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Freelance Kotlin Developer (m/f/d)

No longer accepting applications

Project specification

Project duration
Period 22 Dec 2025 - 14 Mar 2026
Project capacity
Capacity from 5%
Daily rate range
Daily rate 128 - 384€
Remote work ratio
Remote from 95%
Required languages
Languages
English (Advanced)

Project expertise

Industries
Information Technology
Areas
Information Technology Research and Development

Description

For an AI lab we are looking for Kotlin Developer to train an AI model (Large Language Model - LLM).

You help AI to make sense of the world. As a consultant, you may be invited to take part in online projects to train the model in your domain of expertise.

This flexible role accommodates both experts seeking part-time engagement (minimum a few hours/week) and those interested in full-time opportunities.

  • Code generation and code review
  • Prompt evaluation and complex data annotation
  • Training and evaluation of large language models
  • Benchmarking and agent-based code execution in sandboxed environments
  • Working across multiple programming languages
  • Adapting guidelines for new domains and use cases
  • Following project-specific rubrics and requirements
  • Collaborating with project leads, solution engineers, and supply managers on complex or experimental projects

Requirements

  • You hold a Bachelor's or Master’s degree in Computer Science, Software Engineering, Software Development, Computer Engineering, Information Technology, or a related field
  • You have at least 3 years of professional iOS/macOS development experience
  • Your English is advanced (C1) or above
  • Mid-level proficiency in Swift 5.9+, including SwiftUI, Combine, async/await, and the concurrency model
  • Hands-on experience with testing frameworks (XCTest, Quick/Nimble) and UI automation testing
  • Proficiency with Xcode, Swift Package Manager, and CI/CD tools (Fastlane, GitHub Actions, Xcode Cloud)
  • Experience with App Store deployment and monitoring tools (Crashlytics, Firebase)
  • Strong understanding of architectural patterns (MVVM, Clean Architecture) and performance optimization (ARC, Instruments)
  • Experience integrating AI/ML capabilities (Core ML, Vision, Create ML)
  • Practical use of AI-assisted tools for code generation, refactoring, and test automation
  • Strong skills in crash analysis, memory debugging, and performance profiling
  • You are ready to learn new methods, able to switch between tasks and topics quickly, and sometimes work with challenging, complex guidelines.

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Frequently asked questions

The project preferably starts in December 2025 and is planned to end in March 2026 (3 months).

The project requires a commitment of 5 - 100% capacity (full-time).

The project offers 95 - 100% remote work.

The project offers a daily rate of 128 - 384€ which breaks down to an hourly rate of 16 - 48€/h.

The project requires the following languages: English (Advanced).

The project is related to the following industry: Information Technology.

The project covers the following business areas: Information Technology and Research and Development.

Yes! Recommend a freelancer for the project and earn 30% of FRATCH's profits every time they get placed — for the duration of that project. Simply share your invite link with a colleague to get started.

To apply for the project, click the Apply button on the project page to submit your profile for review. We will forward your resume to the client and get back to you within a few days.

Published:·Updated:

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