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

2 months, 4 weeks ago
Freelance
Senior
Data Science and Analytics
Welo Global

Welo Global

Welo Global specializes in providing enterprise localization, AI training data, and multilingual content solutions, leveraging a portfolio of specialized global brands to meet diverse customer needs in the AI and language services industry.

Professional Services
Founded 1997

Description

  • Lead the end-to-end technical migration workflow for transitioning templates to LLM autoraters.
  • Use Automatic Prompt Generation (APG) tools to create baseline prompts for complex parent-child template clusters.
  • Run and supervise Automated Prompt Optimization (APO) workflows, reviewing outputs and identifying deadlocks or plateaus.
  • Manually draft, test, and refine prompts for complex template architectures, edge cases, and broken or missing tooling.
  • Design and refine manual prompt solutions for edge cases and anti-patterns that cannot be handled by automation.
  • Monitor shadowbot runs to ensure disagreements between human and LLM ratings are generated and tracked.
  • Run prompt versions against gold data to measure autorater quality against the human crowd baseline.
  • Calculate and interpret evaluation metrics such as F1 score, precision, and recall.
  • Draft technical launch readiness justifications and Launch Certification Documentation.

Requirements

  • Native fluency in Spanish and fluent English.
  • Must be based in Spain.
  • Bachelor’s, Master’s, or Doctorate degree in Computer Science, Data Science, Computational Linguistics, Human-Computer Interaction, Cognitive Science, or a related analytical field.
  • At least 4 years of experience as a Prompt Engineer.
  • Proven experience tuning large language models for strict, structured outputs and complex classification tasks.
  • Familiarity with chain-of-thought prompting and few-shot learning.
  • Strong proficiency in identifying error patterns, analyzing model performance, and using SQL or other data analytics tools.
  • Ability to quickly learn and master proprietary tools with minimal supervision.
  • Excellent verbal and written communication skills.
  • Preferred: familiarity with enterprise-grade LLM interfaces such as the Goose API.
  • Preferred: experience in AI model evaluation, data science, computational linguistics, or software engineering.
  • Preferred: hands-on experience with Automated Prompt Optimization (APO) systems or tuning workflows.
  • Preferred: linguistic expertise, including understanding of semantics and logic.

Interested in this position?

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