Mobile Game Developer

About the Role

We are looking for mobile game developers to help train and evaluate AI models on mobile game development. You will design and review game features in Unity and C#, optimise performance across devices, and assess AI-generated gameplay code.

Key Responsibilities

• Design, build and review mobile game features in Unity and C#.

• Optimise game functionality and performance across a range of devices and platforms.

• Evaluate AI-generated gameplay code and scene setups for correctness and quality.

• Write reference implementations and brief technical explanations.

• Take part in brainstorming on new mechanics and features.

• Give structured written feedback on model outputs.

• Follow project guidelines, take part in calibration and review sessions, and incorporate feedback to keep quality consistent.

Who We're Looking For

Required Qualifications

• Expert-level proficiency with Unity and C#.

• Strong understanding of core game design principles and player experience.

• A portfolio of completed mobile game projects.

• Fluent written English.

• Reliable, detail-oriented, and able to work independently and meet deadlines in a remote setting.

Preferred Qualifications

• Cross-platform build experience (iOS and Android).

• Live-ops or analytics experience.

• Experience with 2D engines such as Cocos2d-x.

Rights, Confidentiality and Data Handling

• Submit only work that you created yourself or that you have the right to share.

• Do not submit material covered by an employer, client or third-party confidentiality agreement, or material you have no right to share.

• Do not submit export-controlled, military or defence-related technical data.

• Remove credentials, secrets and personal data from anything you submit.

• Rex may ask for evidence of ownership or licence, may verify submissions, and may reject or remove any submission.

Legal and Compliance Notice

• All content you submit must be lawful, and you must have the right to share it.

• Do not submit confidential or proprietary material belonging to an employer, client or third party, or personal data without a lawful basis.

• Rex may verify identity, credentials, ownership and licensing; may reject or remove any submission; and may report unlawful submissions to the relevant authorities.

• Engagement and payment are subject to successful verification and to applicable sanctions, export-control, tax and employment laws.

• The contractor agreement will set out ownership and licence terms for the work you deliver (to be confirmed by Rex Legal).

Compensation

USD $50–120 per hour, adjusted by country of residence.