What Jobs are available for Senior Developer in London?

Full Stack Developer - (Strong Frontend Developer)

Salary: Negotiable to £50K Dependent on Experience

Location: Central London – Hybrid working 1 day a week in the office

Ref: J12935

A marketing effectiveness consultancy geared toward the measurement of every element of the marketing mix: from in-store and field sales activity to the more traditional measurement areas of ATL and digital marketing activity. Founded in late 2014, their story has been one of rapid growth with the latest year already looking set to deliver double the turnover of the previous and a strong international client base.

With this success they seek to expand their engineering team with a proactive and skilled Full Stack Developer with proven frontend development skills to contribute to the design, development, and deployment of internal and client-facing applications. The role requires collaboration across technical and product teams, working closely with data scientists and business analysts to deliver robust solutions. The Full Stack Developer will have experience of building web applications, an interest in data analytics, and a desire to contribute to high-impact projects.

Key Responsibilities:

• Develop and maintain scalable backend services using Python frameworks (Flask/Django)
• Build responsive and user-friendly frontend interfaces with React or other modern frameworks
• Design and optimize database structures and queries in PostgreSQL
• Ensure the efficient and secure handling of large datasets for analytics purposes
• Collaborate with data scientists to integrate complex statistical models into production applications
• Participate in agile development cycles, ensuring continuous delivery of high-quality features
• Manage cloud-based infrastructure using Azure, ensuring optimal performance and scalability
• Write unit tests and ensure software quality through automated testing frameworks
• Support the deployment and monitoring of applications in production environments
• Contribute to system architecture decisions and process improvements
• Data Visualization: Experience with libraries such as matplotlib, seaborn, plotly
• Cloud Infrastructure: Familiarity with Azure and cloud-based deployments
• Version Control: Proficient with GitHub
• Message Queuing: RabbitMQ or similar
• Data Processing: Experience working with data pipelines and processing large datasets

Full current and future UK working rights required; sponsorship not available.

This opportunity would be great for someone looking to move to their 2nd job where they can continue to develop their frontend development skills and be involved in some backend development work.

Associate

Full-time

Design and Information Technology

Technology, Information and Media

At Theodo, we help businesses create innovative digital solutions. Specialising in web and mobile apps, we bring deep expertise in cloud-native technology and agile delivery. As part of Theodo Group, we collaborate with a network of 10 companies globally, focusing on varied sectors!

What you’ll be doing:

As a Full Stack Developer, you’ll create innovative web and mobile applications, working in a small, dynamic team to build scalable solutions with cutting-edge technologies. You’ll engage directly with clients, including CEOs and co-founders, to understand their needs and deliver bespoke solutions. You’ll learn hands-on, supported by experienced developers, and gradually take on more responsibility, including mentoring junior developers and managing your own projects. You'll thrive on solving complex problems and expanding your technical expertise.

What we’re looking for:

- 2+ years of development experience

- Experience with TypeScript

- Proficiency in React (with Next.js ) or React Native (with Expo)

- Understanding of Node.js (preferably with NestJS or AWS Lambda)

- Strong written and verbal communication skills

Beneficial Skills & Experience:

- Exposure to AWS environments

- Knowledge of other OOP languages (Java, C#, Python, Go)

- Experience in a client-facing role

Why Join Us?

- Work in a dynamic, collaborative global team.

- Opportunities for career growth and development.

- Competitive salary and benefits such as private healthcare, tech equipment budget, monthly socials & more!

Please apply now for consideration!

The Role We're looking for a Full Stack Engineer to join the Ffern team. They'll report directly to the CTO.

We are open to either backend or full-stack developers, but please note a large amount of the role will be systems design and architecture. Technologies: Node.js, PostgreSQL (supabase). Experience with Next.js and the Shopify APIs would be a massive boon.

Key Responsibilities

• Systems Architecture: Build efficient, scalable, well-thought-out systems and processes.
• Internal Tools: Construct internal dashboards and tools to help us understand how our systems are operating.
• Database Management: Help set up and manage Ffern's databases.
• Performance: Improve performance on Ffern's systems and website.
• Be a Hero: Save the day by flagging and responding to systems related technical emergencies.

