Senior Web Application Developer jobs in Chelmsford

About Pronetx Pronetx is a cutting-edge consulting firm that specializes in transformative customer experience (CX) solutions powered by AWS. With decades of experience deploying sophisticated CX solutions for industry leaders like Capital One, Social Security Administration, and Hilton, we're known for pushing the boundaries of what's possible in customer experience technology. Job...

Job Description Senior JavaScript Developer / front End Engineer (Vue 3) Billericay / WFH to £75k Are you a JavaScript web technologist seeking an opportunity to work with a modern tech stack on Greenfield projects? You could be progressing your career in a senior, hands-on role at an eCommerce payments solutions provider that has experienced great success in the last year and is growing as a...

You will be working in a fast-paced environment to develop new website themes and add new features in a complex Next. js-based codebase (including a CMS). This is a great opportunity for the right person to take on a challenging and broad role. Homeflow is operating on a fully remote basis but occasional travel will be required for our company meet ups (bi-annually at most in the UK).

🚀 About Webigence and Spark Travel Webigence has 25 years of experience crafting UX‑first, often highly complex software. Our engineers pair forward‑thinking agile practices with an obsession for intuitive design, shipping products that feel effortless even when the logic underneath is anything but. Alongside a handful of long‑standing third‑party clients, we’re scaling our own SaaS...

You will work closely with developers on Next.

Department: Support Reports To: Application Software Support Manager Location: Remote Salary: £55k - £60k /yr (depending on experience) Contract Type: Permanent – Full Time Role Summary We're looking for an experienced full-stack .NET developer to join our team in a new and exciting role. This role will initially be supporting an array of clients, helping our support team to continue to...

Our client is a fast-growing SaaS company building web and mobile products used worldwide for organising, engagement, and field operations. They’re small, sharp, and engineering-led — shipping fast, solving real problems, and working in a genuinely collaborative environment. They’re now adding a fourth A-player Full-Stack Developer to their tight 3-person engineering team. If you want real...

BRAND NEW ROLE - Senior Exec Level - Marine Geo Director of Business Development - Geotechnical Engineering & Geoscience Consulting About the Company Our client are a growing offshore geotechnical services and consulting unit, focused on delivering high-quality, technically robust solutions across the offshore, nearshore, and onshore environments. While offshore geotechnical investigations...

Senior Applications Developer Contract: March 2026 Working Hours: Full-Time Salary: £384.14 PAYE / £500.00 Umbrella, daily rate Closing Date: Monday 1st December 2025 About the role Essex County Council is ambitious and by 2030 it will be one of the most forward looking, effective and financially sustainable Councils in the country. ECC will be a leading-edge digital council that drives...

You will be a hands-on player-coach, owning outreach and qualification while also helping to design the BDR/SDR process, playbooks and best practices.

You will use modern tools (HubSpot, Clay, Instantly, Lemlist, etc.) and AI to build signal-based, multi-channel plays that generate qualified meetings and pipeline across both partners and direct prospects.

About Roadern Roadern is building an AI-powered road and asset intelligence platform used by road authorities and councils. Our product is mobile-first, turning smartphone imagery, GPS, and sensor data into actionable insights at scale. We’re looking for a senior engineer who is strong in React Native, comfortable with map-heavy interfaces, and happy working across mobile and web in a startup...

Job Description Position: Front End JavaScript Developer Reports to: Front End Development Team Lead Hours: 40 hours Location: 3 days in North London office (Monday – Wednesday) Salary: £60 - £80,000 + eligibility for performance bonus Start date: ASAP Purpose of the role: As a Front End Developer you will join one of our multinational Scrum teams to create state-of-the-art software...

You will design, develop, and maintain our platform’s backend infrastructure, focusing on multi-tenant architectures, security, and efficient LLM integration. This role requires a strong understanding of Python web frameworks, cloud services (particularly AWS), and modern AI approaches including working with agentic architecture.

You will be responsible for the entirety of the back end features of the products.

You will be in charge of building scalable backend services and awesome messaging queues.

You will be responsible for developing a Python-based back end platform that's handling 100,000+s of interactions daily.

Reports to: Technology Director / Executive Sponsor Location: Remote with occasional travel to London (2 times a month) Contract: Full-time, permanent Base Salary: £70,000 – £80,000 location and experience dependent + 10% company bonus scheme and sales commission scheme Why This Role Exists Serve Legal is entering a new chapter: evolving beyond compliance auditing into AI enabled,...

Job Description Software Development Engineer III Expedia Group brands power global travel for everyone, everywhere. We design cutting-edge tech to make travel smoother and more memorable, and we create groundbreaking solutions for our partners. Our diverse, vibrant, and welcoming community is essential in driving our success. Why Join Us? To shape the future of travel, people must come...

You will be responsible for designing, developing and implementing solutions using the MS Integration Services & MS Power Platform suite including but not limited to Logic Apps, Service Bus, Event Grid, APIM, Functions & Function Apps, SQL Server, Azure SQL, Dataverse, D365 modules, 3rd-party APIs, Azure Synapse, Fabric and Key Vault.

You must speak, write and be able to understand fluent English. - Deep knowledge and regular usage of Firebase suite, especially Firestore. - Strong proficiency in TypeScript and modern JavaScript (ES6+).

You must enjoy constantly learning and researching to improve your level of expertise.

React / Next.js Developer – Contract (Outside IR35) 📍 Location: Remote (UK-based preferred) 📅 Contract Length: 2 months 💼 Contract Type: Outside IR35 💰 Rate: £300 per day 🚀 Start: ASAP Overview We’re looking for an experienced React / Next.js Developer to join us on a short-term contract to help deliver and enhance a modern, high-performance web application. You’ll be working closely with...

You will be responsible for the entirety of the back end features of the products.

You will be in charge of building scalable backend services and awesome messaging queues.

You will be responsible for developing a Python-based back end platform that's handling 100,000+s of interactions daily.