Senior Full Stack Engineer (Python / FastAPI / AI)

About Sourceful

Sourceful is a technology company headquartered in Manchester, England. Its platform helps brands design logos, shelf-ready packaging and visual assets across sectors including food and beverage, beauty, electronics, fashion, and home. Sourceful's agentic platform guides users from ideation to print-ready artwork files that can be sent directly to suppliers. Sourceful’s users come from design and non-design backgrounds.

Sourceful has also developed a state of the Image Generation and Editing model, Riverflow, which is a multi-purpose model that can be used by developers via API. The company is backed by Index Ventures, Coatue Management, and Eka Ventures.

About the Role

Sourceful is looking for a Senior Fullstack Engineer with a strong foundation in scalable core systems, deep Python experience, and enough frontend fluency to help craft a seamless, AI-enabled product. You’ll work close to our emerging AI features, shaping services that carry real-world load and help millions turn ideas into reality.

Key Responsibilities

• Own and deliver scalable core systems while collaborating closely across the stack to ensure seamless frontend experiences.
• Design, build, and maintain systems and APIs that power Sourceful’s AI-driven design tools
• Shape APIs that are clean, scalable, and easy for frontend and external developers to use
• Optimize system performance and reliability across the stack
• Understand how to solve spiky traffic challenges includes queues, rate limits and auto-scaling
• Collaborate closely with design and frontend teams to ship fast and iterate often
• Tackle complex technical challenges, from prompt chaining to real-time rendering

Qualifications

Technical Skills

• 5+ years of engineering experience in core systems engineering experience
• 4+ years of hands-on Python experience, including production systems you owned end-to-end
• Professional experience with FastAPI in production, ideally supporting 10k+ users or comparable load
• Comfortable working close to ML/AI features and integrating with model-driven services
• Intentionality with AI/dev tools (e.g., Copilot, Cursor, Devin) and when to override them
• Proven ability to deliver complex features autonomously in ambiguous, high-growth environments
• Nice to have: experience with GPUs, model fine-tuning, or applied Transformer-model workflows

Soft Skills

• Systems thinker who values clarity, simplicity, and performance
• Sharp design sensibility and obsessive attention to detail
• Fast, autonomous builder who thrives in ambiguity
• Strong communicator who enjoys sharing work and mentoring others
• Mission-aligned: Passionate about solving hard problems with elegant, intuitive interfaces

What You’ll Get

• Building a World-class Product with a small but mighty A-player team
• Mentoring and coaching from Cofounder & CEO
• Access to latest AI tools for coding
• Pension Plan and Private Health Insurance
• 25 vacation days per calendar year
• Performance Bonuses
• Work arrangement: Hybrid, avg. 3 days/week in our lovely Hub in Manchester Central