Your Profile

• Experience: 2–4 years experience as a full stack developer.
• Education: Academic degree from a top-tier university.
• Technically Minded: You reason logically. You get a kick out of architecting systems and building processes.
• Enthusiasm: Passionate about working in the start-up world for a sustainable and mission-driven brand.

What We Offer

• Competitive salary: Experience dependent.
• Healthcare: Private healthcare offered as standard.
• Holidays: 25 days holiday + bank holidays, growing by 1 day per year spent with us.
• Remote work: All full-time London studio roles are three days a week in the studio, with two days flexible (team lunch at a top Hackney eatery if you come in on the flexible days).
• Ffern membership : All of our team are members of the Ffern ledger.
• Team dynamic: Fun, laid-back and sociable team with regular team meals, breakfasts, drinks and outings.
• Beautiful work environment: We work from a pair of sunlit studio spaces off Columbia road with state-of-the-art kit, MacBooks and breakout spaces.

N.B. Ffern is growing fast, with a plethora of exciting projects on the horizon. This means our roles are somewhat flexible. If you don’t tick every box, but feel passionate about what you could bring to the table, please do apply.

Join to apply for the Full‑Stack Developer role at Stelia

Overview

• Build user‑facing experiences and APIs for orchestrated data and compute workflows.
• Work across FastAPI backends, data stores, caches, and a modern web UI.

• Design and implement FastAPI services and integrations with Prefect flows.
• Build UI features for monitoring runs, scheduling, and results; implement real‑time status/caching with Redis where appropriate.
• Model and optimize schemas and queries in MySQL/PostgreSQL; write safe, well‑tested migrations.
• Create robust CI/CD pipelines with GitLab; own code quality, tests, and release automation.
• Implement security best practices across authN/Z, rate limiting, input validation, and secrets handling.
• Collaborate on API design (REST, potentially gRPC) and internal SDKs for Python/Go/Rust services.
• Add observability (structured logs, metrics, traces) to diagnose performance and reliability issues.

• 3+ years building production web applications.
• Strong Python and FastAPI experience (async patterns, dependency injection, pydantic).
• Solid SQL fundamentals and data modeling; practical experience with Redis for caching/queues/rate‑limits.
• Comfortable with Kubernetes basics, containerized development, and GitLab CI/CD.
• Experience building modern SPA frontends with TypeScript and a contemporary framework.
• Familiarity with Prefect concepts (flows, tasks, deployments, storage, results).

• Performance work on high‑concurrency APIs; profiling and async optimization.
• Exposure to Go or Rust for high‑performance components.
• Background jobs, scheduling, and event‑driven patterns.

Stelia is building a global distributed intelligence platform empowering enterprises to integrate and scale AI’s limitless potential. By optimising data mobility and connecting diverse AI resources, Stelia simplifies distributed AI operations, making them accessible anywhere. Committed to innovation, collaboration, and simplicity, we enable enterprises to lead the AI revolution and drive transformative change across all sectors.

Referrals increase your chances of interviewing at Stelia.

Overview

Department: Digital Transformation

Location: City, London

Compensation: £50,000 - £60,000 / year

Role: Full-Stack Developer at Moore Kingston Smith

We are seeking a skilled Developer to join the Digital Transformation team to contribute to the development of innovative products that aim to revolutionise the way auditors and accountants work. This role involves accelerating the creation of our core product suite, helping to automate repetitive tasks and enable accountants to focus on data-driven insights and analytics. This position provides an opportunity to work in a small, autonomous team, with mentorship from experienced developers and data scientists to further develop your expertise. It offers a chance for career progression as the role evolves over time.

The Digital Transformation team is at an exciting growth stage, driving ambitious initiatives across the firm. Moore Kingston Smith is a leading professional services organisation offering audit, advisory, and other services. The team operates with a professional yet relaxed culture, fostering collaboration and innovation. Team members enjoy access to professional development through paid courses, on-the-job mentoring, and opportunities to attend relevant meetups and industry events.

