AI Engineer/ML Engineer - Senior Developers - AI Training - Sheffield, UK

prolificacademicltd; United States; Remote; USD 83,000 - 110,000; Full time

Benefits offered by this job

Fully remote

Flexible hours

Fast onboarding

Job summary

prolificacademic ltd is seeking a senior AI/ML engineer for a contract role focused on training and evaluating large language models. Work consists of one-hour focused sessions within an expert contributor network, with researchers paying up to $80 per hour.

An initial 10–15 minute skills assessment gates entry, ensuring high standards of expertise. Responsibilities include reviewing explanations of architectures and loss functions, auditing training code and notebooks for efficiency, and

Qualifications

• Bachelor's/Master's/PhD with ML focus in CS/AI related field.
• Hands-on experience building, deploying, or fine-tuning ML models.
• Hands-on with neural architectures like Transformers, CNNs, RNNs.
• Experience with prompt engineering, RAG, or RLHF.
• Ability to audit model logic and detect data contamination.

Responsibilities

• Review explanations of model architectures and loss functions for accuracy.
• Audit ML code, training loops, and evaluation pipelines for efficiency.
• Provide high-quality feedback for RLHF-aligned models.
• Assess chain-of-thought prompts and detect reasoning failures.
• Run benchmarking against defined metrics and taxonomies.

Skills

Transformers

Neural networks

Prompt engineering

RLHF

PyTorch

TensorFlow

Python

Model evaluation

Audit ML code

ML deployment

Education

PhD in CS/AI/related quantitative discipline

Masters in related field

Bachelor's in CS/AI/related field

Tools

PyTorch

TensorFlow/Keras

Hugging Face Transformers

AWS SageMaker

GCP Vertex AI

Weaviate / Pinecone

Job description

Role overview

This is a senior-level contract opportunity for experienced AI and machine learning engineers to contribute to the training and evaluation of large language models. Selected candidates join an expert contributor network and complete paid technical tasks that draw on deep production-grade ML expertise. Work is structured as one-hour focused sessions, with researchers typically paying up to $80 per hour for this specialist input, and an initial 10–15 minute skills assessment gates entry.

Responsibilities

• Review AI-generated explanations of model architectures, loss functions, and backpropagation to confirm technical accuracy
• Audit ML code and notebooks, including training loops, preprocessing scripts, and evaluation pipelines, for efficiency and correctness
• Supply the high-quality human feedback used to align models with intent, safety, and helpfulness through reinforcement learning workflows
• Critically assess how AI systems handle complex chain-of-thought prompts and pinpoint where reasoning breaks down
• Run comparative benchmarking between competing model outputs against defined technical taxonomies and performance metrics

Requirements

• Bachelor's, Master's, or PhD in Computer Science, Artificial Intelligence, Robotics, or a related quantitative discipline with an ML focus
• Hands-on production experience building, deploying, or fine-tuning ML models
• Professional-level command of neural network architectures such as Transformers, CNNs, and RNNs, plus associated optimization techniques
• Practical experience with prompt engineering, retrieval-augmented generation (RAG), or reinforcement learning from human feedback (RLHF)
• Ability to audit complex model logic, spot training-data contamination, and evaluate mathematical proofs behind ML algorithms
• Sharp attention to detail when identifying hallucinations, biased outputs, or logical failures in AI-generated technical content

Nice to have

• Expert proficiency with PyTorch or TensorFlow/Keras
• Advanced Python (NumPy, Pandas, Scikit-learn) and working knowledge of Hugging Face Transformers
• Exposure to AWS SageMaker, Google Cloud Vertex AI, Weights & Biases, or LangChain
• Familiarity with vector databases such as Pinecone, Milvus, or Weaviate for RAG evaluation

Benefits and work setup

• Fully remote with flexible hours and no minimum commitment
• Onboarding typically completed within 15 minutes of passing the assessment
• Hourly rates up to $80, with task descriptions, time estimates, and pay shown before acceptance
• Location: Sheffield, United Kingdom