Senior Back-End Software Engineer Python

About JuiceLabs Where creative engineering meets applied AI At JuiceLabs, we're building vertical AI-native tools that unlock fresh insights and creative superpowers for our clients in advertising, ecommerce, and beyond. We're a nimble team of founders and builders obsessed with using AI to solve real-world problems in novel ways. As a Senior Backend Engineer at JuiceLabs, you'll be a technical leader and hands-on builder rolled into one. You'll architect and build new products from zero to one, mentor engineers, and help define our technical culture—all while working directly with our co-founders on our most strategic initiatives. You'll have genuine ownership: designing scalable distributed systems, establishing engineering best practices, leading technical decisions, and pushing the boundaries of what's possible with AI. You'll also guide and grow other engineers, helping them level up while shipping production code yourself. If you're the kind of engineer who can architect a complex system in the morning, review code and mentor a teammate at lunch, and prototype a breakthrough AI feature in the afternoon—this role was made for you. Architect and own critical backend systems and infrastructure decisions across our product suite Define engineering standards, code quality practices, and technical roadmaps Lead technical design reviews and help the team make sound architectural choices Identify technical debt, performance bottlenecks, and opportunities for improvement across the stack Build core infrastructure in Python (FastAPI, GCP/AWS, Postgres) with a focus on scalability, reliability, and developer experience Design and implement complex AI-powered features—from insights to multimodal generation systems Own critical projects end-to-end: from architecture to deployment, monitoring, and continuous iteration AI Innovation & Experimentation Build intelligent systems that go beyond simple API calls—think multi-step reasoning, tool use, and agentic workflows Evaluate and integrate new AI tools and frameworks as they emerge Mentor engineers (2-3 people initially) through code reviews, pair programming, and technical guidance Help build and scale the engineering team: contribute to hiring, onboarding, and culture-building Bridge the gap between wild ideas and production reality—help turn moonshots into concrete technical plans 6+ years of backend engineering experience, with deep expertise in Python and modern web frameworks ~ Strong systems design experience: you've built and scaled distributed systems in production ~ Mastery of cloud infrastructure (AWS/GCP), databases (SQL and NoSQL), caching, queuing, and observability ~ Expert understanding of API design, testing strategies, CI/CD pipelines, and deployment best practices ~ AI & ML Experience Hands-on experience building with LLMs and prompt engineering Bonus: experience with model fine-tuning, running local models, or MLOps practices You stay current with the AI landscape and have opinions on what works (and what doesn't) Leadership Qualities Excellent communicator who can explain complex technical concepts to both engineers and non-technical stakeholders Experience leading technical initiatives from concept to completion You know when to build for scale and when to ship an MVP High ownership and accountability—you see projects through and unblock yourself Pragmatic problem solver who balances perfectionism with shipping velocity Technical Leadership Opportunity : Help shape our engineering culture and technical direction from an early stage—your influence will compound as we grow. AI at the Frontier : Build with the latest AI technology in a production environment. Mentorship & Growth : Help build and develop a world-class engineering team while continuing to grow your own technical and leadership skills. Real Problems, Creative Solutions : Tackle meaningful challenges in ecommerce, consumer insights, and creative technology—not toy problems. Competitive Compensation : Senior-level salary, meaningful equity, and benefits that reflect your experience and impact. Send your resume, GitHub profile, LinkedIn, or portfolio to Experience: 6+ years