AI Agents Engineer – Python, FastAPI, RAG & Tool Calling (On-site Bay Area)

MaxIT Consulting - Max Corporate Group; Los Altos (CA); On-site; USD 180,000 - 260,000; Full time

Job summary

MaxIT Consulting - Max Corporate Group in Los Altos, CA is seeking a Backend Engineer, Applied Agents to join a venture-backed, early-stage AI company building an AI-native operating system for drug development programs. You will design, build and operate the agent layer and backend systems powering multi-step tasks inside real workflows.

The role emphasizes building runtime and tooling, ensuring reliability, creating APIs with Python, FastAPI and Postgres, and grounding AI outputs with

Qualifications

• 2+ years shipping and operating production backend systems end to end.
• Strong fundamentals in API design, data modeling, databases and system reliability.
• Hands-on production experience with LLM systems: RAG, vector databases and agents.
• Has built, or deeply traced, an agent runtime or harness: tool calling, sandboxing, memory.
• Ships fast on incomplete specs and uses AI coding tools daily.

Responsibilities

• Build the agent runtime and harness, tool-calling infrastructure, sandboxed code execution and agent memory.
• Own reliability and observability of multi-step agent tasks.
• Design and build backend services and APIs on Python, FastAPI and Postgres.
• Design and operate vector databases, semantic search and RAG systems, tuning quality and latency.
• Build large-scale ingestion, cleaning and indexing pipelines for scientific and regulatory documents.
• Ground AI outputs in source data with traceable, verifiable citations.
• Work directly with founders, domain experts and early customers, owning outcomes.

Skills

API design

Data modeling

Databases

System reliability

LLM systems

Vector databases

Agent runtime

Tool calling

Sandboxing

Memory

AI coding tools

Tools

Claude Code

Cursor

Job description

Los Altos, CA (San Francisco Bay Area) | On-site | Full-time

MaxIT Consulting is looking for a Backend Engineer, Applied Agents to join a venture-backed, early-stage AI company building an AI-native operating system for drug development programs, already used by leading biopharma companies.

The Opportunity

You will design, build and operate the agent layer and the backend systems that power it: agents that carry out multi-step tasks inside real workflows, call tools reliably, run code in sandboxed environments, keep context and deliver verifiable results.

Key Responsibilities

• Build the agent runtime and harness, tool-calling infrastructure, sandboxed code execution and agent memory.


• Own reliability and observability of multi-step agent tasks.


• Design and build backend services and APIs on Python, FastAPI and Postgres.


• Design and operate vector databases, semantic search and RAG systems, tuning quality and latency.


• Build large-scale ingestion, cleaning and indexing pipelines for scientific and regulatory documents.


• Ground AI outputs in source data with traceable, verifiable citations.


• Work directly with founders, domain experts and early customers, owning outcomes.

Required Qualifications

• 2+ years shipping and operating production backend systems end to end.


• Strong fundamentals in API design, data modeling, databases and system reliability.


• Hands-on production experience with LLM systems: RAG, vector databases and agents.


• Has built, or deeply traced, an agent runtime or harness: tool calling, sandboxing, memory.


• Ships fast on incomplete specs and uses AI coding tools (Claude Code, Cursor) daily.

Nice to Have

• Built an in-house agentic harness or internal tools to boost a team's agentic development.


• LangGraph or agent frameworks in production; AWS, Terraform and Kubernetes.


• Enterprise SaaS, healthcare or life sciences products; seed or early-stage startup experience.

Work Arrangement

On-site role in Los Altos, CA (San Francisco Bay Area); fully remote is not possible. Candidates must live in or relocate to the Bay Area and must already be authorized to work in the United States.