Senior FullStack Engineer - Contacts

About HighLevel:HighLevel is an AI-powered business operating system that gives agencies, entrepreneurs and SMBs the infrastructure to build, automate and scale. Today, HighLevel supports SMBs across 150+ countries, fueling community-driven growth rooted in real customer outcomes. To date, businesses operating on HighLevel have generated over $7 billion in ecosystem value, demonstrating the impact of shared infrastructure at scale. By centralizing conversations, automation and intelligence into one system, we help businesses move faster, reduce complexity and execute efficiently. Behind the platform, HighLevel powers more than 4 billion API hits and 2.5 billion message events daily. With 250 terabytes of distributed data, 250+ microservices and over 1 million domain names supported, our architecture is built for performance, resilience and long-term scalability. Our people With over 2,000 team members across 10+ countries, HighLevel operates as a global, remote-first organization built for speed and ownership. We value initiative, clarity and execution, creating space for ambitious people to build systems that support millions of businesses worldwide. Here, innovation thrives, ideas are celebrated and people come first, no matter where they call home. Our impact Every month, HighLevel enables more than 1.5 billion messages, 200 million leads and 20 million conversations for the more than 1 million businesses we support. Behind those numbers are real people building independence, expanding opportunity and creating measurable impact. We’re proud to be a part of that. Learn more about us on our YouTube Channel or Blog Posts     About the Role: The Contacts Team is at the heart of our CRM platform, managing the core infrastructure for contact records, views, filters, segmentation, and more. Every product surface (for example, automation, campaigns, pipelines, or reporting) interacts with Contacts. We're building scalable, reliable, and flexible systems that power millions of interactions daily.   In this role, you will drive technical outcomes as a hands-on Individual Contributor. You will own high-impact initiatives across the Contacts domain. Responsibilities:

Architect & Scale: Design and build highly scalable and reliable backend services using Node.js, MongoDB, and ElasticSearch, ensuring optimal indexing, sharding, and query performance

Frontend Development: Develop and optimize user interfaces using Vue.js (or React/Angular) for an exceptional customer experience

Event-Driven Systems: Design and implement real-time data processing pipelines using Kafka, RabbitMQ, or ActiveMQ

Optimize Performance: Work on autoscaling, database sharding, and indexing strategies to handle millions of transactions efficiently

Cross-Functional Collaboration: Work closely with Product Managers, Data Engineers, and DevOps teams to align on vision, execution, and business goals

Quality & Security: Implement secure, maintainable, and scalable codebases while adhering to industry best practices

Code Reviews & Standards: Drive high engineering standards, perform code reviews, and enforce best practices across the development team

Ownership & Delivery: Manage timelines, oversee deployments, and ensure smooth product releases with minimal downtime

Mentor: Guide a team of developers, ensuring best practices in software development, clean architecture, and performance optimization

Requirements:

4+ years of hands-on software development experience

Strong proficiency in Node.js, Vue.js (or React/Angular), MongoDB, and Elasticsearch

Experience in real-time data processing, message queues (Kafka, RabbitMQ, or ActiveMQ), and event-driven architectures

Scalability expertise: Proven track record of scaling services to 200k+ MAUs and handling high-throughput systems

Strong understanding of database sharding, indexing, and performance optimization

Experience with distributed systems, microservices, and cloud infrastructures (AWS, GCP, or Azure)

Proficiency in CI/CD pipelines, Git version control, and automated testing

Strong problem-solving, analytical, and debugging skills

Excellent communication and leadership abilities—able to guide engineers while collaborating with stakeholders

Tech Stack:

Backend: Node.js, Nest JS, REST APIs, Redis, Firestore, Mongo, Elastic search

Frontend: Vue 2 + Vue 3 (Composition API), Pinia, TypeScript, Vite

Infrastructure: Docker, Kubernetes, GCP

Accessibility & Internationalization (i18n) best practices