HeartStamp is a pre-Series A startup building a first-of-its-kind generative AI platform, with an MVP launching in December. Our mission is to empower creativity by enabling users to produce unique, high-resolution images and videos that become highly resonant tactile products. The platform features a sophisticated hybrid AI engine and a growing creator economy.

We’re hiring a creative, technically skilled Prompt Engineer to push the boundaries of gen-AI. The role blends artistry with structured experimentation to develop, refine, and document prompting strategies for state-of-the-art image and video models.

Part-time contract, 10–20 hrs/week. Comp: $20–$40/hr. Salary posted is based on 15 hour a week average. 

Responsibilities: -Develop, test, and refine prompts for advanced models (e.g., Qwen-Image, Flux Dev/Kontext, Wan2.2 video, Kling2.1). -Build internal prompt libraries, style guides, and best practices for specific creative/technical outcomes. -Collaborate with engineering, design, and research to align outputs with user needs. -Probe model quirks/constraints; fine-tune prompting for consistency. -Contribute to LoRA workflows where prompting improves dataset quality. -Produce clear documentation, cheat sheets, and internal guides. -Track advances in multimodal AI, prompt engineering, and fine-tuning (e.g., LoRAs).

Required Skills & Qualifications: Strong grasp of prompt engineering for image/video; solid understanding of generative AI (diffusion, video models, VLMs) across paradigms (diffusion, transformer, closed-source APIs). Prefer at least a couple years of hands-on experience with this serios hobby or professionally

Creative problem-solver with an eye for design, aesthetics, and storytelling; excellent communicator and documenter.

Bonus -Dataset curation and LoRA training. -Python scripting to automate workflows and test prompt variations. -Experience with Hugging Face Diffusers, ComfyUI, and model APIs.

Send resume & non-AI-generated cover letter We aim to hire by September 15, 2025 This opportunity has room for growth and more hours post MVP/series A. This is a foundational opportunity with something special. We are true remote work culture with employees/contractors in 12 different countries and counting.