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Mathematics Specialist (Fluent in Spanish - Spain) - Freelance AI Trainer Project

Remote from Spain·Added 23 days ago

Invisible Agency

11 open roles

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Overview

Job details

US$65 an hour
Gross, as stated in the ad.
Freelance contract
Per the ad.
Fully remote
Per the ad.

Requirements

Have the right to work in Spain
Invisible Agency doesn't mention sponsorship in the ad.
Speak fluent Spanish
Listed as a requirement in the ad.
Work in English
English is required, per the ad.
Master's degree
“A master's or PhD in mathematics or a closely related quantitative field is ideal” — per the ad.

Pay & benefits

What you'll get

We offer a pay range of $6-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 high‑speed internet; company‑sponsored benefits such as health insurance and PTO do not apply.

The role

Are you a mathematics expert fluent in Spanish (Spain), eager to shape the future of AI? Large‑scale language models are evolving from clever chatbots into powerful engines of scientific discovery. With high‑quality training data, tomorrow's AI can democratize world‑class education, keep pace with cutting‑edge research, and streamline academic work for students and professionals everywhere. That training data begins with you-we need your expertise to help power the next generation of AI.

We're looking for mathematics specialists who live and breathe algebra, calculus, number theory, linear algebra, differential equations, statistics, geometry, mathematical logic, and discrete mathematics. You'll challenge advanced language models on topics like real and complex analysis, optimization theory, mathematical proofs, set theory, probability distributions, cryptographic algorithms, and applied mathematics-documenting every failure mode so we can harden model reasoning.

On a typical day, you will converse with the model on classroom problems and theoretical mathematics questions, verify factual accuracy and logical soundness, capture reproducible error traces, and suggest improvements to our prompt engineering and evaluation metrics.

A master's or PhD in mathematics or a closely related quantitative field is ideal; peer‑reviewed publications, teaching experience, research in pure or applied mathematics, or hands‑on experience with mathematical modeling signal fit. Clear, metacognitive communication-"showing your work"-is essential.

Ready to turn your mathematics expertise into the knowledge base for tomorrow's AI? Apply today and start teaching the model that will teach the world.

Job title

Job title: Mathematics Specialist (Fluent in Spanish - Spain) - AI Trainer
Employment type: Contract
Workplace type: Remote
Seniority level: Mid‑Senior Level

About Invisible Agency

Invisible Agency is a technology company that provides AI-driven business process outsourcing and automation services. It operates a global network of freelance and full-time professionals who train AI models, handle complex data tasks, and support enterprise clients. The company is headquartered in New York, USA, and positions itself as a leader in the 'invisible' services economy, combining human expertise with AI tools to deliver scalable solutions.

In Spain, Invisible is actively hiring freelance AI trainers and language specialists for projects involving Spanish, Catalan, Galician, Occitan, and Ukrainian languages, as well as STEM and coding expertise. These roles are remote-friendly and offer flexible, project-based work, making them attractive to international professionals with linguistic or technical skills. The company's Spain presence is primarily remote, with no physical offices listed, and it values diverse, multilingual talent to improve AI models for global markets.

Industry: AI Services
Founded: 2019
Employees: 1,000–5,000
Headquarters: New York, USA
Website: invisible.co

Good to know if you are moving

All Spain-based roles are freelance and remote, allowing flexibility for international professionals.
The company hires language specialists for Spanish, Catalan, Galician, Occitan, and Ukrainian, making it a good fit for multilingual candidates.
Roles are project-based, often requiring no relocation, which is ideal for those already in Spain or planning to move.
Invisible is known for its AI training projects, offering opportunities to work on cutting-edge AI model development.
The company has a global presence, with a diverse team and clients across multiple industries.

All open roles at Invisible Agency