Staff Backend Engineer - Users

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 2 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 micro-services, 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 2 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. Role Summary: As a Staff Engineer on the Users team, you will be the technical anchor for identity, access, auditing, notifications and security foundations across our multi-tenant SaaS platform. This role is not about feature velocity - it’s about building systems that are correct, resilient, and safe by default, and enabling other teams to move fast without breaking trust. You’ll work closely with EMs, Product, and other engineers to design and evolve core primitives such as users, roles, permissions, tokens, and tenant isolation, auditing, notifications - at scale. Responsibilities:

Design and evolve secure multi-tenant architectures (Agency → Account → App or equivalent hierarchy) for 100k+ agencies

Define and enforce tenant isolation guarantees at data, API, and infra levels

Build and review authorization models (RBAC / ABAC / hybrid)

Own token systems (API keys, OAuth flows, JWTs, scoped tokens, rotation, expiry)

Design fine-grained scopes for internal APIs, public APIs, and partner integrations

Map scopes → permissions → resources consistently

Prevent over-scoped tokens and privilege escalation

Lead security-critical backend designs (authZ boundaries, impersonation, auditability)

Set patterns for secure-by-default APIs used by internal and external teams

Partner with Infra/Security teams on Secrets management, Key rotation, Rate limiting & abuse prevention, Compliance readiness (SOC2 style thinking)

Act as a multiplier: raise the security bar across engineering via reviews, RFCs, and mentoring

Requirements:

8+ years of backend engineering experience

Proven experience building secure, multi-tenant SaaS platforms

Deep understanding of: Authorization models (RBAC, ABAC), OAuth2 / JWT / API key systems, Threat modeling & security tradeoffs

Strong system design skills - especially for long-lived platformsComfort owning ambiguous, high-impact areas

Nice to have:

Experience designing platforms used by multiple internal teams

Security reviews, incident learnings, or compliance exposure

Experience with large-scale migrations (auth or identity related)

Background in developer platforms or core infrastructure teams