Staff Engineer - Distributed Systems

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
 
Role Summary:
We’re hiring a Senior Full Stack Engineer to design, build, and scale the backend systems and frontend interfaces that power the Threads & Composer experience inside HighLevel Conversations. You’ll spend most of your time on backend and API design, data flows, and performance — while still owning the Vue 3 UI layer end-to-end. Your work will touch critical paths that process billions of messages per month, demanding reliability, throughput, and correctness at scale.
 
Team & System Overview:
The Conversations organization powers multi-channel communication across SMS, Email, WhatsApp, and DMs — handling over 2B messages each month. The Threads & Composer team owns the inbox and composer surfaces, and the backend services that deliver and store those interactions.You’ll work across Node.js microservices, GCP-based infra (GKE, Pub/Sub, Cloud Tasks), and MongoDB/Firestore storage layers, ensuring every message and UI state stays consistent, fast, and recoverable.

Responsibilities:: Own the architecture health of a billion-scale distributed system , its failure modes, capacity limits, consistency guarantees, and the interactions between 50+ deployments that no single team can see Approve critical-path designs. Changes that touch the system's core go through you, not as bureaucracy, but as the person accountable for the whole staying sound. When there's a disagreement, you make your case on merit Hunt gaps proactively , single points of failure, unbounded queues, missing idempotency, thundering herds, quiet data-loss windows, and drive the fixes before they become incidents Build the parts nobody else can. No sprint tickets. You prototype the risky architectural bets yourself, ship the remediation after serious incidents, and pair into the gnarliest cross-team bugs, roughly a quarter to a third of your time in code, all of it on the hardest problems Make resilience a property of the system, not a heroic act , degradation strategies, backpressure, isolation boundaries, capacity models that survive 10%+ month-over-month growth Raise the teams around you. Design reviews that teach, post-mortems that change architecture (not just add alerts), and patterns that 80+ engineers build on Set the standard for how AI-assisted engineering works safely on systems this critical, where a bad merge doesn't cost