Applied AI Engineer

David Joseph & Company is looking for an Applied AI Engineer in San Francisco to help own a real-time engine that generates personalized ads and continuously improves them based on performance. This role spans full-stack applied AI, from model and agent orchestration to production infrastructure that supports large-scale delivery across millions of daily interactions.

You will work on an environment where a recommendation stack and AI-generated playable ads are already live in major AI apps, backed by a proprietary ad SDK used in top App Store and Google Play releases. With architecture still to be defined, this is a build-and-ship position at an early-stage pace.

What you’ll do

• Own the engine enabling real-time personalized ads, using agents that generate on-the-fly playable mini-games, short-form video, and a range of in-between creative variants.
• Drive learning from performance by connecting creative generation to how ads perform across millions of daily interactions and millions of dollars in annualized ad spend.
• Help establish the architecture approach, since it is not defined yet.
• Build playable generation agents that take an advertiser or app brief and produce a working, on-brand HTML5 playable ad.
• Implement automated QA checks to catch broken playable builds before they reach end users.
• Build video generation pipelines, including multimodal workflows to produce short-form video ad variants across formats, hooks, and styles using frontier image and video models.
• Connect generation to the recommendation and ranking engine so each user receives creative tailored to them, then feed back engagement metrics such as engagement, CTR, installs, and ROAS.
• Provide agent infrastructure including orchestration, evals, and reliability to ensure production-grade performance at scale.

What you bring

• Applied AI experience, including building and shipping an LLM, multimodal system, or agentic system in production beyond simple API wrappers.
• Backend depth across infrastructure, data, and serving end-to-end (not only the model layer), with experience such as GCP, Redis, MongoDB, and Temporal.
• Comfort operating with ambiguity and helping define an architecture approach that is not yet established.
• A strong bias toward shipping in an early-stage company that moves quickly and iterates.

Stack and tools

• GCP, Redis, MongoDB, Temporal
• Swift, Kotlin
• React, React Native
• HTML5
• App Store, Google Play

Location, role, and compensation

• Location: San Francisco, CA (onsite)
• Employment: Full-time
• Experience: 4+ years
• Salary: USD 200,000 - 250,000 per year, plus equity
• Visa Sponsorship: Not available

Benefits

• Equity
• Ownership and a direct line to what ships

What’s already live

• A recommendation stack serving ads across millions of daily interactions, reaching tens of millions of users with millions of dollars in annualized ad spend.
• Dozens of AI-generated playable mini-game and video ads running in production inside major AI apps, built on the company’s own playable engine and editor.
• A proprietary ad SDK (Swift, Kotlin, React, React Native) in top App Store and Google Play apps.

Interview process

• Interview with the CTO
• Take-home assignment
• Work trial
• Offer