Backend Engineer II

Cascade AI helps HR organizations transform how they operate with AI agents that automate critical HR functions, including support, open enrollment, onboarding, leave of absence, compensation, and more.

Our agents do far more than provide answers. They execute processes and workflows, streamline HR operations, and deliver employees the help they need instantly and conversationally. By combining Large Language Models (LLMs) with an organization's existing HR technology stack, Cascade agents streamline operations, improve employee experience, and unlock significant cost savings.

Cascade is deployed globally, with users on every continent, and supports multi-lingual work forces. We are proudly backed by Gradient Ventures, Google's AI fund, and trusted by Fortune 100 companies and leading enterprises, many of whom sign multi-year contracts. Founded by two former Microsoft engineers through the MIT Sandbox Innovation program, Cascade is now one of the fastest-growing AI companies in HR technology.

We have an exceptional advising team, including industry leaders such as the former VP of People Ops at Google and former CHRO of Airbnb.

If you like to work at the intersection of AI and cloud, collaborate across the organization, and thrive in a fast-paced startup environment, this role could be a great fit. Everyone joining at this stage will wear multiple hats and work across the product surface.

As a Backend Engineer II at Cascade, you will build and own core backend systems that power AI agents automating real HR work s is a hands-on role where you’ll ship production code weekly, take ownership of meaningful systems, and help define how AI agents execute complex workflows inside large enterprises.

You’ll work across APIs, data models, integrations, and LLM orchestration, turning ambiguous product needs into reliable, scalable backend systems. You’ll collaborate closely with product, frontend, and customer-facing teams, and you’ll be trusted to make good engineering decisions without heavy process or layers.

This role is ideal for engineers who enjoy moving fast without cutting corners, taking ownership, and building systems that are used daily by tens of thousands of people.

Level and Reporting

• This is a mid-level backend engineering role.
• This role reports directly to Cascade’s Chief Technical Officer (CTO).

This is a hybrid role based in Bellevue, WA. We expect team members to work from our Bellevue office four days per week to foster collaboration, accelerate learning, and build strong team cohesion. In-person time is critical for early-stage engineers to grow quickly, get real-time feedback, and stay aligned with the team.

• Salary range: $130k –$150k base, depending on experience.
• Equity: meaningful stock options so you share in Cascade’s upside.
• Competitive health coverage.
• 401(k).
• Unlimited PTO, with an emphasis on taking time off to recharge.

Work Authorization

• We are not able to sponsor visas for this role at this time.
• Candidates must be eligible to work in the United States.

You don’t need to have used all of these, but you should be excited to work in an environment that looks like this:

• Backend frameworks: Python with Flask and FastAPI.
• AI & orchestration: Lang Chain and modern LLM providers.
• Plus integrations with HRIS, ticketing, and communication tools.

What You’ll Do

• Build, own, and evolve backend services that power Cascade’s AI agent platform.
• Design and implement APIs that support conversational interactions, task execution, and long-running workflows.
• Develop and iterate on LLM orchestration logic in Python, including prompt execution, tool calling, state management, and evaluation.
• Integrate deeply with enterprise systems such as HRIS platforms (Workday, ADP, UKG), ticketing tools (Service Now, Jira), and communication tools (Slack, Microsoft Teams).
• Design data models and storage layers across relational and No
  
  SQL databases (Postgre
  
  SQL, Firestore).
• Build ingestion and retrieval pipelines for HR documents and structured data used by AI agents.
• Implement authentication, authorization, and access controls to meet enterprise security and compliance requirements.
• Own production reliability for your systems,…