1 to 25 of 381 ECMAScript Jobs in London

continuous improvement. Your responsibilities Design, build and evolve scalable back-end services using C# and .NET Core, alongside developing front-end features with modern JavaScript frameworks to enhance user experience. Design and implement RESTful APIs, ensuring high standards of performance, reliability and security. Build, deploy and operate services ...

continuous improvement. Your responsibilities Design, build and evolve scalable back-end services using C# and .NET Core, alongside developing front-end features with modern JavaScript frameworks to enhance user experience. Design and implement RESTful APIs, ensuring high standards of performance, reliability and security. Build, deploy and operate services ...

Proficiency in writing and executing various types of tests including unit, system, performance, and integration tests. Proficiency in frontend technologies: HTML, CSS (Sass) and JavaScript (React.js) and experience in writing automated tests. Experience of working with a wide variety of stakeholders including product owners, delivery managers and architects. Experience ...

using TypeScript, leveraging frameworks such as Next.js or Vite. GenAI Frameworks: Familiarity with tools like LangChain, LangGraph, CrewAI, or Vercel AI (in Python or JavaScript). LLM experience: Practical experience with Large Language Models (LLMs) such as OpenAI, Anthropic, Mistral, or Llama, and tools like Ollama. Cloud Platforms: Proficiency ...

from the roadmap. Solve ambiguous problems with scalable solutions. Skills Knowledge and Expertise Essential: Strong expertise in Python web development frameworks (e.g., Django) and JavaScript/TypeScript, with experience working in cloud environments such as AWS, Azure, or GCP. Skilled in applying software technical design principles to build scalable, secure ...

React Hook Form + Zod) and data fetching with TanStack Query .Comfort with a modern build toolchain (Vite), HTML5, CSS (Flexbox/Grid), and JavaScript ES6+ .Authentication & Authorisatio nHands-on experience implementing JWT-based auth (access + refresh tokens) and OAuth2/OpenID Connect flows .Secure password handling (bcrypt/ ...

efforts, introducing new ideas and technologies What You'll Bring Proven experience as a Full Stack Engineer or similar role Expertise in Node, React, JavaScript/TypeScript, HTML, CSS, and responsive design principles Strong understanding of Back End technologies and best practices Passion for writing clean, well-tested code Experience ...

experience with: Infrastructure as Code (Terraform, Ansible or similar) CI/CD pipelines and DevOps tooling C# (.NET 8+) and/or Java (Spring) JavaScript using a modern framework (React, Angular or similar) Bash and PowerShell AWS, ideally including Amazon Connect Containerisation and orchestration (Docker, Kubernetes) Linux environments Nice ...

work directly with the CEO, strategists, and clients. Your decisions ship Qualifications Proficient in front-end development: HTML, CSS, and modern JavaScript frameworks (React preferred) Skilled in back-end development: server-side languages, database management, API design Proven full-stack delivery — end-to-end ownership from architecture to deployment Strong ...

development Git and version control Experience with relational and/or NoSQL databases Nice to have Exposure to Node.js and TypeScript Experience working with JavaScript-based frontends Azure DevOps or GitHub Actions Docker and Kubernetes Microservices architecture Messaging or event-driven systems Reasonable Adjustments: Respect and equality are core values ...

application development (.NET Core, C#) or winforms/WPF (C#) development. Our client will provide you with training into: .NET 10.0, WPF, MVVM, Prism, JavaScript, React, Angular 21, Microservices, MongoDB, Vue.js, TypeScript, Azure, AWS, ASP.NET Core Web API, Entity Framework, Node.js, Elasticsearch, Agile, TDD, BDD, Scrum, Kanban and Azure SQL. ...

such as Sitecore, Optimizely, Umbraco, Alterian, Immediacy, Ektron, Kentico, Sitefinity or dotnetnuke. Our client can provide you with industry recognised training in: .NET 10.0, JavaScript, React, Angular 21, Microservices, MongoDB, Vue.js, TypeScript, Azure, AWS, ASP.NET Core Web API, Entity Framework, Node.js, Elasticsearch, Agile, TDD, BDD, Scrum, Kanban and MongoDB. This ...

