Senior JavaScript Engineer

What you’ll do:

• Drive the design, development, and optimization of advanced JavaScript techniques to collect signals (user behavior, device characteristics, browser APIs) securely and efficiently.
• Own the full code lifecycle: architecture, development, deployment, monitoring, and continuous improvement.
• Guide the team’s technical direction, balancing innovation with stability and scalability.
• Lead, mentor, and grow a team of talented core JavaScript engineers focused on building detection sensors that operate across diverse browsers and devices.
• Collaborate closely with Product, Research, Security, and Engineering teams to align technical execution with broader product goals.

Who you are:

• 3+ years of hands-on software development experience, with deep expertise in vanilla JavaScript and browser internals.
• Strong understanding of web security concepts, browser APIs, and the nuances of cross-platform development.
• A JavaScript enthusiast who enjoys being hands-on: reviewing code, setting architecture and contributing to complex solutions.
• Excellent communication and collaboration skills, with the ability to work effectively across disciplines.
• Passionate about performance, security, and crafting elegant technical solutions.

Nice to have:

• Experience with typed backend languages (e.g., Go, Java).
• Familiarity with content delivery networks (CDNs) and large-scale deployment strategies.
• Background in cybersecurity, bot mitigation, or fraud prevention technologies.


Join us and lead the team that powers the intelligence behind HUMAN’s defense against online threats — helping to keep the internet human.