• Collaborate with a small team of developers, contributing to daily code reviews and merge requests.
• Develop across the entire product stack, including frontend interface, backend API layer, and analytics/data processing engine.
• Lead projects independently, from requirements gathering through to deployment.
• Mentor junior developers to support their technical growth.
• Solve complex challenges related to data and presentation in accountancy.

• At least 3 years of experience as a full-stack developer, delivering robust production-ready solutions.
• Proficiency in the following technologies:
• Backend: Python, Django
• Frontend: JavaScript, React, Next.js
• Version control: Git
• Comfortable working with Python and JavaScript professionally, with experience in Django and React.
• Ability to build data-intensive applications and manage complex backend logic, including external API integrations.
• Experience in creating responsive user interfaces that function across browsers and mobile devices.
• Capable of working independently and taking ownership of technical projects.
• Strong analytical skills and problem-solving abilities.
• Effective time management and prioritisation skills under tight deadlines.

• Experience deploying and managing applications using Azure and Docker.
• Familiarity with frameworks such as LangChain and expertise in Retrieval-Augmented Generation (RAG) models for AI-driven applications.
• Proficiency with pandas for data manipulation.

• Salary Reviews: Regular salary reviews to recognise your contributions and performance.
• Generous Annual Leave: Enjoy 25 days plus three days off at Christmas.
• Flexible Working: We're committed to a positive work-life balance, offering a hybrid working policy that prioritises your well-being and flexibility.
• Comprehensive Wellbeing Support : Healthcare Cash Plan, Access to Digicare+, Employee Assistance Programme, and more!
• Professional Subscriptions: Invest in your growth and development.
• Inclusive Employer: Be part of a diverse team with equity, inclusion, and flexibility at the core

About Sentra

Sentra is building the AI backbone for post-acute care, revolutionizing how healthcare providers manage administrative workflows. Right now, post-acute providers are drowning in administrative complexity—so much of their work depends on manually processing vast amounts of unstructured clinical and financial data. These manual, error-prone workflows add friction, increase costs, and place immense financial pressure on an already fragile industry.

Our mission is to abstract away these burdensome processes, enabling providers to focus on what matters most: delivering high-quality patient care. Our broader vision is to connect the entire continuum of care—hospitals, post-acute providers, payers, and community-based services—through intelligent automation.

As we scale, we’re looking for exceptional engineers to join our mission-driven team and play a pivotal role in shaping the future of healthcare AI.

We are looking for a Full Stack Developer to take ownership of end-to-end product development. As one of the first engineering hires, you’ll work closely with the founding team, own technical decisions, and build highly scalable and secure systems that directly impact patient care and operational efficiency.

This role is ideal for someone who thrives in an early-stage, high-ownership environment, enjoys solving complex technical problems, and is excited about building AI-powered solutions for healthcare.

• Architect and implement features across the entire stack.
• Design, build, and maintain AI-driven workflows that automate clinical and administrative tasks for post-acute providers.
• Integrate AI models into production, staying ahead of advancements in LLMs to enhance platform intelligence.
• Ensure high reliability, security, and scalability, integrating best practices in modular system design, testing, and observability.
• Work closely with our customers to iterate and refine the platform based on feedback.
• Embrace a founder’s mindset, proactively driving projects from conception to deployment and contributing to the company’s strategic growth.

• 2+ years of experience in full-stack development with proficiency in modern web frameworks and cloud architectures (Vue.js, Python, C#, SQL Server, Azure, or similar).
• Degree in Computer Science, Engineering, Mathematics, or a related technical field (or equivalent experience).
• Proven track record of building and maintaining scalable web applications in fast-paced environments.
• Strong problem-solving skills, ownership mindset, and ability to thrive in high-autonomy environments.

• Experience working with LLMs in production.
• Prior experience in startups or greenfield projects.

• Competitive compensation: Top-of-market salary + equity package.
• Learning & development budget to support continuous growth.
• Collaborative and mission-driven team working on high-impact AI solutions for healthcare.
• Regular team-building events and opportunities to shape company culture.

