Staff Software Engineer, Backend MSSP

horizon3ai; United States; Hybrid; USD 180,000 - 280,000; Full time

Benefits offered by this job

Stock options

Health, vision, and dental coverage

Flexible vacation

Parental leave

Job summary

horizon3ai seeks a seasoned Senior Backend Architect to provide technical leadership for backend services enabling partners to manage work across multiple customer environments. You will shape multi-tenant architecture, oversee production outcomes, and mentor teams across product and engineering.

The role combines strategic direction with hands-on engineering, focusing on secure data boundaries, scalable APIs, and reliable operations.

Qualifications

• Eight+ years of professional software engineering experience with backend/API focus.
• Track record of setting technical direction or leading architecture for production multi-tenant or distributed systems.
• Strong data modeling, reliability, and security boundary expertise in customer-facing systems.

Responsibilities

• Set technical direction for partner platform services, including account hierarchies and tenant isolation.
• Lead architecture for managing customer and sub-customer accounts and partner relationships.
• Establish patterns for secure data boundaries, API design, observability, and reliability.
• Stay hands-on with complex technical work and resolve ambiguous requirements.
• Align platform capabilities with partner needs across product, customer-facing, and engineering teams.
• Mentor engineers through design reviews, pairing, and documentation; own production issues.

Skills

Technical leadership

Backend architecture

Multi-tenant systems

API design

Security boundaries

Cloud services

Mentorship

Education

Bachelor's degree in CS/Engineering or equivalent

Job description

Role overview

Provide hands-on technical leadership for backend services that let service partners manage work across multiple customer environments. The role shapes multi-tenant architecture and partner workflows, while remaining accountable for implementation quality, security boundaries, reliability, and production results. It combines complex engineering work with cross-team alignment and mentorship.

Responsibilities

• Set technical direction for partner platform services, including account hierarchies, tenant isolation, delegated administration, and partner workflows.
• Lead architecture and implementation for managing customer and sub-customer accounts, allocating or retiring assets, and administering partner relationships.
• Establish patterns for secure data boundaries, API design, observability, reliability, and operational readiness.
• Stay hands-on with complex technical work and help teams resolve ambiguous requirements and tradeoffs.
• Work with product, customer-facing, and engineering teams to align platform capabilities with partner needs.
• Mentor engineers through design and code reviews, pairing, and technical documentation; take ownership of complex production issues and follow through on improvements.

Requirements

• At least eight years of professional software engineering experience, including deep backend and API experience.
• A track record of setting technical direction or leading architecture for production multi-tenant, platform, or distributed systems.
• Strong understanding of data modeling, service reliability, and security boundaries in customer-facing systems.
• Experience building and operating cloud-hosted services and owning production outcomes.
• Ability to influence across teams, mentor engineers, and explain technical tradeoffs clearly.
• A computer science, computer engineering, or related degree, or equivalent practical experience; backend experience in a modern language such as Python, Go, Java, or TypeScript.

Benefits and work setup

The listing describes remote and hybrid arrangements depending on role and location.

Full-time roles include stock options, health, vision, and dental coverage, flexible vacation, and parental leave.