Backend Engineering Specialist - Freelance AI Trainer Project

Invisible Technologies Inc.; United States; Remote; USD 11,000 - 90,000; Part time

Job summary

Invisible Technologies is seeking a Backend Engineering Specialist – AI Trainer to help shape the future of AI training data. This mid-senior contractor role is remote in the United States, offering exposure to Python/Java/Go/C++, Django/Spring/Express, and Docker/Kubernetes in distributed systems.

You will review AI-generated code, assess logic, document error patterns, and collaborate on prompts, evaluation methods, and engineering guidelines to improve model outputs and tooling.

Qualifications

• Strong experience with backend languages Python/Java/Go/C++.
• Experience with web frameworks Django/Spring/Express and databases (SQL/NoSQL).
• Familiarity with API design, distributed systems, cloud services, and containerization.

Responsibilities

• Review and annotate AI-generated code for correctness and quality.
• Assess outputs for logical and structural soundness and identify error patterns.
• Document and report issues to refine prompts, evaluation methods, and guidelines.
• Collaborate with team to improve backend tooling and data pipelines.

Skills

Python

Java

Go

C++

Tools

Django

Spring

Express

SQL/NoSQL databases

Docker

Kubernetes

APIs design

Distributed systems

Cloud services

Job description

Are you an experienced Backend Engineer eager to shape the future of AI? Large-scale language models are evolving rapidly, moving beyond simple chatbots into powerful engines of research, learning, and applied problem-solving. With high-quality training data, tomorrow’s AI can provide more accurate, practical, and innovative solutions across industries. That training data begins with you—your expertise will help power the next generation of AI.

We’re looking for a highly skilled Backend Engineering specialist who can bring technical depth, coding expertise, and architectural insight to training data. You’ll work with cutting-edge AI tools, evaluate and refine code outputs, and provide expert feedback on correctness, efficiency, scalability, and best practices in backend engineering.

On a typical day, you will review and annotate AI-generated code, assess outputs for logical and structural soundness, identify and document error patterns, and collaborate with our team to refine prompts, evaluation methods, and engineering guidelines.

Proficiency in backend technologies is required, including strong experience with languages such as Python, Java, Go, or C++; frameworks such as Django, Spring, or Express; and databases (SQL/NoSQL). Experience with API design, distributed systems, cloud services, or containerization (Docker/Kubernetes) is a strong plus. Clear communication skills, problem-solving ability, and attention to detail are essential.

We offer a pay range of $8 to $65 per hour, with the exact rate determined after evaluating your experience, expertise, and geographic location. Final offer amounts may vary from the pay range listed above. As a contractor you’ll supply a secure computer and stable internet connection; company-sponsored benefits such as health insurance and PTO do not apply.

Job title: Backend Engineering Specialist – AI Trainer
Employment type: Contract
Workplace type: Remote
Seniority level: Mid-Senior