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Junior Software Engineer

Fospha London🇬🇧United KingdomPosted 16 Sept 2026

Quick Overview

Seniority
Junior
Location
London, United Kingdom
Posted
4 hours ago
DynamoDBNext.jsSQLAWSGitGraphQLPostgreSQLPythonRESTReactTypeScript

Job Description

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 something broke, not just that it did
  • Curiosity about AI-assisted development and a willingness to learn spec-driven ways of working
  • Confident asking for help and pushing for clarity rather than staying blocked

Nice to have

  • Exposure to REST/GraphQL APIs
  • Familiarity with Git/GitHub and PR-based workflows
  • Some exposure to AWS or another cloud environment
  • Experience writing or maintaining automated tests
  • TypeScript experience
  • Interest in AI-assisted coding tools (we use Claude Code day-to-day)
  • Any exposure to Data Science / Data Engineering workflows

 

What we can offer you

  • A £1,000/year flexible benefits allowance to put towards private medical insurance, dental cover, a health cash plan, gym membership, extra holiday, or a pension top-up — whatever suits you
  • Access to Wellhub, giving you one membership across gyms, boutique studios, and wellbeing apps
  • 25 days' annual leave plus 8 UK bank holidays, an extra day off for your birthday, and more holiday the longer you stay (26 days after 3 years, 27 after 6)
  • Regular socials, free weekly snacks, and Lunch & Learn events at our Scale Space office, plus access to the wider Blenheim Chalcot community
  • Opportunities to travel — including to our India and North America offices
  • Life assurance worth 4x your annual salary

 

Why Fospha

  • Real end-to-end ownership. You'll ship features that drive real budget decisions at brands you'll recognise, not just tickets in isolation.
  • A published career framework. No guessing what the next level requires or when you'll get there.
  • A team that reviews each other's work properly. Code review from people who care about getting it right.
  • An AI-first operating model where lean, high-autonomy teams ship fast and learn faster — with structured mentorship from senior engineers as you build that fluency yourself.

 

Our Values and Principles

You will be able to demonstrate examples of our core principles:

  • Seek inclusion & diversity: We create an environment where everyone feels welcome, and people are encouraged to speak and be heard
  • Work Hard, Work Well, Work Together: We take responsibility for making things happen, independently and together; we help colleagues in need and close loops, making sure our work is complete and has lasting impact
  • Grow: We are proactive, curious and unafraid of failure
  • Customer at the heart: We care about the customer, feel their pain and love building product that solves their biggest problems
  • Candour with caring: We deliver candid feedback with kindness and receive it with gratitude

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