Prompt Engineer

At Pencil, we are driving innovation in advertising technology through our state-of-the-art SaaS product, which harnesses Generative AI to redefine content creation. Our mission is to make AI the default in advertising without replacing creative people. To achieve this, we need to make sure that our technology isn’t just in the hands of big brands - we need to try to help small businesses and creative individuals too. We’re looking for a Prompt Engineer to shape how our clients create with AI. You’ll design, build, and refine the prompts, agents, and workflows that power Pencil’s creative experiences by helping brands and creators generate content that feels both original and on-brand. You’ll work closely with our Creative, Product, and AI teams to translate client needs into usable, scalable AI workflows that drive adoption and demonstrate Pencil’s best-in-class creative capabilities. You’ll be part experimenter, part problem-solver, and part storyteller. You will use prompts not just to produce results, but to shape how people create. Key responsibilities: Design and refine prompts, workflows, and AI agents that enable clients to generate high-quality creative outputs at scale.Collaborate with the Delivery teams to understand client goals and translate them into prompt-based solutions.Build reusable prompt frameworks and templates for recurring use cases.Test, evaluate, and iterate on prompts and agents to improve output quality, efficiency, and user satisfaction.Define and document best practices for prompt creation, testing, and deployment within Pencil’s platform.Partner with Product and Engineering teams to identify new capabilities or improvements based on client feedback.Contribute to internal playbooks, demos, and guides that showcase how to get the most out of our agents and AI tools. Your background:Hands-on experience crafting prompts and workflows for text, image, or video generation (e.g., for LLMs or multimodal models).Proven ability to turn creative briefs or client needs into AI-driven creative workflows.Strong understanding of how tone, structure, and context influence AI outputs.Comfort working with creative teams to refine ideas collaboratively.Analytical mindset for testing and iterating based on output quality and user feedback.Experience using or exploring prompt-based tools and GenAI platforms.Excellent communication skills and the ability to explain complex AI concepts simply and clearly. You’ll Thrive Here If You…You love experimenting and testing multiple ways to say one thing until the AI gets it just right.You’re curious about how humans and machines collaborate to create.You get satisfaction from designing workflows that make others more creative and efficient.You’re detail-obsessed but flexible when the real world needs fast iteration.You enjoy shaping emerging best practices in a space that’s moving fast and evolving daily.You’re excited by client-facing work that blends creativity, experimentation, and real-world impact. KPIs & Success MeasuresAgent adoption rate: Growth in the number of active clients using Pencil-built agents and workflows.Creative generation volume: Increase in the number of generations produced through agents you’ve developed.Output quality: Improvement in client satisfaction scores or internal quality benchmarks.Efficiency: Reduction in time-to-first-output or manual setup time for client projects.Knowledge sharing: Contributions to prompt libraries, playbooks, and team enablement materials.Benefits:25 days PTO plus public holidays, although we operate a Flexible Time Off schemeHealth insurance / private medical coverMonthly stipend towards wellness, fitness, and learning and developmentRemote - work from anywhere in your home countryEnhanced parental leave policies, whether you become a parent through birth, adoption or surrogacyAccess to our Pencil office in The Shard, London for our UK employeesFlexible working hours