Junior Software Engineer

Fospha is the measurement system enterprise retail and ecommerce brands run their business on. We give marketing teams one clear, daily view of what's actually working — across every channel and everywhere they sell, from their website to Amazon and TikTok Shop — down to the level of a single ad or piece of creative. It replaces guesswork and gut feel with a number marketing, finance and agencies can all trust and act on. Brands including Dyson, Gymshark, Adanola and Huel use Fospha up to 25 times a day to decide where budget should move next. We've spent over a decade building this, with more than $40 billion in marketing spend now optimised through the platform — and we're scaling fast across London, Mumbai and Austin. About the role Fospha builds the products our customers rely on every day to make multi-million dollar media decisions. You'll work across the full stack — from frontend UI/UX through to backend services, databases, and APIs in Python — alongside engineers, product managers, and AI agents as part of our AI-first operating model. You'll have the chance to make real code impact across our technical stack from day one, with senior engineers supporting you as you build ownership. This role suits someone with some hands-on software engineering experience (professional, placement, or strong personal/academic projects) who wants to go deeper. You'll take on interesting but achievable work with a supportive team structure and a company that rewards high agency with ownership. Team: Engineering Location: London What you'll do Deliver small-to-medium features independently — frontend UI in React/Next.js, backend services and APIs in Python, working with databases (Aurora PostgreSQL, DynamoDB) — with decreasing need for step-by-step direction Write clean, tested code, and grow your ownership within a system area over time Participate actively in code reviews and design discussions — giving and receiving candid feedback Own bug resolution and act on QA feedback, improving test coverage as you go Work with AI agents as part of our AI-first operating model, learning to write clear specifications that shape high-quality, AI-assisted engineering work Collaborate proactively with product managers, designers, and fellow engineers to turn requirements into working software Get involved across the full Software Development Lifecycle — planning, execution, release, and production monitoring Start building the habits of ownership: consistent delivery, low rework, and steady, visible skill growth What we're looking for Essential Some hands-on software engineering experience — internships, placements, personal/open-source projects, or up to ~2 years professional experience Working knowledge of React.js or Next.js, a solid foundation in Python, and some exposure to databases (SQL or NoSQL) Comfortable being reviewed and iterating on feedback quickly Genuine attention to detail and a real interest in why…