1. Application Review: Email your resume to
2. Initial Screen (30 min): Chat with a founder about your background, motivations, and learn more about Sentra.
3. Technical Interview (1h30): An exploration of your engineering skills and past work, highlighting how you approach challenges, make technical decisions, and balance trade-offs.
4. Culture Interview (30 min): Meet other team members and ensure alignment with our values.
5. Offer.

• Build and maintain robust mobile apps using React Native and Expo
• Optimise app performance, implement modern architecture patterns, and handle push notifications, offline-first features, and state management
• Collaborate on backend APIs (REST or GraphQL) and integrate secure authentication methods - JWT, OAuth
• Deploy and manage cloud infrastructure and services on AWS, including Lambda, DynamoDB, S3, AppSync
• Support CI/CD pipelines and ensure high-quality, monitored deployments

• 5+ years of professional software development experience
• 3+ years hands-on React Native and Expo experience
• Strong understanding of the mobile development lifecycle and app deployment processes
• Experience with database design (SQL or NoSQL) and backend integrations
• Proven AWS deployment experience and familiarity with Infrastructure as Code (CDK)
• Knowledge of monitoring, logging, and application performance optimisation

• Outside IR35, long-term contract with genuine extension potential
• High-value project
• Opportunity to influence software adoption at global scale
• Flexibility to work remotely within UK hours

We’re looking for a talented and motivated Full Stack Developer to join our team and build secure, high-quality software. You’ll work in small Scrum teams alongside Product Owners, testers, and support staff to deliver scalable, cost-effective solutions. Responsibilities include designing, developing, testing, and documenting applications that meet business needs, with a focus on performance, reliability, and collaboration.

Joining us means being part of a forward-thinking organisation at the forefront of the logistics industry. You will have the chance to network with key players, develop your expertise, and influence one of the most critical sectors in the UK.

Logistics UK, formerly the Freight Transport Association is one of the biggest business groups in the UK, representing the entire industry with members from the road, rail, sea, and air industries, as well as the buyers of freight services such as retailers and manufacturers whose businesses depend on the efficient movement of goods.

An effective supply chain is vital to Keep Britain Trading, directly impacting over 7 million people employed in making, selling and moving the goods that affect everyone everywhere. With Brexit, technology and other disruptive forces driving changes in the way goods move across borders and through the supply chain, logistics has never been more important to UK PLC.

• Work within project teams to develop and enhance the company’s bespoke systems.
• Design, code, test, and maintain custom applications in line with business requirements.
• Estimate development efforts and assist in analysing and resolving defects and issues.
• Collaborate as part of a small SCRUM team and actively participate in Scrum ceremonies.
• Provide third-line support for in-house applications and contribute to out-of-hours releases.
• Participate in code reviews and ensure development aligns with company policies and security guidelines.
• Use Azure DevOps to manage bugs, user stories, tasks, and automate builds and releases.
• Manage source control using Git within Azure DevOps, following structured branching strategies.

Requirements

• Software Development Expertise : Skilled in designing, coding, testing, and maintaining moderately complex systems with a strong passion for creating enterprise-level solutions.

• Technology Stack Proficiency : Experienced in Microsoft technologies (C#, ASP.NET Core, Web API), JavaScript (AngularJS or React), and Azure Microservices.
• Development Tools & Practices : Proficient with Visual Studio IDE, Git for source control, and familiar with version control and branching strategies (preferably Git/Azure DevOps).
• Testing & Quality Assurance : Familiar with SQL, NUnit for unit testing, and committed to improving code quality through collaboration, e-learning, and industry seminars.
• DevOps & Automation : Familiar with Azure DevOps pipelines, automated builds/releases, and secure application development practices including OWASP top 10.
• Agile Methodologies : Knowledgeable in Agile/Lean development frameworks such as Scrum and Kanban.
• Soft Skills & Teamwork : Strong troubleshooting and time management skills, effective communicator, and thrives in team environments under pressure.
• Education & Industry Awareness : Bachelor’s degree in computer science or related field preferred; understands the dynamics of working within a trade association.

Benefits

We value our employees and offer a wide range of benefits recognising that no two employees are the same – everyone has different preferences and needs that change over time.

