Senior Software Engineer (JavaScript, MongoDB)

Job Title: Senior Software Engineer (JavaScript, MongoDB)
Location: Fremont, CA (onsite)
Position: Contract Direct W2 (No 3 rd Party Subcontractors Permitted)

Duration: 2+ Months Project Based with Potential Extension

September thru October 2026 with possible extension based on project needs

Overview
Our client is seeking an experienced Senior Software Engineer in Fremont, CA for an onsite contract opportunity. Candidates must be authorization to work in the U.S. without need for current or future visa sponsorship

The Senior Software Engineer will develop, enhance, and support complex software applications. This role requires a highly experienced full-stack engineer who can think critically through abstract technical problems, independently own solutions, and lead projects from definition through completion.

The ideal candidate brings deep expertise in JavaScript, TypeScript, MongoDB, ElectronJS, React, Node.js, REST APIs, and modern frontend development, along with strong software engineering, code review, and project leadership experience.
What You'll Do

• Analyze, develop, and modify complex software applications and information systems.
• Lead software projects by defining requirements, specifications, milestones, and tasks.
• Own technical solutions from initial problem definition through successful completion.
• Design and develop frontend and backend application functionality.
• Build and maintain RESTful APIs and server-side applications.
• Develop and manage SQL and NoSQL databases.
• Investigate application and system issues, isolate root causes, and implement resolutions.
• Improve application performance by identifying technical trends, developing specifications, and recommending solutions.
• Support business leadership in evaluating software and hardware requirements, options, risks, costs, and business impact.
• Track project activity, resolve issues, publish progress updates, and recommend corrective actions when needed.
• Perform code reviews and provide constructive technical feedback.
• Manage source-control activities including branching, merges, and conflict resolution.
• Mentor colleagues on software engineering standards and best practices.
• Work collaboratively across technical and business teams.

What You Bring to the Role (Required Experience)

• 10+ years of JavaScript experience.
• 7+ years of MongoDB experience.
• Experience with ElectronJS.
• Demonstrated ability to solve complex and abstract technical problems.
• Experience breaking projects into milestones and tasks and leading them through completion.
• Strong understanding of the software development lifecycle (SDLC).
• Experience with code reviews, branch management, merge conflict resolution.
• Software development best practices.
• Strong communication and organizational skills.

Frontend Technologies

• HTML
• CSS
• JavaScript
• TypeScript
• React.js or similar frontend libraries.
• CSS frameworks such as Tailwind CSS.
• UI frameworks such as Ant Design and shadcn.
• Global state-management tools such as Redux and React Context API.

Backend Technologies

• Node.js or comparable server-side technologies
• RESTful API development
• Server-side frameworks such as Express.js
• SQL and NoSQL database development and administration
• SQLite
• MySQL
• MongoDB

Education

• Degree in Information Technology or related field.

Compensation and Employment
This role requires authorization to work in the U.S. without current or future visa sponsorship. The expected hourly rate for this position is $70 - $99 per hour W2, depending on experience and qualifications. This role also qualifies for comprehensive benefits such as health insurance. TalentFish is committed to pay transparency and equal opportunity. The salary range provided is in compliance with applicable state and federal regulations. All offers are contingent upon the completion of a background check, which may include but is not limited to reference checks, education verification, employment verification, drug testing, criminal records checks, and any required certifications or compliance requirements based on the end client's background check policies and applicable laws.
TalentFish is an employee-owned company pioneering a new realm in talent acquisition. We are redefining IT staffing by evolving AI, video screening, and our unique platform. TalentFish focuses on providing the best employee, consultant, and client experience possible. TalentFish is an Equal Opportunity Employer; we embrace and encourage diversity.