Software Development Engineer III - Core CRM

About HighLevel

HighLevel is an AI powered, all-in-one white-label sales & marketing platform that empowers agencies, entrepreneurs, and businesses to elevate their digital presence and drive growth. We are proud to support a global and growing community of over 1 million businesses, comprised of agencies, consultants, and businesses of all sizes and industries. HighLevel empowers users with all the tools needed to capture, nurture, and close new leads into repeat customers. As of mid 2025, HighLevel processes over 4 billion API hits and handles more than 2.5 billion message events every day. Our platform manages over 470 terabytes of data distributed across five databases, operates with a network of over 250 microservices, and supports over 1 million hostnames.

Our People With over 1,500 team members across 15+ countries, we operate in a global, remote-first environment. We are building more than software; we are building a global community rooted in creativity, collaboration, and impact. We take pride in cultivating a culture where innovation thrives, ideas are celebrated, and people come first, no matter where they call home.

Our Impact As of mid 2025, our platform powers over 1.5 billion messages, helps generate over 200 million leads, and facilitates over 20 million conversations for the more than 1 million businesses we serve each month. Behind those numbers are real people growing their companies, connecting with customers, and making their mark - and we get to help make that happen.

About the Role

We are building systems that operate at scale - high write volumes, real-time state sync, and burst traffic that doesn’t politely warn before it arrives. We are looking for engineers who love owning systems end-to-end, care deeply about performance and reliability, and want to build things that don’t just work - but last. This is not a ticket-execution role, its a system ownership role.

Responsibilities

Backend System Ownership

Design and evolve Node.js / NestJS services powering systems that operate at scale Take architectural decisions that balance scale, cost, and long-term maintainability

API Craftsmanship

Build well-typed, thoughtful REST contracts for high volume flows Think in versioning, backward compatibility, and clean boundaries

Data at Scale

Model and optimize MongoDB / Firestore schemas for high read/write workloads Design atomic updates and consistency strategies for distributed systems

Scalability & Resilience

Implement queues, caching layers, and rate limiting to handle burst traffic gracefully Design for failure modes before they happen

Frontend Integration

Ship modular Vue 3 UIs that efficiently consume APIs Optimize realtime updates and state management (Pinia) Improve Core Web Vitals and perceived performance

Observability & Production Ownership

Instrument logs, metrics, traces, and alerts Participate in on-call Debug real production issues Drive post-mortems to meaningful closure (not just documents)

Mentorship & Leverage

Review code thoughtfully Support junior engineers Raise engineering standards across the team

Requirements

4+ years of professional engineering experience Strong backend-heavy fullstack background Deep comfort with Node.js + TypeScript Experience building and scaling microservices (NestJS / Express) Modern frontend experience (Vue 3 or similar) Strong understanding of: API design, Data modeling, Distributed systems tradeoffs, Concurrency & rate limiting Real production debugging experience Comfortable in cloud-native environments (GCP / AWS) CI/CD and containerization familiarity

Nice to Have

Pub/Sub or message queue experience Event-driven systems exposure Domain-driven design familiarity Performance optimization work Experience reducing infra costs