AI Software Engineer — Build Scalable AI Platform & Agents

Stealth AI Research Lab; Cambridge (MA); On-site; USD 120,000 - 180,000; Full time

Job summary

Stealth AI Research Lab is seeking an AI software engineer to scale Cortex SDK/API and related products. You will collaborate with researchers and engineers, owning meaningful features from early weeks and contributing to production-grade software.

You’ll work on the Cortex SDK, API, and frontend, focusing on agent loops, tool calls, retrieval-based reasoning, and scalable cloud services. The role combines research and software engineering in a fast-moving startup environment.

Qualifications

• Degree in computer science or related field, or equivalent practical experience.
• 1–4 years of professional experience is ideal; exceptional newer grads are welcome.
• Strong software engineering fundamentals: clear, tested code, Git, code review, and issue tracking.
• Mastery of Python and/or TypeScript, experience building backend services and APIs.
• Familiarity with building LLM applications: retrieval-based systems, embeddings, and tool-using agents.

Responsibilities

• Build the core Cortex SDK, API, and products; work with researchers to implement algorithms.
• Improve the agent loop, planning, tool calls, and token-efficient performance.
• Backend development: design and ship services, data models and APIs on cloud infra (GCP).
• Polish the Cortex Studio frontend and other products for speed, reliability and delight.
• Raise the engineering bar: CI/CD, staging, test gates, safe rollouts, and monitored rollouts.

Skills

Python

TypeScript

Backend development

LLM applications

Retrieval systems

Git

Code review

Education

Bachelor's degree in Computer Science

Tools

Git

Jira

GCP

CI/CD

Job description

Stealth AI Research Lab is seeking an AI software engineer to scale Cortex SDK/API and related products. You will collaborate with researchers and engineers, owning meaningful features from early weeks and contributing to production-grade software.

You’ll work on the Cortex SDK, API, and frontend, focusing on agent loops, tool calls, retrieval-based reasoning, and scalable cloud services. The role combines research and software engineering in a fast-moving startup environment.