, Cascading Style Sheets (CSS), Databases, Software Debugging, Web Development, Design of User Interfaces, Human-Computer Interaction, Web Browsers, Responsive Web Design, Web Applications, Website Wireframe, ReactJS, Git, Vue.js, AngularJS, Front End Software Development, Software Version Control
- **Published:** November 6, 2026
- **Apply:** https://www.careerbuilder.com/job-details/senior-staff-principal-frontend-engineer-san-francisco-ca--1ddbc097-f58c-4cd6-aba8-d6f0683a2afe

## About the Role

User Interface/Experience (UI/UX), Internet Application, CSS (Cascading Style Sheet), JavaScript, User Interface/Experience (UI/UX), HTML (HyperText Markup Language), Technical/Engineering Design, Mock Up, Wireframes, Website Management, * HTML, CSS, and JavaScript: Proficiency in these foundational web development languages is essential.

 * Front-end frameworks and libraries: Knowledge of frameworks like React, Angular, or Vue.js is often required.

 * Responsive design: Ability to create websites and applications that adapt to different screen sizes and devices.

 * Version control systems (Git): Familiarity with version control systems like Git is crucial for collaborative development.

 * Accessibility: Understanding of accessibility principles and how to make websites usable for people with disabilities.

 * Problem-solving and debugging skills: Ability to identify and resolve issues in the code.

 * Testing and debugging: Ability to test and debug code to ensure it functions correctly.

## Description

A Front-End Developer is responsible for building the user-facing parts of websites and web applications, ensuring a seamless and visually appealing user experience. They translate designs into functional code using HTML, CSS, and JavaScript, and may also utilize frameworks and libraries., * Develop and implement user interfaces:
Front-end developers create the visual elements of websites and applications that users see and interact with.

 * Translate designs into code:
They take design mockups and wireframes and translate them into functional code using HTML, CSS, and JavaScript.

 * Build interactive elements:
They create interactive features and animations to enhance the user experience.

 * Ensure cross-browser compatibility:
They make sure the website or application functions correctly across different web browsers and devices., They optimize code for speed and efficiency, ensuring a fast and smooth user experience.

 * Collaborate with back-end developers:
They work closely with back-end developers to integrate the front-end with server-side logic and databases.

 * Maintain and update existing websites and applications:
They may be responsible for fixing bugs, implementing new features, and maintaining existing code.

 * Follow industry best practices:
They stay up-to-date on the latest front-end technologies and best practices.

 * Test and debug code:
They thoroughly test their code to ensure it functions as expected and debug any issues that arise.