Project Lion - Senior Prompt Engineer - Japan (Remote, Part-Time)

Job description

We are seeking a **Prompt Engineer** to be responsible for the end-to-end technical migration workflow for transitioning templates to LLM autoraters. The role is required to use client’s internal tools to leverage prompt engineering techniques to maximize model performance. ### Responsibilities: - Utilize Automatic Prompt Generation (APG) tools to create baseline prompts for complex parent-child template clusters. - Run and supervise Automated Prompt Optimization (APO) tool, review the outputs, and flag when the APO reaches deadlocks or plateaus. - Manually draft, test, and refine prompts to navigate complex template architectures, overcome anti-patterns, and handle edge cases where tooling is lacking or broken. Solve edge-case scenarios by designing and refining manual prompts. - Monitor shadowbot runs to ensure sufficient disagreements (between human and LLM ratings) are registered, generated, and tracked. - Run prompt versions against established gold data to continuously measure autorater quality against the human crowd baseline, calculating accuracy metrics such as F1 scores, precision, and recall. - Draft technical launch readiness justifications (Launch Certification Documentation) for final. ### Requirement: - **Language Skills****:** Native fluency in Japanese and fluent in English. - **Location:** Must be based in Japan. - **Education****:** Bachelor’s, Master’s, or Doctorate degree in Computer Science, Data Science, Computational Linguistics, Human-Computer Interaction (HCI), Cognitive Science, or a related analytical field. - **Prompt Engineering & AI Expertise****:** At least 4 years' experience as Prompt Engineer. Proven experience tuning Large Language Models (LLMs) for strict, structured outputs, complex classification tasks, and familiarity with chain-of-thought and few-shot learning. - **Data Analysis****:** Strong proficiency in identifying error patterns, analyzing model performance, and using SQL or other data analytics tools. - **Technical Agility****:** Ability to quickly learn and master proprietary tools with minimal supervision. - **Communication****:** Excellent verbal and written communication skills. ### Optional / Preferred Skills: - Familiarity with enterprise-grade LLM interfaces like the Goose API. - Experience in AI model evaluation, data science, computational linguistics, or software engineering. - Hands-on experience with Automated Prompt Optimization (APO) systems or tuning workflows. - Linguistic expertise, including an understanding of semantics and logic.