--- title: 'Junior Software Engineer at Fospha' canonical: 'https://feeny.ai/job/junior-software-engineer-fospha-london-9rpfqx8bdja3' type: 'job' last_seen: '2026-09-17' --- # Junior Software Engineer at Fospha - **Company:** Fospha - **Location:** London, United Kingdom - **Posted:** 2026-09-16 - **Last confirmed live:** 2026-09-17 - **Apply:** https://job-boards.greenhouse.io/fosphamarketing/jobs/8207846 ## 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 ## About Fospha ## Company Overview - **One-liner**: Fospha provides a full-funnel marketing measurement operating system for retail commerce, enabling brands to measure and optimise the impact of every impression and click across channels and marketplaces. - **Entity Type**: Private (backed by venture builder Blenheim Chalcot; post-seed/revenue-stage with 200+ customers) - **Headquarters**: London, United Kingdom (with offices in the US and across three continents) - **Founded**: 2014 - **Founders**: Founded by Blenheim Chalcot; led by CEO Sam Carter ## Core Business - **Primary industry**: Marketing measurement & analytics (SaaS for retail commerce) - **Target customers**: B2B – mid-market to enterprise retail brands (DTC, Amazon, TikTok Shop, etc.) such as Gymshark, Huel, and Dyson - **Mission or purpose**: To give brands the confidence to spend their full-funnel budgets and drive long-term profitable growth by providing transparent, privacy-safe, daily measurement. ## Products & Services - **[Daily MMM (Core & Beam)](https://www.fospha.com/)**: Always-on Media Mix Model delivering impression-led, full-funnel measurement at daily and ad-level granularity. Deterministic, correlative, and causal models working together (ensemble methodology). - **[Prism – Automated Budget Optimisation](https://www.fospha.com/)**: Bayesian saturation curves and marginal return forecasts that automatically shift budgets away from underperforming campaigns, improving channel efficiency. - **[Halo – Marketplace Measurement](https://www.fospha.com/)**: Incremental models that quantify how paid media drives sales across Amazon, TikTok Shop, and retail marketplaces, capturing cross-channel halo effects. - **[Glow – Brand Measurement](https://www.fospha.com/)**: Causal reasoning models to prove the revenue impact of brand-building spend. - **[Fospha AI](https://www.fospha.com/)**: In-dashboard conversational AI (marketing strategist) and MCP integration allowing teams to query data via Claude, ChatGPT, etc. - **[Science & Strategy Squad](https://www.fospha.com/about-fospha)**: Dedicated measurement experts running incrementality tests, standalone MMMs, and setting the learning agenda. ## Market Standing - **Valuation/Market Cap**: Not publicly disclosed - **Key Metric**: Over $2.5 billion in marketing spend under management (as of 2025); 200+ customers across 26 countries - **Notable Investors/Partners**: Founded and backed by **Blenheim Chalcot**; certified partner of **Meta, TikTok, and Snapchat**; customers include Gymshark, Huel, Dyson - **Growth Signals**: - 150+ employees across three continents (London, US, and other offices) - $2.5bn spend under management (up from earlier $4bn claim – likely cumulative milestone) - Acquisitions: iJento (web analytics, 2016) and another unnamed acquisition - Expanded to 200+ customers and three continents by 2025 - Launched Fospha Pro (full-funnel MTA/MMM + predictive planning) and integrated AI capabilities ## Competitive Advantages - **Glass-box transparency**: Every model layer, validation metric, and decision rule is visible to clients – no black boxes. - **Privacy-first from day one**: Moved away from pixel-based tracking over a decade ago; compliant with GDPR, CCPA, iOS14, and preparing for Google’s Privacy Sandbox. - **Ensemble methodology**: Combines deterministic click modelling, impression modelling, Bayesian saturation curves, and causal reasoning in a single always-on system. - **Daily, ad-level granularity**: Unlike legacy MMMs that run quarterly, Fospha delivers full-funnel results daily at the ad level, enabling near-real-time optimisation. - **Marketplace coverage**: Uniquely measures cross-channel halo effects on platforms like Amazon and TikTok Shop, which pixel-based tools miss. ## Strategic Focus - **Current priorities**: Deepening automation (Prism), expanding AI capabilities (Fospha AI and MCP integrations), and strengthening marketplace measurement (Halo). Scaling globally with a growing customer success and sales team. - **Direction for growth**: Continue to replace legacy attribution and MMM tools in retail commerce; add more retail media networks and sales channels; increase spend under management and headcount. ## Why Work Here - **Culture highlights**: Values include “Candour with caring”, “Seek inclusion & diversity”, “Customer at the heart”, and “Work hard, work well, work together”. Emphasis on continuous learning, professional growth, and collaborative innovation. - **Remote/hybrid/office policy**: Offices in London (HQ), Austin (US), and other locations. Roles span across Customer Success, Sales, Marketing Science, Product, and Central Operations. Likely hybrid/flexible depending on role (exact policy not specified but offices are active). - **Notable perks**: Opportunity to work with a team of 150+ data scientists and marketing experts; impact on billion-dollar spend decisions; close partnerships with major ad platforms; dynamic growth phase with significant career advancement potential. ## Sources 1. [fospha.com](https://www.fospha.com/) 2. [fospha.com/about-fospha](https://www.fospha.com/about-fospha) 3. [fospha.com/life-at-fospha](https://www.fospha.com/life-at-fospha) 4. [cbinsights.com](https://www.cbinsights.com/company/fospha) 5. [greenhouse.io (jobs page)](https://job-boards.greenhouse.io/fosphamarketing) ## Other roles at Fospha - [Graduate Data Engineer](https://feeny.ai/job/graduate-data-engineer-fospha-london-pwezgr0pzxsn) — London, United Kingdom - [Graduate Marketing Scientist](https://feeny.ai/job/graduate-marketing-scientist-fospha-london-pwtjfm4ht8fe) — London, United Kingdom - [Junior Data Scientist](https://feeny.ai/job/junior-data-scientist-fospha-london-6f379jphv4f6) — London, United Kingdom - [Data Scientist](https://feeny.ai/job/data-scientist-fospha-london-ag2m2ecg0xy0) — London, United Kingdom - [Graduate Customer Intelligence Executive - French Speaking](https://feeny.ai/job/graduate-customer-intelligence-executive-french-speaking-fospha-london-91m85e66dqth) — London, United Kingdom - [Associate Account Manager - Austin, TX](https://feeny.ai/job/associate-account-manager-austin-tx-fospha-austin-bg9e2ac4mqbk) — Austin, TX - [Graduate Technical Account Management - Austin, TX](https://feeny.ai/job/graduate-technical-account-management-austin-tx-fospha-austin-89p6j1dbd9tj) — Austin, TX - [Senior Software Engineer - Fullstack](https://feeny.ai/job/senior-software-engineer-fullstack-fospha-mumbai-xpdzwbzqgh7m) — Mumbai, India - [Graduate Customer Intelligence Executive](https://feeny.ai/job/graduate-customer-intelligence-executive-fospha-london-1qmxech6q7cv) — London, United Kingdom - [Marketing Science Lead - Austin, TX](https://feeny.ai/job/marketing-science-lead-austin-tx-fospha-austin-z5t1phs4aprj) — Austin, TX