Senior Software Engineer Node.js / AWS / React London (Hybrid, 3 days onsite) Are you the kind of Senior Software Engineer who enjoys taking something fast-and-scrappy and turning it into something scalable, elegant, and genuinely robust? This is a chance for a Senior Software Engineer to join a small, but ambitious tech-for-good / IoT startup based in the London City Centre thats building products to make sense of massive data streams. Youll be part of a tight-knit team (around ten people total, five software engineers), working on a genuinely greenfield platform with a modern stack and zero legacy The focus now is on maturing the codebase re-architecting, refactoring, testing, and scaling. As a Senior Software Engineer, youll play a key role in helping the team evolve from early-stage speed to long-term stability, with the freedom to influence both product direction and engineering qualit What youll be doing: Building and scaling a Node.js application that sits at the core of the product Designing and implementing new features for different sectors and use cases Helping drive improvements in code quality, architecture, and testing practices Working closely with product and engineering to prioritise, shape, and deliver features Introducing best practices and guiding a shift towards cleaner, more maintainable code What were looking for: Strong hands-on experience with Node.js backend software development Comfortable working across or picking up other tech as needed ie AWS, React etc (If you have experience with AWS & React, that is a bonus) Enthusiasm for writing clean, tested, production-ready code Experience (or interest) in data-heavy systems, IoT, or connected devices Ultimately, this is a backend focussed position, so as a Senior Software Engineer youll have to be comfortable with the backend nature of the role If youre a Senior Software Engineer who likes solving real problems, shaping a product, and being part of something early (and yes, you'll get equity within the business too) then this is worth a chat