Freelance Senior Software Developer (Kotlin) - AI Trainer

***Please submit your CV in English and indicate your level of English proficiency.*** Mindrift connects specialists with project\-based AI opportunities for leading tech companies, focused on testing, evaluating, and improving AI systems. **Participation is project\-based, not permanent employment.** **What This Opportunity Involves** While each project involves unique tasks, contributors may: * Design and maintain automated tests to ensure the quality, performance, and reliability of Kotlin and Android applications. * Collaborate with developers to identify, reproduce, and resolve functional, performance, and UI issues across multiple environments. * Define and improve quality standards across build pipelines, ensuring smooth CI/CD integrations and release stability. * Monitor app behavior in production and use data‑driven insights to guide testing priorities and improvements. * Apply professional judgment to assess AI responses **What We Look For** This opportunity is a good fit for Senior Kotlin software developers open to part\-time, non\-permanent projects. Ideally, contributors will have: * Degree in Computer Science, Software Engineering or related fields * 5\+ years of Kotlin including coroutines, extension functions, and sealed classes. * 3\+ years of Android/JVM development experience * Familiarity with JUnit 5, Kotest, MockK, and Android testing (Espresso, Robolectric). * English proficiency \- B2 * Stable internet connection **How It Works** Apply → Pass qualification(s) → Join a project → Complete tasks → Get paid **Project time expectations** Tasks for this project are estimated to take 6\-10 hours to complete, depending on complexity. This is an estimate and not a schedule requirement; you choose when and how to work. Tasks must be submitted by the deadline and meet the listed acceptance criteria to be accepted. **Payment** * Paid contributions, with rates up to $17/hour\* * Fixed project rate or individual rates, depending on the project * Some projects include incentive payments * Note: Rates vary based on expertise, skills assessment, location, project needs, and other factors. Higher rates may be offered to highly specialized experts. Lower rates may apply during onboarding or non\-core project phases. Payment details are shared per project