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

Welo Global; United States; Remote; USD 120,000 - 170,000; Full time

Job summary

Welo Global seeks a Prompt Engineer to manage the end-to-end migration workflow for transitioning templates to LLM autoraters, using client tools to optimize model performance. Responsibilities include APG/APO tooling, manual prompt drafting for complex templates, and monitoring disagreements with the LLM.

The role focuses on ensuring high-quality, structured outputs and rigorous testing against gold data. The candidate should be a German native speaker with fluent English, hold at least a

Qualifications

• Bachelor’s, Master’s, or Doctorate in Computer Science, Data Science, Computational Linguistics, HCI, Cognitive Science, or related analytical field.
• At least 4 years' experience as Prompt Engineer with LLMs for structured outputs.
• Proficiency in identifying error patterns and analyzing model performance.
• Experience using SQL or other data analytics tools.

Responsibilities

• Utilize APG tools to create baseline prompts for template clusters.
• Run and supervise APO tool; review outputs and flag deadlocks/plateaus.
• Manually draft, test, and refine prompts for complex templates and edge cases.
• Monitor shadowbot runs to ensure disagreements are tracked.
• Evaluate prompt outputs against gold data; compute accuracy metrics (F1, precision, recall).
• Draft Launch Certification Documentation for technical launch readiness.

Skills

German (native)

English (fluent)

Prompt engineering

LLM tuning

Data analysis

SQL

Education

Bachelor’s/Master’s/PhD in CS or related field

Job description

We are seeking a Prompt Engineer to be responsible for the end-to-end technical migration workflow for transitioning templates to LLMautoraters. 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.
• Manuallydraft, 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.
• Monitorshadowbotruns to ensure sufficient disagreements (between human and LLM ratings) are registered, generated, and tracked.
• Run prompt versions against established gold data to continuously measureautoraterquality 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.

Requirements

• Language Skills: Native fluency in German and fluent in English.
• Location: Must be based in Germany.
• Education: Bachelor’s, Master’s, or Doctorate degree in Computer Science, Data Science, Computational Linguistics, Human-Computer Interaction (HCI), Cognitive Science, ora relatedanalytical 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: Strongproficiencyinidentifyingerror 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.