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Senior Prompt Engineer

Remote from Spain·Part-time·Added 7 months ago (last checked 21 Oct)

Welocalize

77 open roles

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Our summary

Work mode: Remote from Spain
Contract: Freelance, part-time hours
Spanish: Fluent
English: Required
Experience: 4+ years
Education: University degree

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Skills

Requirements

What we're looking for

Language Skills: Native fluency in Spanish and fluent in English.
Location: Must be based in Spain.
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.

Nice to have

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.

The role

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.

What you'll do

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.

About Welocalize

Welocalize is a global leader in language services and localization technology, helping brands adapt their content, products, and AI models for international markets. With a workforce of over 500,000 linguists and subject matter experts worldwide, the company provides translation, transcreation, data annotation, and AI training services to clients across industries such as technology, life sciences, and media. Headquartered in Frederick, Maryland, USA, Welocalize operates globally with a strong focus on AI-driven localization solutions.

In Spain, Welocalize has a significant presence, offering numerous remote and hybrid roles for Spanish, Catalan, Basque, and Galician speakers. The company is a major employer for international professionals, particularly those with multilingual skills, as it frequently hires for AI training, quality evaluation, and localization projects. Work culture is remote-friendly and project-based, making it an attractive option for professionals seeking flexible work arrangements while contributing to cutting-edge AI and localization initiatives.

Industry: Localization Tech
Founded: 1997
Employees: 500,000+
Headquarters: Frederick, USA

Good to know if you are moving

Welocalize offers fully remote roles, allowing international professionals to work from Spain without relocation.
The company frequently hires for AI training and data annotation projects, which are ideal for linguists and tech-savvy professionals.
Spanish, Catalan, Basque, and Galician speakers are in high demand for various localization and quality assurance roles.
Welocalize provides flexible freelance and contract opportunities, making it suitable for those seeking portfolio careers.
The company has a global presence with clients in major industries, offering exposure to international projects.

All open roles at Welocalize