Senior Software Engineer - Fullstack

Blenheim Chalcot; Mumbai City; On-site; INR 1,800,000 - 3,000,000; Full time

Benefits offered by this job

Private medical insurance

Life insurance

Pension scheme

25 days paid holiday + birthday off

Quarterly team socials

Job summary

Blenheim Chalcot is seeking a Senior Software Engineer (Fullstack) in Mumbai to build scalable, AI-enabled automation and real-time analytics products. You will own full-stack features across frontend and backend, work with React.js/Next.js and Python-based microservices, and contribute to architecture and infrastructure decisions in a fast-growing venture builder environment.

The role requires strong full-stack expertise, agile collaboration, and a drive to ship high-quality software in a

Qualifications

• Have around 5+ years of professional experience as a full stack / senior software engineer.
• Strong hands-on experience with front-end technologies such as React.js or Next.js and Python-based microservices.
• Comfortable contributing to system design and infrastructure decisions reflecting seniority.
• Able to work across the full stack and move between frontend, backend and infrastructure.
• Experience in agile environments with a focus on quality in fast-moving teams.
• Attention to detail and a strong ownership mindset.

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 and design to production release and monitoring.
• Write clean, well-tested, maintainable code, and champion engineering practices across the team.
• Collaborate with product managers, designers, and fellow engineers to translate requirements into working software.
• Build and consume APIs (REST/GraphQL) that connect frontend experiences to backend services.

Skills

React.js / Next.js

Python

Full stack

System design

Tools

REST/GraphQL APIs

Frontend frameworks

Job description

Title : Senior Software Engineer (Fullstack)

Location : Mumbai, India

• 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 BlenheimChalcot

Blenheim Chalcot India is part of Blenheim Chalcot, a global venture builder headquartered in London. With over 26 years of innovation, we’ve been at the forefront of creating some of the most groundbreaking GenAI-enabled companies. Our ventures lead the charge in digital disruption across a spectrum of industries, from FinTech to EdTech, GovTech to Media, and beyond. Our global presence spans the US, Europe, and Southeast Asia, with a portfolio that employs over 3,000 individuals, manages assets exceeding £1.8 billion, and boasts total portfolio sales of over £500 million.

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.

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 someonewho’s comfortable owning a feature end‑to‑end - from initial design through to production - and who wants togrow 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.

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

What are we looking for?

• 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 to candidates with strong experience in other modern languages/frameworks if the core skill set and seniority 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

• 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

Blenheim Chalcot is a proud Equal Opportunity Employer. Diversity is one of our core values, thus making it core to our business. We strive to maximize the diversity of our workforce and welcome applications from everyone. We encourage diversity through perspective, background, identity, and thought whilst also fostering an environment where everyone can express themselves regardless of your race, religion, sex, gender, colour, national origin, disability, or any other applicable legally protected characteristic. We are committed to continuing to nurture an inclusive environment and building a diverse workforce.