Sixtyfour

People Intelligence at Scale

Senior Software Engineer - AI Engineering

$150K - $250K0.10% - 0.30%San Francisco, CA, US
Job type
Full-time
Role
Engineering, Full stack
Experience
Any (new grads ok)
Visa
US citizen/visa only
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Saarth Shah
Saarth Shah
Co-Founder & CEO

About the role

About Sixtyfour

Sixtyfour is a data orchestration engine for company and people intelligence. We build AI systems that gather, verify, enrich, and structure complex information about individuals and organizations across public and proprietary sources.

Our platform and API enable enterprises to design custom data pipelines that find, qualify, and act on mission-critical intelligence about people and companies.

Our Mission

To power how enterprises understand and act on people and companies with world-class intelligence.

The Role

We are hiring a Senior AI Software Engineer to design and ship production-grade AI agents that reason over complex human and organizational data.

This is not a generic LLM application role. You will build agentic systems that operate across the open web, APIs, and OSINT sources to solve high-stakes problems such as identity verification, entity resolution, and internet presence analysis for enterprise intelligence use cases.

You must have shipped real AI-first products in production. We are looking for engineers who understand how to turn large language models into reliable systems, not just prototypes.

What You’ll Actually Do

• Build agentic systems with tool calling, structured outputs, and multi-step reasoning loops

• Turn large language models into reliable production systems, not prototypes

• Engineer web intelligence pipelines that survive anti-bot systems, CAPTCHAs, rotating proxies, and dynamic sites

• Design OSINT workflows that extract signal from noisy, fragmented data

• Ship high-throughput backend systems in Python + FastAPI

• Scale workloads on AWS with Docker, queues, batch workers, and autoscaling

• Parallelize API calls safely with rate limits, retries, idempotency, and circuit breakers

• Normalize, reconcile, and deduplicate messy people and company data

• Own problems end to end, from ingestion to customer-facing impact

You will operate across AI systems, scraping infrastructure, backend architecture, and data engineering.

Who You Are

• 1–2+ years at an AI-first startup or company

• You have shipped real AI products into production

• You understand agent architectures, tool calling, structured outputs, and evaluation

• You’ve built resilient scraping systems and handled adversarial web environments

• You’re comfortable with AWS + Docker in production

• You’ve built high-concurrency IO pipelines

• You take ownership and debug systematically

You don’t just prompt LLMs. You design systems around them.

Strong Edge

• OSINT experience (intelligence, investigations, large-scale open web analysis)

• Entity resolution and probabilistic matching at scale

• Search systems, embeddings, retrieval pipelines

• Stealth browser automation and anti-bot frameworks

• Observability tooling for AI systems

This role is not suitable for new graduates.

About Sixtyfour

We build AI research agents that can discover, link, and reason over everything about people and companies. The platform turns that intelligence into automated research workflows for sales, recruiting, and marketing.

Sixtyfour
Founded:2025
Batch:P25
Team Size:8
Status:
Active
Location:San Francisco
Founders
Christopher Price
Christopher Price
Founder
Saarth Shah
Saarth Shah
Co-Founder & CEO