Description review

Project Lion - Lead Prompt Engineer - United States (Remote, Part-Time)

Welo Global · USA · back to the listing

HR standards

53/100

needs work

Title ↔ description

78/100

solid

Reads as

Machine Learning Engineer

87% confident

What this role officially is

data scientist — ESCO, the EU occupation classification

Data scientists find and interpret rich data sources, manage large amounts of data, merge data sources, ensure consistency of data-sets, and create visualisations to aid in understanding data. They build mathematical models using data, present and communicate data insights and findings to specialists and scientists in their team and if required, to a non-expert audience, and recommend ways to apply the data.

Also known as: data scientists, data engineer, research data scientist, data expert, data research scientist

How others title the same work

Large employers

  • Applied AI Engineer Automattic
  • Machine Learning Engineer, CX Intelligence Coinbase
  • AI Engineer - FDE (Forward Deployed Engineer) Databricks
  • AI Engineer - FDE (Forward Deployed Engineer) - U.S. Federal Sector Databricks
  • Senior AI Engineer – Notebooks Datadog

Startups

  • Attendi | Medior Machine Learning Engineer | Amsterdam, Netherlands | ONSITE (hybrid) | €6,000 - €7,000 per month | Full-time (80–100%, ~4–5 days/week) | Visa sponsorship + 30% ruling possible Attendi
  • Member of Technical Staff (applied) Anthrogen
  • Aptura AI | Full-Time | MTS (Applied AI), MTS (SWE / Product) | London | ONSITE / HYBRID Aptura AI
  • Arcforma AI (arcforma.ai) | AI Engineer (Marketing / Construction / Arcforma AI (arcforma.ai)
  • Staff AI Engineer - Agent Architecture & Behavior Artisan

What the listing never says

  • 19 bullet points. Long requirement lists deter qualified candidates, who read them as hard gates. Scope clarity
  • No pay range published. Candidates cannot tell whether applying is worth their time. Pay transparency
  • No location or timezone policy stated, so a candidate cannot tell where they may work from. Scope clarity

The listing, marked up

Nothing in the wording of this listing tripped a check. The scores above still judge how complete and coherent it is.

We are looking for an experienced Lead Prompt Engineer to guide and manage a team through the full technical migration process, transitioning templates to LLM autoraters. In this role, you will leverage advanced prompt engineering techniques and the client’s internal tools to optimize model performance, ensuring the successful integration and ongoing enhancement of AI systems. As the team lead, you will drive the strategy, mentor junior engineers, and play a key role in shaping the future of our AI-driven solutions.

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 English.

•
Location: Must be based in United States.

•
Education: 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 7 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. 

Compensation

Additional Information

Federal Law Compliance 

 

In compliance with federal law, all persons hired will be required to: 

- Verify identity and eligibility to work in the United States; and 

- Complete a required employment eligibility verification form.

Please note that in order to verify work authorization as is required by Federal law (I-9 process), all new employees must complete a live video verification with their selected IDs and provide photos of these selected IDs within their first 3 days of employment.

To know more details (Click here)

How this was produced

Highlights are found by rule, not by a model: each one is a phrase matched at a known position, and every note is a template we wrote. The two scores come from a typed-decision model (Jev) that reads the listing against the official role definition and real listings for the same role, and returns probabilities rather than prose — it never writes any of the words on this page, and never chooses what to highlight.

Deterministic penalty applied to the HR score: 12 points (from 65 before penalties). Reviewed 21 Sep 2026.