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Backend Engineering Specialist - AI Trainer

Remote, Global·Full-time·Added over a year ago

This job was published a year ago

Invisible Technologies

42 open roles

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Overview

Job details

US$8 - US$65 an hour
Gross, as stated in the ad.
Full-time hours
Per the ad.
Fully remote
Per the ad.

Requirements

Have the right to work in Spain
Invisible Technologies doesn't mention sponsorship in the ad.
Work in English
English is required, per the ad.

Pay & benefits

What you'll get

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.

Requirements

What we're looking for

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.

Ready to channel your backend engineering expertise into building the AI tools of tomorrow? Apply today and help train the model that will support developers and organizations worldwide.

The role

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.

What you'll do

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.

How you'll work

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

About Invisible Technologies

Invisible Technologies is an applied AI services and operations company that trains, evaluates, and deploys AI models for enterprises. Its website states it has trained over 80% of the world's leading AI models and offers a platform spanning data processing, expert sourcing, model evaluations, and governed AI agents, serving industries such as banking, healthcare, insurance, life sciences, and the public sector. The company was established in 2015 and reports a team of 250+ people, with recognition including a 2024 Deloitte Technology Fast 500 listing.

Founded: 2015
Employees: 250+
Website: invisible.co

Good to know if you are moving

Hires remote AI Trainer roles in Spain across dozens of languages, including Basque, Arabic, Chinese, Portuguese, and many others
Offers freelance, project-based AI trainer engagements, such as the 'Business and Management Specialist – Freelance AI Trainer Project'
Recruits subject-matter experts from diverse professional fields — including neuroscience, law, software development, HR, and finance — to work as AI trainers
Also hires specialist roles such as 'Domain Advisor Consultant (Subject Matter Expert)' for on-demand expert projects

All open roles at Invisible Technologies