Sr Fullstack Javascript Developer

Brief Description

As part of our interview process and our commitment to building high-performing teams, we’ve partnered with The Culture Index Program to better understand work styles and team dynamics. To support this process, we kindly ask you to complete a brief survey as part of the application process when submitting your profile. It should take no more than 7 minutes, and there are no right or wrong answers. We appreciate your participation and look forward to learning more about how you might fit within our team!

Culture Index Survey: https://go.cultureindex.com/p/weJLJlIGZ2DauZkoW

Collectivus Holdings guides many of the most prestigious brands in the Collecting, Trading Card Game, and Hobby industries. With a century's worth of collective experience in driving product and service innovation, high-end quality standards, and elevated customer experience, Collectivus brands are among the most recognized and loved throughout the world by the communities they serve.

Website: https://www.collectivusholdings.com

Locations: Aarhus – Dallas – Delhi – Lisbon – Nashville – Worldwide

Title: Senior Full-Stack JavaScript Developer (Node.js / NestJS / Next.js)

Job Location: Remote - US

We are seeking a Senior Full-Stack JavaScript Developer (Node.js / NestJS / Next.js) to take technical ownership of both backend and frontend architecture. This role focuses on building and maintaining scalable, secure, and high-performance web applications using Node.js, NestJS, and Next.js. You will work with a high degree of autonomy, collaborate closely with product, frontend, and infrastructure teams, and help set engineering standards while mentoring junior developers.

Key Responsibilities

• Design, develop, and maintain backend services using Node.js, NestJS, and TypeScript
• Build, document, and optimize RESTful APIs and integrate third-party services
• Develop and maintain frontend applications using Next.js
• Design and optimize PostgreSQL schemas, queries, and migrations
• Define and maintain API contracts between frontend and backend systems
• Ensure platform security, performance, scalability, and reliability
• Conduct code reviews, enforce best practices, and mentor junior developers
• Participate in system architecture decisions and technical design discussions
• Troubleshoot, debug, and resolve production issues
• Manage deployments and support applications on Linux/Ubuntu server
• Maintain technical documentation and source control using Git/bitbucket

Qualifications

• 5+ years of professional experience with Node.js
• Strong hands-on experience with NestJS and TypeScript
• Solid experience building frontend applications with Next.js
• Strong understanding of HTTP, authentication, sessions, and web security best practices
• Hands-on experience with PostgreSQL, including schema design and query optimization
• Proven experience building and maintaining production-grade APIs
• Comfortable working in Linux/Ubuntu environments
• Strong knowledge of Git workflows, debugging, and testing
• Ability to work independently and take end-to-end technical ownership
• Strong problem-solving skills and attention to detail

Nice to Have (Optional)

• Experience with containerization (Docker) and CI/CD pipelines
• Familiarity with cloud platforms (AWS, GCP, or Azure)
• Experience with background jobs, queues, or event-driven systems
• Exposure to monitoring, logging, and observability tools
• Prior experience mentoring or leading small engineering teams