# Lead AI Engineer at Sphere

- Company: Sphere
- What the company does: Manage VAT, GST, and sales tax worldwide with Sphere’s global tax compliance software. Automate registration, calculation, and filing seamlessly. Backed by Y Combinator, a16z and Felicis.
- Company website: https://www.getsphere.com/
- Type: Startups (AI role)
- Level: Senior
- Location: San Francisco HQ
- Work setup: On-site
- Pay: $250K to $280K base salary per year (USD)
- Posted: 2025-10-07
- Apply by: 2026-10-08
- Apply: https://jobs.ashbyhq.com/sphere/4e3c5943-bd07-4ce1-8e13-68b00221d0b7
- Page: https://www.1752.vc/careers/jobs/sphere-lead-ai-engineer/

## About the role

You'll lead development of TRAM, our proprietary AI reasoning model that reads and interprets global trade law. This isn't a lookup problem, it's a reasoning problem — and it only became solvable with LLMs. You'll build the data pipelines that ingest legal sources, the model stack that produces structured evidence, the evaluation frameworks that measure accuracy, and the fine-tuning loops that improve performance.

## What they're looking for

- Prior experience building AI enabled products, particularly RAG systems
- Experience fine tuning base models, ideally via RFT
- Willingness to dive into tax technical problems - if you aren’t willing to dive deep on how the model should reason through the tax research process you won’t be effective
- A strong understanding of how LLMs and reasoning models function

Tags: Engineering