Senior Video AI Engineer — Diffusion & Production

Synthesia; United States; Remote; USD 180,000 - 240,000; Full time

Job summary

Synthesia is hiring an Applied Research Engineer to advance production‑grade foundation models for human‑centric video generation. You will own end‑to‑end research projects, from hypothesis to production impact, applying diffusion models and scalable training to deliver realistic synthetic video at scale.

The role emphasizes engineering rigor, reproducibility, and efficient inference, with impact across tens of thousands of businesses globally.

Qualifications

• Must‑have strong experience training deep learning models at scale.
• Strong Python and PyTorch skills.
• Hands‑on experience with diffusion models (image domain required; video preferred).
• Experience with large scale multi‑GPU / multi‑node training.
• Good understanding of distributed training (DDP, FSDP, DeepSpeed or similar).

Responsibilities

• Develop and scale latent video diffusion models for human‑centric video generation.
• Design conditioning mechanisms to improve control (pose, emotion, script, camera).
• Advance distributed training strategies under real compute constraints.
• Improve training stability at multi‑node scale.
• Design evaluation frameworks with automated metrics and human evaluation.
• Optimize inference for low latency, high resolution, and cost efficiency.
• Run ablations to guide high‑signal modeling decisions.
• Contribute to high engineering standards: reproducibility, CI/CD, monitoring.
• Move fast, run multiple hypotheses and focus on outcomes.

Skills

Deep learning at scale

Python

PyTorch

Diffusion models

Multi-GPU training

Distributed training

Tools

DeepSpeed

DDP

FSDP

Job description

Synthesia is hiring an Applied Research Engineer to advance production‑grade foundation models for human‑centric video generation. You will own end‑to‑end research projects, from hypothesis to production impact, applying diffusion models and scalable training to deliver realistic synthetic video at scale.

The role emphasizes engineering rigor, reproducibility, and efficient inference, with impact across tens of thousands of businesses globally.