• 25 days of annual leave plus bank holidays
• Christmas Working Arrangement for extra days off during the festive period
• Health Cash Plan for all employees and Private Medical Insurance for managers
• Employee Assistance Programme and Mental Health First Aiders
• Enhanced Family Leave policy
• Flexible and remote working arrangements
• Two paid days off per year for charity or volunteering work
• Various learning and development opportunities
• Range of pension schemes
• Award scheme to recognise outstanding employees
• Life Assurance Scheme for peace of mind

Rayo, part of the UBDS group, is seeking a Full-Stack Developer to contribute to the development and support of cloud-native applications deployed on Amazon Web Services (AWS). The successful candidate will work across the full software development lifecycle, combining solid Java/Spring Boot back-end development with modern front-end skills using frameworks such as React or Angular. The role offers opportunities to support, design, and build scalable and secure solutions for high-impact public sector programmes.

This position is suitable for candidates with foundational experience in full-stack development, as well as those with deeper technical capability looking to further progress within an Agile delivery environment.

Key Responsibilities:

• Design, develop, and maintain scalable full-stack solutions hosted on AWS.
• Build and integrate RESTful APIs using Java and Spring Boot.
• Develop responsive user interfaces using modern JavaScript frameworks (React or Angular).
• Participate in Agile ceremonies and contribute to sprint planning and reviews.
• Support CI/CD processes and assist in automated testing and deployment.
• Collaborate with DevOps, QA, and platform teams to ensure high-quality delivery.
• Conduct and participate in code reviews to maintain technical standards.
• Troubleshoot and resolve application issues across the stack.

Requirements

• Proficient in Java and Spring Boot for back-end development.
• Experience with front-end development using React or Angular.
• Familiarity with AWS services including Lambda, RDS, and DynamoDB.
• Understanding of CI/CD pipelines, automated testing, and deployment practices.
• Experience building and consuming APIs in a microservices architecture.
• Knowledge of version control using Git and exposure to code review processes.
• Demonstrated ability to work within Agile delivery teams.

Desirable Experience:

• 1–4 years of full-stack development experience.
• Hands-on involvement in AWS cloud environments and delivery pipelines.
• Previous experience on public sector or regulated projects is advantageous.
• AWS certification (e.g., AWS Certified Developer – Associate) is a plus.

Benefits

Why people choose to grow their careers at UBDS Group

Professionals choose to grow their careers at UBDS Group for its reputation as a dynamic and forward-thinking organisation that is deeply committed to both innovation and employee development. At UBDS Group, employees are given unique opportunities to work on cutting-edge projects across a diverse range of industries, exposing them to new challenges and learning opportunities that are pivotal for professional growth. The Group’s culture emphasises continuous improvement, offering ample training programs, mentorship, and the chance to gain certifications that enhance their skills and marketability.

UBDS Group fosters a collaborative environment where creativity and innovation are encouraged, allowing employees to contribute ideas and solutions that have a tangible impact on the company and its clients. This combination of professional development, a culture of innovation, and the opportunity to make meaningful contributions makes UBDS Group an attractive place for those looking to advance their careers and be at the forefront of technological and operational excellence.

Employee Benefits

• Training – All team members are offered a number of options in terms of personal development, whether it is technical led, business acumen or methodologies. We want you to grow with us and to help us achieve more
• Private medical cover for you and your spouse/partner, offered via Vitality
• Discretionary bonus based on a blend of personal and company performance
• Holiday – You will receive 25 Days holiday, plus 1 day for Birthday and 1 day for your work anniversary in addition to UK bank holidays
• Electric Vehicle leasing with salary sacrifice
• Contributed Pension Scheme
• Death in service cover

About UBDS Group

At UBDS Group our mission is to support entrepreneurs who are setting new standards with technology solutions across cloud services, cybersecurity, data and AI, ensuring that every investment advances our commitment to innovation, making a difference, and creating impactful solutions for organisations and society.

Equal Opportunities

We are an equal opportunities employer and do not discriminate on the grounds of gender, sexual orientation, marital or civil partner status, pregnancy or maternity, gender reassignment, race, colour, nationality, ethnic or national origin, religion or belief, disability or age.