Senior Prompt Engineer (Portugal) | LLM Performance Expert

Welo Global; United States; Remote; USD 78,000 - 112,000; Full time

Job summary

Welo Global in Portugal seeks a Prompt Engineer to lead the end-to-end migration workflow for transitioning templates to LLM autoraters, leveraging internal tools to maximize model performance.

You will run APG and APO systems, draft and refine prompts for complex template architectures, monitor edge cases, and quantify accuracy against gold data.

Strong Portuguese and English, a CS/DS-related degree, and 4+ years in prompt engineering are required.

Qualifications

• 4+ years of experience as Prompt Engineer.
• Proven experience tuning LLMs for structured outputs.
• Proficiency with SQL or related data analytics tools.
• Native Portuguese with fluent English.

Responsibilities

• Use APG tools to generate baseline prompts for template clusters.
• Run APO tool, review outputs, and flag deadlocks or plateaus.
• Draft and refine prompts to handle edge cases and anti-patterns.
• Monitor shadowbot runs and track disagreements between human and LLM ratings.
• Evaluate prompts against gold data, measuring accuracy metrics (F1, precision, recall).
• Prepare Launch Certification Documentation for readiness.

Skills

Portuguese (native)

English (fluent)

Data analysis

SQL

Communication

Fast learner

Prompt engineering

Education

Bachelor’s/Master’s/Doctorate in CS/DS/Computational Linguistics/HCI

Tools

APG tools

APO systems

Goose API

Job description

Welo Global in Portugal seeks a Prompt Engineer to lead the end-to-end migration workflow for transitioning templates to LLM autoraters, leveraging internal tools to maximize model performance.

You will run APG and APO systems, draft and refine prompts for complex template architectures, monitor edge cases, and quantify accuracy against gold data.

Strong Portuguese and English, a CS/DS-related degree, and 4+ years in prompt engineering are required.