Senior Prompt Engineer

Summary

Join Postscript as a Senior Prompt Engineer and lead the development of best-in-class prompt engineering practices across our AI-powered product suite. You will set standards, guide prompt development, mentor others, and craft high-impact prompts. This player/coach role offers growth into formal leadership. You'll design, test, and refine prompts for exceptional AI features. The role requires 8-10 years of experience in marketing technology, preferably in ecommerce, AI/ML, or conversational commerce. Postscript is a high-growth, 100% remote company offering competitive compensation and benefits. The company is backed by top investors and is trusted by thousands of ecommerce stores.

Requirements

• 8-10 years of experience in marketing technology required, with a strong preference for the ecommerce sector, AI/ML, conversational commerce
• Background in Martech Sales/Solutions Engineering, Customer Success, Marketing Strategy, or Product Management
• Deep recent expertise in LLMs and prompt engineering, with hands-on experience writing prompts and executing evals
• Proven track record of shipping 0-to-1 products
• Ability to balance hands-on work with leadership responsibilities (player/coach)
• Strong collaboration and communication skills, with the ability to influence across product, design, engineering, and AI teams
• Analytical and user-centered, with a track record of using data to improve prompt effectiveness
• Growth-oriented, eager to step into greater leadership as our AI footprint grows
• Strong curiosity and learning mindset about the evolving LLM ecosystem and emerging best practices

Responsibilities

• Design, write, and optimize prompts for our LLM-powered products, ensuring high-quality, safe, and effective experiences
• Ensure prompts perform consistently across multiple models and pass P0/P1 eval standards
• Own the structure of our core agent and supervisor systems so they can extend to new channels, surfaces, and use cases
• Define and improve prompt engineering standards, best practices, and review processes
• Determine what contextual information needs to be injected into prompts and at what level of fidelity to optimize model performance across use cases - including working with engineering to design, test, and maintain structured context injection pipelines that enable high-quality outputs at scale
• Use Freeplay for prompt evals, challenger/champion testing, and optimization
• Set up and manage the process for testing challenger prompts against champion prompts in production (e.g., optimizing for revenue per subscriber while maintaining or improving unsubscribe rates and sentiment baselines)
• Operate and communicate effectively across all teams leveraging AI, serving as a unifying voice for prompt quality
• Mentor prompt engineers and cross-functional contributors (PM, design, engineering) on AI interaction design
• Drive cross-team collaboration around AI behavior, safety, and user experience standards
• Stay hands-on with product teams to ship and improve AI-powered features
• Shape the roadmap for scaling prompt engineering across products and teams
• Stay current with emerging LLM techniques, tools, and practices, and drive their adoption across the organization

Preferred Qualifications

• Entrepreneurial experience and/or technical background (engineering, data science, or similar) is a bonus
• Experience defining standards, setting a bar for excellence, and mentoring others in AI interaction design, including eval creation and iteration

Benefits

• Salary range of USD $135,000-$153,750 base plus equity (we do not have geo based salaries)
• High growth startup - plenty of room for you to directly impact the company and grow your career!
• Work from home (or wherever)
• Fun - We're passionate and enjoy what we do
• Competitive compensation and opportunity for equity
• Flexible paid time off
• Health, dental, vision insurance