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25Madison is a New York-based venture studio and investment platform that builds and invests in companies across healthcare, supply chain, industrials, and AI-powered business software. We're seeking a product-minded engineer to join our studio and work hands-on across multiple portfolio startups.
In this role, you'll report directly to our CTO and take products from idea to production. You'll work closely with founders, designers, and customers to understand workflows, challenge assumptions, and determine what matters most. Your responsibilities include:
• Taking early concepts and customer problems through to prototypes and first versions, then improving them as the business grows
• Working directly with founders and customers to understand their needs and help shape product direction
• Building across the full stack: interfaces, backend services, data models, integrations, and AI-enabled workflows
• Owning testing, deployment, and production reliability
• Using AI coding tools and agents as a core part of your workflow while maintaining accountability for architecture, security, and code quality
• Making technical decisions about what to build and when to build less
This is a high-agency role where you'll be involved in key decisions: which customer to serve, what to validate first, where to invest engineering time, and when to scale. You'll have the opportunity to build across multiple companies, take meaningful ownership early, and see how your product and engineering decisions affect the business.
REQUIREMENTS:
• Proven track record of shipping production software that people use
• Ability to take meaningful work from initial conversation through deployment without requiring detailed specifications
• Strong engineering fundamentals across frontend, backend, APIs, databases, and cloud infrastructure
• Ability to debug unfamiliar systems, make sound technical tradeoffs, and keep solutions simple
• Established AI coding workflow: extensive use of AI tools for building, testing, debugging, and refactoring; ability to direct them, recognize weak output, and verify results
• Product empathy and judgment: care about whether the product makes someone's job easier, notice confusing interactions, ask good questions, and use customer feedback to drive changes
• High agency and clear communication: identify what needs to happen, propose a path forward, move it forward, surface blockers early, and take responsibility for outcomes
• Startup experience is helpful but not required; evidence of what you can build and how you think matters more than degree, title, or years of experience
