Overview

Expleo is seeking an experienced Senior MERN Developer to join our high‑performance engineering team. You will play a key role in designing, developing, and delivering modern, scalable, high‑quality applications using the MERN stack (MongoDB, Express, React, Node.js). This is an opportunity to work in a client‑facing, innovation‑driven environment where you’ll influence architectural decisions, mentor developers, and help shape digital transformation solutions across multiple sectors.

Responsibilities

Architect, design, and implement high‑performance applications using the full MERN stack.
Lead technical discussions and collaborate with cross‑functional teams including UX/UI, DevOps, QA, and Business Analysis.
Develop clean, reusable, well‑documented code following best practices and Expleo quality standards.
Own technical delivery across project phases including estimation, planning, development, testing, and deployment.
Optimise application performance, security, and scalability across front‑end and back‑end components.
Drive continuous improvement by recommending new tools, technologies, and approaches.
Participate in code reviews, pair programming, and mentoring junior developers.
Work closely with clients to gather technical requirements and propose effective solutions.
Troubleshoot complex issues and provide strong root‑cause analysis and long‑term fixes.

Qualifications

Bachelor’s degree in Computer Science, Software Engineering, or equivalent experience.
Strong foundation in web application development, system design, and modern JavaScript frameworks.
Deep expertise in the MERN stack: MongoDB, Express.js, React, Node.js.
Familiarity with cloud platforms (AWS, Azure, GCP) is desirable.

Essential skills

Client-facing skills
People management skills - introducing and building ways in which people can learn from each other, encouraging mentoring and the transfer of knowledge by designing and delivering learning interventions
Team work and emotional intelligence
Good self-management – continuous performance is both an objective and a mind-set
Has an innovative approach – a bold thinker and doer, matching creativity with vigilance
High value on openness and transparency

Experience

5+ years of professional development experience, including several years in MERN‑focused roles.
Proven experience delivering complex, scalable web applications in an agile environment.
Experience working with distributed systems, asynchronous patterns, and API integrations.
Background in mentoring developers, leading technical tracks, or owning project modules.
Exposure to enterprise‑level digital transformation, large‑scale refactoring, or cloud migration projects is a strong advantage.

Benefits

At Expleo, we are committed to providing a competitive salary and substantial benefits offering with unique wellbeing, financial and employee recognition programmes.

We pride ourselves on our diverse and inclusive culture and offer a variety of family friendly policies and enhanced leave to help you achieve a healthy work life balance.

By providing significant learning and development opportunities, we encourage individual growth and success throughout your career with us.

Collaborative working environment – we stand shoulder to shoulder with our clients and our peers through good times and challenges
We empower all passionate technology loving professionals by allowing them to expand their skills and take part in inspiring projects
Expleo Academy - enables you to acquire and develop the right skills by delivering a suite of accredited training courses
Competitive company benefits such as medical and dental insurance, pension, life assurance, employee wellbeing programme, sports and social events, birthday hampers and much more!
Always working as one team, our people are not afraid to think big and question the status quo.

“We are an equal opportunities employer and welcome applications from all suitably qualified persons regardless of their race, sex, disability, religion/belief, sexual orientation or age”.

At Expleo, we understand that many people experience impostor syndrome throughout their lifetime, please do not let this discourage you from applying for this role. Our Talent Acquisition Team welcomes all CV’s and will consider your application in line with the values, requirements and role competencies.

Senior MERN Developer

Benefits

Job Description