Azure/Google ecosystems helpful but not required Strong familiarity with general modern web and mobile application development, including hands‐on experience working with JavaScript (Typescript preferred) and Python stacks Cross functional team collaboration experience, especially working with engineers and user experience/product designers, as well as external stakeholders ...

have: 5+ years of experience building frontend applications Strong proficiency in React and Next.js Understanding of SSR, SSG, and modern rendering strategies Strong JavaScript/TypeScript, HTML, and CSS skills Experience with Azure cloud environments Experience with Azure DevOps Experience with scalable SaaS applications Experience with REST APIs Understanding ...

hear from you: Technical Skills Experience building cloud-hosted consumer applications usingopen sourcetechnologies such as Pythonor Node Knowledge of modern frontend development, including JavaScript/TypeScript with frameworks like React or Next.js, and experience building intuitive, user-focused interfaces Experience designing and implementing backend systems, ideally using Python for data ...

solutions; manage product backlog with Product Owner Write, review, and approve specifications; conduct code reviews Develop, test, and implement software using Java, C#, SQL, JavaScript Mentor team members on technical and financial domain expertise Coordinate cross-team integration and provide customer support Skills Required Technical: Java, C#, Python, API development ...

environment. Demonstrate strong experience working with Microsoft Dataverse, including data modelling, security roles, relationships, and solution configuration. Develop and customise solutions using C# and JavaScript, extending Dynamics 365 and Power Platform capabilities where required. Use HTML and CSS to support user interface customisation and styling. Work with Git code repositories ...

engineers through reviews and technical guidance Collaborate with product and operations to deliver practical solutions Improve system performance, reliability, and developer workflows Front-end JavaScript/TypeScript Vue/Nuxt or similar REST API integration Solid CSS/SCSS/SASS State management and component-based development Unit/ ...

ability to lead teams, influence stakeholders and deliver under pressure • Comfortable juggling multiple projects and “controlled chaos” at pace Skills • Requirements Analysis • .NET Framework • JavaScript • SQL • Software Development • Azure DevOps Services • ASP.NET • Azure AI Foundry • Continuous Integration and Continuous Delivery (CI/CD) • Artificial Intelligence (AI) • C# • Microsoft Azure • Team ...

desirable. Hands-on experience in Playwright, Selenium Grid & WebDriver C#, SQL, Ruby, Specflow, and Cucumber. Experience in using AI technologies such as Co-Pilot. Javascript experience. Good exposure to SOAP, REST based APIs. Good exposure to DevOps/Test Plan APIs. Structured and disciplined with good interpersonal skills. Ability ...

complex backlog, finding genuine satisfaction in driving platform‐wide improvements and untangling legacy code. Deep Backend Proficiency: Extensive proficiency in Node.js, TypeScript, and JavaScript, with strong understanding of APIs, Webhooks, and OAuth protocols. Strong Cloud & Infrastructure Knowledge: Proficient experience with AWS (Lambda, SQS, DynamoDB, ECS, SNS, CloudFormation), containerization, data ...

typically candidates at this level have 5+ years of software engineering experience. You should be prepared to undertake our pair-programming interview stage in Javascript or Typescript, and you’ll be assessed as if this has been your primary language. This is a full-stack role — if you are only ...

collaborative environment and are eager to make an impact, we want to hear from you! Technical Skills Front-end: Strong proficiency in React.js, JavaScript/TypeScript, Redux/RTK, and modern UI patterns, develop framework is essential - More to React JS and Java script Back-end: Expertise in C# .NET … RESTful APIs with a focus on scalability and resilience. Create UI Components: Craft responsive and modular UI components using React JS and modern JavaScript/TypeScript patterns. Collaboration: Work closely with business stakeholders and domain experts in Risk, Regulatory Reporting, and Finance. Power BI Expertise: utilise your knowledge of Power ...

Stack Developer within the Public Sector. Active SC and NPPV3 Clearance. Senior-level expertise in either Java/Spring (Boot, Data JPA, Security) or JavaScript/TypeScript with React; mid-level experience acceptable in the other Proven experience delivering high-quality, cross-functional solutions using microservices and micro-frontend architectures ...

account or portfolio level Experience integrating with catastrophe modelling tools or APIs (e.g. AIR Touchstone, RMS, Analyse Re) Strong full-stack development experience (Angular, JavaScript/jQuery, Python or C#) [ Solid knowledge of SQL Server and T-SQL, with strong debugging and optimisation skills Desirable Experience with cloud platforms ...