1 to 25 of 27 WebSockets Jobs in the City of London

capabilities. Experience with AI/ML integrations or recommendation systems. Expertise in Matrix/Synapse integration for real-time messaging and communication. Knowledge of WebSockets, real-time messaging, and event-driven architectures. Background in platform monetisation and payment integration. Strong familiarity with access control, authentication (OAuth, JWT), and data privacy More ❯

refinement, and retrospectives Evaluate and improve the frontend architecture, including state management and API integrations Help implement real-time frontend/backend communication using WebSockets Extend and optimise the use of Nx for a frontend monorepo setup Leverage Zustand and TanStack Query for state/data handling, and React Router More ❯

refinement, and retrospectives Evaluate and improve the frontend architecture, including state management and API integrations Help implement real-time frontend/backend communication using WebSockets Extend and optimise the use of Nx for a frontend monorepo setup Leverage Zustand and TanStack Query for state/data handling, and React Router More ❯

SQL/NoSQL) Bonus Points For: Familiarity with AI/LLM tools (LangChain, Vercel AI SDK, OpenAI APIs) Experience building real-time apps (e.g., WebSockets) Understanding of authentication/authorization flows in web apps Knowledge of financial services, fintech, or enterprise-grade products This is a rare opportunity for a More ❯

Tech Lead, SwiftUI | HealthTech, AI, Greenfield Start-up | Shoreditch, Hybrid | Up to £110,000 + Stocks & Benefits APIs & Communication: Strong understanding of REST, GraphQL, WebSockets, and API design best practices Ideally Fullstack TypeScript Engineer (across frontend and backend) Proven experience as a senior software engineer or tech lead, ideally in More ❯

Tech Lead, SwiftUI | HealthTech, AI, Greenfield Start-up | Shoreditch, Hybrid | Up to £110,000 + Stocks & Benefits APIs & Communication: Strong understanding of REST, GraphQL, WebSockets, and API design best practices Ideally Fullstack TypeScript Engineer (across frontend and backend) Proven experience as a senior software engineer or tech lead, ideally in More ❯

using Angular. Solid Solution Deisgn Experience. Nice-to-Have : Experience with Event-Driven Architecture using AWS services (SNS, SQS, EventBridge). Knowledge of GraphQL, WebSockets, or real-time data streaming. Exposure to DevOps and observability practices (e.g., Prometheus, Datadog, AWS CloudWatch, OpenTelemetry). Prior experience in leading distributed engineering teams. More ❯

React) Worked with a variety of storage technologies (eg. Postgres, Mongo, Redis, Object) Experience with async and bi-directional communication protocols and patterns (eg. WebSockets, SSE) Designed and implemented event-driven distributed systems (eg. Kafka/Pulsar, RabbitMQ, MQTT, or similar) Experience with container orchestration and service containerisation (Kubernetes, Docker More ❯

in TypeScript or JavaScript and Python. You have experience building high-performance, responsive web applications, and a deep understanding of HTTP protocols, REST APIs, WebSockets, and the DOM. You are comfortable operating across the stack, with strong knowledge of relational databases, web security best practices, and authentication. You have experience More ❯

MySQL, etc.) OpenSearch DynamoDB S3 Event-driven architectures Third-party API integration Access control and user permissions Implementing APIs used by single-page applications WebSockets Infrastructure as code (AWS CDK, Terraform, etc.) Docker AWS IoT What we’re looking for Circa 2 years of commercial or equivalent experience in a More ❯

following experience: 10+ commercial experience as a Frontend Developer Architecting and developing desktop and mobile interfaces React, React Native, Redux, React Hooks CSS, Typescript, Websockets, REST APIs Leading cross-functional teams to drive product launches and realise end-to-end solutions Bonus points : understanding of trading interfaces, financial experience, blockchain More ❯

and accuracy. Core Tech Stack Languages: Python (Python 3.10+), JavaScript and TypeScript for frontend Tools: RabbitMQ and ZeroMQ for messaging; PostgreSQL for data storage; Websockets for frontend communication Environment: Linux servers Observability: Prometheus, Grafana, Zabbix Benefits: Working alongside other extremely talented and driven engineers Extremely lucrative salary, bonus upto More ❯

