About Job: This is a cutting-edge marketing automation platform that helps businesses deliver personalized campaigns to their website visitors. Our JavaScript widget engine is the core technology that enables real-time campaign delivery and audience targeting across any website.
The Role: We are seeking a Senior JavaScript Engineer to lead the development of our widget engine. This role is critical to our product's success as the widget engine is the primary interface between our platform and our clients' websites.
What You'll Do:
1. Core Engine Development (40%) - Architect and develop the core widget engine using TypeScript - Implement campaign rendering and positioning system - Design and maintain the widget lifecycle management - Develop cross-browser compatible solutions - Optimize widget loading and execution performance - Implement proper cleanup and memory management
2. Audience Targeting System (30%) - Develop sophisticated audience targeting conditions: * Time-based triggers (delayed display, session timing) * Scroll depth detection and tracking * Browser and OS detection * Custom data field integration * Exit intent detection * User inactivity monitoring - Implement real-time condition evaluation - Design and maintain event handling system - Ensure reliable campaign triggering
3. API and Integration (20%) - Design and implement public APIs for external developers - Create utility functions for custom data management - Develop documentation and type definitions - Maintain backward compatibility - Implement security measures and data validation
4. Quality Assurance (10%) - Write comprehensive unit and integration tests - Implement error tracking and logging - Perform cross-browser testing - Monitor and optimize performance - Handle bug fixes and maintenance
Technical Requirements:
Must Have: - 5+ years of professional JavaScript/TypeScript development - Strong understanding of browser APIs and limitations - Experience with modern build tools (Rollup, Webpack) - Proficient in DOM manipulation and event handling - Experience with performance optimization - Strong debugging and problem-solving skills - Experience with version control (Git) - Understanding of cross-browser compatibility issues
Nice to Have: - Experience with marketing automation tools - Knowledge of A/B testing implementation - Understanding of web analytics - Experience with real-time data processing - Familiarity with privacy regulations (GDPR, CCPA)
Project Challenges You'll Solve: 1. Ensuring reliable campaign delivery across different websites and frameworks 2. Managing multiple concurrent audience conditions without performance impact 3. Implementing secure data handling and privacy compliance 4. Optimizing widget loading and execution in various environments 5. Handling edge cases in different browser environments
Development Environment: - Git for version control - TypeScript for type safety - Rollup for module bundling - Jest for testing - ESLint for code quality - Browser developer tools for debugging - CI/CD pipeline integration
What We Offer: - Competitive salary - Remote work flexibility - Opportunity to work on cutting-edge technology - Collaborative team environment - Professional development opportunities - Impact on product direction
Success Metrics: 1. Widget load time under 100ms 2. Zero memory leaks 3. 99.9% campaign delivery reliability 4. Successful integration with 100+ client websites 5. Positive developer feedback on API usability
Application Process: 1. Technical assessment 2. Code review discussion 3. Technical interview 4. Team fit interview 5. Offer
To Apply: Please submit your resume, GitHub profile, and a brief description of your most challenging JavaScript project. Include specific examples of how you've handled cross-browser compatibility issues and performance optimization.
Equal Opportunity Employer: We are committed to creating a diverse environment and are proud to be an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, or veteran status.
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