Senior Back End Engineer - AI Workflow/Application Builder

Senior Backend Engineer - AI Application Builder

SoMa, San Francisco, CA Full-Time Onsite

Salary: $200K-$325K + Meaningful Equity (1%+)

Join an early-stage AI SaaS start-up creating an application builder that empowers business users to build custom applications where humans and AI collaborate seamlessly across enterprise systems. The company addresses complex enterprise challenges, including multi-day workflows, cross-system integrations (ERP/CRM/financial platforms), secure VPC hosting, and enterprise-grade observability, logging, identity, and compliance controls.

About the Role

We're looking for a Backend Engineer to lead the development of backend systems and architecture. This is a rare opportunity to take ownership of core systems in an early-stage company, shaping architecture, scalability, and reliability from the ground up.

You'll tackle challenging problems like orchestrating multi-system workflows, processing large-scale data asynchronously, and safely executing AI-generated code - all while collaborating closely with the applied AI team.

What You'll Do

Design and build the core workflow engine - the orchestration layer connecting agents, data sources, and frontend views.

Develop and scale the TypeScript-based backend, handling asynchronous execution, retries, and deterministic routines.

Build and maintain integration layers for REST APIs, SQL sources, and third-party systems.

Collaborate with the applied AI engineering team to integrate automation and intelligence across systems.

Define and enforce best practices for backend architecture, reliability, and developer experience as the company scales.

Who You Are (Must-Haves)

4-15 years of professional software engineering experience.

Strong experience with TypeScript, Node.js, and modern backend architectures.

Experience designing complex data models and managing asynchronous tasks/workflows.

Prior experience working in early-stage startups or high-growth environments.

Experience integrating multiple systems, including REST APIs and SQL sources.

Excited by building scalable systems and comfortable in a startup environment.

Excellent problem-solving, collaboration, and communication skills.

Nice-to-Haves

Experience building or integrating AI / LLM-powered applications.

Familiarity with Temporal or similar orchestration/workflow systems.

Exposure to other modern backend frameworks or cloud technologies (AWS, GCP, Kubernetes).

Why Join?

Competitive salary: $200K-$325K + meaningful equity (1%+) in an early-stage company.

Work alongside experienced founders who have successfully scaled AI and enterprise SaaS products.

Shape the architecture and direction of a high-impact backend system used across complex workflows.

Be part of a small, highly motivated team at the forefront of AI and enterprise applications.