Backend engineer in preventative health

We're hiring a Staff Backend Engineer as a part of the founding team at Do Health - a mobile-first preventative health product co-founded by Dr Rangan Chatterjee, built as an independent startup inside Voy.

• Own major backend features end-to-end - design, build, ship, monitor, iterate. Not "contribute to" - own.
• Shape architecture. Real technical decisions, made by you, kept or changed based on what works.
• Scale our blood testing infrastructure across the UK and internationally as we expand.
• Build production AI systems - personalisation engines that act on longitudinal health data at scale.
• Improve reliability, observability, and the foundations that everything else depends on as the product grows.
• Work directly with product, design, and clinical teams. No tickets thrown over walls.

• 7–9 years of backend experience with strong fundamentals. We care more about depth than years.
• Experience at a startup or scale-up where you genuinely owned things.
• Architectural thinking. You can hold an end-to-end technical conversation about systems you've built — what trade-offs you made, what broke, what you'd do differently.
• A track record of shipping reliable systems. Not just features — the boring infrastructure that keeps them up.
• Comfort with judgement calls in ambiguous situations. Most decisions here don't have a clear right answer.
• Confident, responsible use of AI tools in your workflow. Not "vibe coding" - using them as a force multiplier where they help, ignoring them where they don't.
• Будет плюсом: Strong TypeScript / Node.js experience (it's our primary stack, but we'll happily hire someone excellent in Go, Kotlin, Python or similar); Experience scaling systems to high user volumes; Exposure to ML/AI systems in production; Healthcare or regulated-industry experience

• Genuine equity in a product with real upside, not lottery-ticket equity at a company that may never exit
• Startup velocity with grown-up backing - Voy isn't going anywhere, so you're not betting your mortgage on Series A survival
• A product that matters. Preventative health is one of the few areas where building software actually changes outcomes, not just engagement metrics.
• A high technical bar from day one. You're not joining a team that needs convincing to do things properly.
• Direct access to leadership - your work, your decisions, your name on them.