Senior GenAI Software Engineer (North America)

Liftoff is a leading AI-powered performance marketing platform for the mobile app economy, seeking a Senior GenAI Software Engineer to advance their strategic initiatives in generative AI. The role involves building AI systems to optimize workflows and transform business operations, while mentoring team members and driving innovation in the ad tech industry.

Responsibilities:

• Architect and ship AI systems that generate ad creatives end-to-end - including interactive playables - combining code generation, multimodal asset generation, and runtime quality into production-grade pipelines
• Rapidly prototype against real creative problems, then take what works from proof-of-concept to production at speed
• Partner closely with creative strategists, content leads, and builders to translate craft expertise into systems that scale
• Design robust systems that handle the inherent variability of AI-generated output through thoughtful guardrails, fallbacks, and quality gates
• Build evaluation infrastructure tailored to creative output, spanning subjective quality assessment, human-in-the-loop review, and A/B testing against real ad performance
• Drive innovation by researching new model capabilities and proposing new initiatives as the frontier moves
• Mentor the team and raise the bar on engineering practices, fostering an environment of open feedback and shared learning

Requirements:

• Minimum Bachelors Degree and 5yrs of relevant experience
• Senior engineer with significant pre-LLM production experience and solid fundamentals in system design, debugging, and observability
• Strong in Python for AI/agent work and fluent in JavaScript/TypeScript for creative and playables work; HTML and gaming experience a plus
• Has shipped LLM-powered systems to production, learned the failure modes firsthand, and makes deliberate choices about what the model handles versus what belongs in code, tools, or context
• Treats evals as first-class infrastructure and brings hands-on production experience with multimodal AI, specifically image and/or video generation models, with battle-tested intuition for where they excel and where they break
• Clear communicator who collaborates well across teams and disciplines, navigating ambiguity and adapting as priorities shift
• Location: Eastern Standard Time Zone - (part of the team is located in London, U.K.)