Proven record of complex software delivery in the Interest Rates domain Excellent Java 21, Spring Boot, strong practical experience with containers, REST APIs, and WebSockets Strong experience of Agile, SCRUM, and test-driven development processes Strong leadership experience (at least 5 years of leading a team) Contact Ciara Clarke at More ❯

of Python, Go, or Java (Backend/API); confident JS/TypeScript skills (Frontend). Extensive practical experience with integration protocols (REST, gRPC, MQTT, WebSockets). Solid database skills (PostgreSQL, SQLite). Proficiency with containerisation technologies. Experience building simple desktop applications using Wails, Electron, or Tauri. Familiarity with edge/ More ❯

delivering front-end applications in electronic trading environments Strong understanding of performance optimisation and low-latency UI design Experience with real-time data technologies (WebSockets, FIX, etc.) Familiarity with containerized front-end platforms such as OpenFin is a plus Prior exposure to Fixed Income products (Rates, Credit, Bonds) or other More ❯

using a framework like NextJS Proficiency in writing safe, strict and well tested code in Typescript Seasoned experience with different protocols like HTTP and websockets Used to developing complex services from requirements to shipping Willing to learn new skills and really get stuck in Bags of common sense with the More ❯

using a framework like NextJS Proficiency in writing safe, strict and well tested code in Typescript Seasoned experience with different protocols like HTTP and websockets Used to developing complex services from requirements to shipping Willing to learn new skills and really get stuck in Bags of common sense with the More ❯

and accuracy. Core Tech Stack Languages: Python (Python 3.10+), JavaScript and TypeScript for frontend Tools: RabbitMQ and ZeroMQ for messaging; PostgreSQL for data storage; Websockets for frontend communication Environment: Linux servers Observability: Prometheus, Grafana, Zabbix Benefits: Working alongside other extremely talented and driven engineers Extremely lucrative salary, bonus upto More ❯

the in-house team in the near term. Tech Environment Stack: Next.js, Node.js Infrastructure: MongoDB Atlas, Heroku Tools: Auth0 (auth), AWS S3 (file storage), WebSockets Voice & AI: Twilio, OpenAI, ElevenLabs Who We’re Looking For Be a senior full-stack engineer with experience in fast-moving startup environments Have a More ❯

mobile architecture using modern patterns Work closely with design & product to ship polished, scalable user interactions Essential Qualifications: Experience with real-time protocols (eg. WebSockets gRPC, MQTT, SSE or similar) Experience with implementing on-device machine learning (eg. PyTorch Mobile, ML Kit, TensorFlow Lite) Strong understanding of Android performance: lifecycle More ❯

experience (games industry preferred) Strong coding skills in C++, C#, Go, or Node.js (C C# ideal) Deep understanding of distributed systems, real-time networking (WebSockets, RPCs, REST, gRPC) Experience with cloud platforms (AWS, Azure, or GCP) Familiarity with matchmaking, player sessions, anti-cheat systems Database experience across SQL and NoSQL … Ltd. Langham Recruitment Ltd acts as an employment agency and is registered in England and Wales (reg 11525223). Keywords: C++, C#, Go, Node.js, WebSockets, RPCs, REST, gRPC, AWS, Azure, GCP, PostgreSQL, Redis, MongoDB, PlayFab, AccelByte, Nakama More ❯

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 More ❯

Senior Frontend Engineer | FinTech/DeFi | Up to £120,000 p/a + Bonus + Liquid Equity 💻 Senior Frontend Engineer - Up to £120,000 per annum 🚀Rising player in Decentralised Finance (DeFi) 💰Up to £120,000 p/a More ❯

Role Overview As a quantitative developer, you will play a pivotal role in building and optimising our quant trading systems, backtesting infrastructure, and research tools. You will collaborate closely with quantitative researchers, traders, and engineers to translate complex financial models More ❯

Location: Hybrid, West Hampstead, London (2 days+/week in-office, non-negotiable) Salary: up to £75-£80k per annum About us: We're a Y-Combinator backed startup, founded by experienced engineers and repeat founders from companies like Revolut. More ❯