Senior Software Engineer - Fullstack

Liberis; Mumbai; On-site; INR 4,000,000 - 6,500,000; Full time

Benefits offered by this job

Competitive salary

Be part of a leading global venture-

Learning & development

Flexible benefits

25 days paid holiday

Job summary

Fospha, a fast-growing tech company, is hiring a Senior Software Engineer to build the products powering real-time analytics and GenAI tools. You will work across the full stack—from modern frontend experiences with React.js/Next.js to scalable Python-based microservices—and help shape system design as we scale globally.

You will collaborate with AI agents and cross-functional teams in an AI-first operating model, owning end-to-end features, writing clean, tested code, and driving engineering

Qualifications

• 5+ years of professional experience as a full stack / senior software engineer.
• Strong front-end with React.js or Next.js.
• Experience building Python-based microservices.
• Experience contributing to system design and infrastructure decisions.
• Ownership mindset and ability to ship end-to-end features.
• Comfortable working in agile environments.

Responsibilities

• Design, build, and maintain full-stack features - from frontend UI/UX through to backend services and APIs in Python.
• Contribute to system design and infrastructure decisions, helping evolve our technical foundations as we scale.
• Get involved across the full Software Development Lifecycle, from planning through production release and monitoring.
• Write clean, well-tested, maintainable code, and champion good engineering practices.
• Collaborate closely with product managers, designers, and engineers to translate requirements into working software.
• Build and consume APIs (REST/GraphQL) that connect frontend experiences to backend services.
• Work with AI agents as part of our AI-first operating model to shape high-quality engineering work.
• Take ownership of quality, performance, and reliability of shipped features.
• Participate in code reviews and provide constructive feedback.
• Stay curious about new tools and technologies, including Data Science opportunities.

Skills

Full stack

React.js

Next.js

Python

Microservices

System design

REST/GraphQL

Agile

Code reviews

AI awareness

Job description

• Are you excited by the idea of helping scale a fast‑growing tech business across London, Mumbai and Austin?
• Do you want to contribute towards building cutting‑edge automation systems that power real‑time analytics and GenAI tools?

If so, we’d love to hear from you!

About Fospha:

Fospha is dedicated to building the world's most powerful measurement solution for online retail. For over a decade, we've helped teams make smarter decisions with full‑funnel marketing insights, forecasting, and optimisation. With Fospha, every team moves faster and grows smarter. Trusted by over 200 leading brands across three continents, including Huel, Oh Polly, and Represent, Fospha manages $2.5 billion in annual ad spend.

Founded and backed by Blenheim Chalcot, Fospha combines startup agility with the scale, expertise, and support of one of the world’s leading venture builders.

Ready to make your mark? Let’s go!

The Role

As a Senior Software Engineer, you'll build the products our customers rely on every day to make multi-milliondollar media decisions. You'll work across the full stack - from crafting responsive, intuitive frontendexperiences through to designing and scaling the backend microservices that power them - and, given theseniority of this role, you'll also help shape system design and infrastructure decisions as we scale.

You'll work alongside engineers, product managers, and AI agents as part of our AI‑first operating model, where lean, high‑autonomy teams ship fast and learn faster. This is a hands‑on engineering role for someone who's comfortable owning a feature end‑to‑end - from initial design through to production - and who wants to grow their craft in a fast‑moving, ambitious environment.

Where you'll focus

• Frontend development using modern JavaScript frameworks (React.js or Next.js)
• Backend development using Python‑based microservices
• System design and infrastructure, contributing to architectural decisions as we scale
• End‑to‑end feature ownership across the stack
• (Nice‑to‑have) Exposure to Data Science / Data Engineering workflows

Key Responsibilities

• Design, build, and maintain full stack features - from frontend UI/UX through to backend services andAPIs in Python.
• Contribute to system design and infrastructure decisions, helping evolve our technical foundations as wescale.
• Get involved across the full Software Development Lifecycle, from initial planning and design throughexecution, release, and monitoring in production.
• Write clean, well‑tested, maintainable code, and champion good engineering practices across the team.
• Collaborate closely with product managers, designers, and fellow engineers to translate requirementsinto working software.
• Build and consume APIs (REST/GraphQL) that connect frontend experiences to backend services.
• Work with AI agents as part of our AI‑first operating model, using clear specifications to shape high‑quality, AI‑assisted engineering work.
• Take ownership of the quality, performance, and reliability of the features you ship.
• Participate in code reviews, giving and receiving candid, constructive feedback.
• Stay curious about new tools and technologies, including opportunities to explore Data Science / DataEngineering problems as they arise.

What are we looking for?

We hire for how you think and how you ship. You should apply if you:

• Have around 5+ years of professional experience as a full stack / senior software engineer, with a balanced skill set across frontend, backend, and infrastructure.
• Have strong, hands‑on experience with front‑end technologies such as React.js or Next.js, and solidbackend experience building and maintaining Python‑based microservices.
• Are comfortable contributing to system design and infrastructure decisions, reflecting the seniority ofthis role.
• Are comfortable working across the full stack and can move fluidly between frontend, backend, andinfrastructure concerns.
• Have solid experience working in an agile environment and know how to embed quality into fast-movingteams.
• Bring exceptional attention to detail and a genuine ownership mindset over what you build.
• Are enthusiastic about new technologies, with the ability to adapt and learn quickly - we're open tocandidates with strong experience in other modern languages/frameworks if the core skill set andseniority are a strong match.
• Have an awareness of spec‑driven AI development and how clear specifications shape the quality of AI‑assisted engineering work.
• Have the confidence and initiative to evolve ideas and pull pieces of work together into meaningfulchange.
• Have an active interest in self‑learning and growing your craft.
• Nice‑to‑have: exposure to Data Science / Data Engineering (not core to the role, but a strong plus).

You don't have to tick every box. If you're a strong engineer who's hungry to step up, we'd still like to hear from you.

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

Above all, our people show a willingness to work together and get their hands dirty to deliver product success, which means our customers are successful!

What We Offer

• Competitive salary
• Be part of a leading global venture builder, Blenheim Chalcot, and learn from the incredible talent in BC.
• Be exposed to the right mix of challenges and learning and development opportunities
• Flexible Benefits including Private Medical Subsidiaries, Life Assurance, Pension scheme etc
• 25 days of paid holiday + your birthday off!
• Quarterly team socials