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# Full-Stack Developer - Ai Trainer (Spain)

- **Company:** Anyone Ai
- **Location:** Sevilla, Spain
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), JavaScript (Programming Language), Artificial Intelligence, Software Bug Management, C Sharp (Programming Language), Code Coverage, Code Review, Software Debugging, Junit, Python (Programming Language), Software Engineering, TypeScript, Xunit, Pytest, Integration Tests, Code Restructuring, Golang
- **Published:** October 13, 2026
- **Apply:** https://www.buscojobs.com.es/full-stack-developer-ai-trainer-spain-en-sevilla-ID-376524770

## About the Role

Anyone AI is recruiting skilled Full-Stack Developers to work on a project with a leading AI lab.Qualifications: Advanced professional written proficiency in English3-7 years of professional software engineering experienceStrong proficiency in Python and JavaScript/TypeScript; working knowledge of Java, C#, or GoBackend or full-stack development experience in production systemsExperience with testing frameworks (e.G., pytest, Jest, JUnit, xUnit, Go testing)Proven ability to debug and navigate large, multi-file codebasesExperience with code reviews, refactoring, and production migrationsEngagement: Part-time, project-based expert evaluation workWork Type: RemoteContributors will design and evaluate realistic software engineering tasks, including bug resolution, feature implementation, refactoring/migration, and test generation.

## Description

Anyone AI is recruiting skilled Full-Stack Developers to work on a project with a leading AI lab.Qualifications: Advanced professional written proficiency in English3-7 years of professional software engineering experienceStrong proficiency in Python and JavaScript/TypeScript; working knowledge of Java, C#, or GoBackend or full-stack development experience in production systemsExperience with testing frameworks (e.G., pytest, Jest, JUnit, xUnit, Go testing)Proven ability to debug and navigate large, multi-file codebasesExperience with code reviews, refactoring, and production migrationsEngagement: Part-time, project-based expert evaluation workWork Type: RemoteContributors will design and evaluate realistic software engineering tasks, including bug resolution, feature implementation, refactoring/migration, and test generation.Work includes both creating complex coding scenarios and reviewing peer submissions for quality and accuracy.This is a project-based consultant role.Consultants will be paid on a per-project basis; hourly rates are estimates based on anticipated completion time.Consultants control their own schedule, provide their own tools, and may simultaneously provide services to other vendors/employers (subject to those vendors' allowances).Responsibilities: Contributors will:Design and implement multi-file coding tasks across bug fixing, feature development, refactoring, and testingWrite clear natural-language specifications and reference implementationsDevelop and extend unit and integration test suitesReview peer-generated tasks for correctness, clarity, and realismIdentify edge cases, ambiguities, and potential failure modesEnsure alignment between specifications, code, and expected outputsExpected Outcomes: High-quality, production-realistic coding tasksComplete and correct reference implementationsRobust test coverage and validation artifactsStructured, actionable peer review feedback#J-*****-Ljbffr