Upwork is seeking a contract Senior/Lead JavaScript Developer to design and build highly performant, robust systems that create outstanding user experiences for millions of independent professionals and clients. As part of our Hybrid Workforce Solutions team, you will collaborate with stakeholders to deliver high-quality solutions and contribute to the enhancement of our codebase.

What You'll Do

Collaborate with project stakeholders to understand requirements and deliver high-quality solutions.
Design, develop, test, and maintain scalable and robust server-side logic, databases, and APIs according to project requirements.
Develop, test, and maintain high-quality front-end code for web applications using languages like TypeScript or JavaScript and modern frameworks like Vue.js, Nuxt, React.js, or Angular.
Optimize front-end performance and ensure cross-browser compatibility.
Integrate front-end interfaces with backend APIs for seamless data flow.
Contribute to the enhancement of our codebase by improving quality and documentation and reducing technical debt.
Participate in code reviews and design reviews.
Document code and technical specifications for future reference.
Analyze system performance, respond to incidents within specified deadlines, and provide services during on-call rotations.
Provide services in the Scrum process, including sprint planning, daily stand-ups, and retrospective meetings.
Participate in project-critical meetings and provide regular status updates on deliverables.
Manage your time independently and effectively to achieve project deliverables, which may require an estimated 40 hours of project-related effort per week.
Coordinate with the team during core hours (8:00 am to 11:00 pm Pacific Time) to enhance project collaboration.

What We're Looking For

8+ years of professional software development experience.
Deep knowledge of modern JavaScript (ES6+) or TypeScript, CSS, and HTML.
Extensive experience with a modern JS framework, such as Vue (preferred), React, or Angular.
Experience with unit testing and end-to-end UI testing.
Basic understanding of accessibility (WCAG) guidelines and engineering principles.
Self-motivation, self-organization, and self-education skills.
English on at least an intermediate level (should be able to pass the technical interview in English).
Basic knowledge of PHP, server-side JavaScript or TypeScript, or other server-side languages. Basic knowledge of the Node.js backend framework.
Basic understanding of system design principles.
Extensive knowledge of REST.
Experience in writing well-structured, easily maintainable unit tests (such as JUnit, Mockito, etc).
Experience with relational databases.
Consistent track record of collaborating with large, distributed teams of engineers over documentation and code.
A desire to learn new technologies and continually develop your professional skills.
Comfortable working with AWS.
Experience building / supporting high-load web applications and solving scalability issues.

Nice to Have

Flutter experience or mobile experience is a major plus.

Technical Stack

Languages: TypeScript, JavaScript, CSS, HTML, PHP
Frameworks & Libraries: Vue.js, Nuxt, React.js, Angular, Node.js
APIs & Services: REST, AWS
Testing & Tools: JUnit, Mockito
Data: Relational Databases

Team & Environment

You will be part of Upwork’s Hybrid Workforce Solutions (HWS) Team, a global group of professionals that support Upwork’s business.

Work Mode

This is a fully remote position open to candidates in Europe. Some roles or urgent matters may require availability until 12:00 pm Pacific Time on occasion.

Upwork is proudly committed to fostering a diverse and inclusive workforce and never discriminates based on race, religion, color, national origin, gender (including pregnancy, childbirth, or related medical condition), sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, or other applicable legally protected characteristics.