AI Research Engineer

Company: PostHog

Job Category: AI Engineering / Research / LLMs / Product

Contract Type: Full-Time, Permanent

Location: Remote — Worldwide (GMT +2 to GMT -8)

Salary: Via public calculator at posthog.com/careers

Application Link: https://posthog.com/careers (listed as "AI Research Engineer" on the PostHog AI Team)

Posted: Live May 14, 2026

Job Description: PostHog is building PostHog AI — an AI-powered analyst that answers product questions, helps users find useful session recordings, and writes custom SQL queries. You'll work on the PostHog AI Team to push the frontier of what's possible with AI-powered product analytics, applying the latest research to real user problems at scale.

Key Responsibilities:

• Research and develop AI capabilities powering PostHog AI (the AI analyst product)
• Work on LLM integration, prompt engineering, evaluation frameworks, and model fine-tuning
• Build AI features end-to-end in production — not just prototype them
• Collaborate with product engineers to integrate AI capabilities across PostHog's platform
• Track the latest AI/ML research and evaluate applicability to PostHog's products
• Contribute to evaluation benchmarks and quality measurement for AI features

Requirements:

• Strong AI/ML background with production experience deploying LLM-based features
• Experience with prompt engineering, fine-tuning, RAG systems, and model evaluation
• Full-stack engineering capability — can build the product around the AI, not just the AI itself
• Strong writing skills for PostHog's async documentation-heavy culture
• Genuine interest in product analytics, developer tools, or SaaS intelligence