Senior Software Engineer, Web Capture

Company: FullStory

Job Category: Software Engineering / JavaScript / TypeScript / Go

Contract Type: Full-Time, Permanent Location: Remote — USA

Salary: $145,000–$170,000 base + up to 10% discretionary bonus

Application Link: https://www.fullstory.com/careers/jobs/3b8d231f-ae95-4f95-84a1-8c2e918b0d4f

Job Description: You'll work on FullStory's Web Capture team, building and maintaining the JavaScript/TypeScript agent that captures behavioral data from millions of users' browser sessions at scale. This is deep, high-impact systems work — you'll be crafting code that runs in every browser on client websites and must be fast, lightweight, reliable, and privacy-respecting.

Key Responsibilities:

• Design and build FullStory's web capture agent in JavaScript/TypeScript, running in browsers across millions of sessions daily
• Develop Go backend services that process and ingest captured behavioral data at scale
• Ensure captured data is accurate, complete, and respects privacy constraints
• Optimize agent performance — minimizing payload size, CPU overhead, and memory footprint
• Collaborate with infrastructure and data platform teams on ingestion pipelines
• Build and maintain automated testing frameworks for browser-environment validation

Requirements:

• Strong JavaScript and TypeScript skills, ideally with browser-environment expertise
• Go (Golang) backend development experience
• Experience working on client-side instrumentation, SDKs, or agent-style libraries
• Understanding of browser APIs, security sandboxing, and cross-origin considerations
• Experience with data serialization, protocol design, and high-throughput ingestion systems