Citi★3.9 (21k)· London

You will work with TypeScript, React, HTML5, CSS, JavaScript (ES6+), Chromium/Electron/OpenFin, FDC3, REST/WebSocket APIs, Kafka/Solace/Tibco, and CI/CD with Jenkins. The team delivers pricing solutions and trading GUIs for Citi’s Foreign Exchange business. You will provide technical leadership, mentor junior engineers, and drive AI integration.

You will lead AI and automation initiatives using n8n, Claude, Zapier, and API integrations. As a product leader at a London-based eCommerce and paid media consultancy, you will drive efficiency across teams by automating workflows and building internal AI-powered tools. You will manage a small team of automation specialists or developers.

You'll build GTM systems using HubSpot, DealHub, Gong, Clay, APIs, webhooks, Python, JS, SQL, and AI tools (ChatGPT, Claude, Copilot, Gemini, Notion AI). This role designs end-to-end systems—from lead enrichment and routing to quote-to-cash—for Monta’s EV charging platform, including prototyping AI agent workflows.

You'll own Ravio's brand across marketing channels, using Figma to build libraries, templates, and AI-assisted design workflows. The company provides a real-time data platform that helps companies manage compensation data, and you will design campaigns, landing pages, reports, and data visualizations for this B2B SaaS product.

You'll work with TypeScript, React, SQL, Amplitude, GrowthBook, PostHog, LaunchDarkly or Statsig, and Customer.io or Braze. The company is building a senior AI employee for small-business owners that drafts client work from existing tools. You own the activation funnel, experiment framework and retention loops as the first growth engineer on a small senior team.

You'll use PHP, Laminas, Mezzio, Stripe, and AI tools like Claude Code. You'll build a new payments product and maintain existing payment integrations for Ticket Tailor's event ticketing platform. The team consists of two engineers alongside a Product Manager.

You'll work with PHP, Laminas, Mezzio, AI tools like Claude Code, Cloudflare, GitHub Actions, Datadog, and Amplitude. You'll build a new payments product and extend existing payment integrations for Ticket Tailor, enabling event organisers to get paid. You'll be part of a small team with two engineers alongside a Product Manager.

Build backend systems with Kotlin or Java, Kafka, PostgreSQL, Redis, and microservices for a crypto savings and crypto-backed lending platform. This hands-on technical lead defines architecture, remains close to the code, and leads a small team of engineers.

Build features across a dual-stack backend (TypeScript, C#, .NET) and microfrontend React apps, using AWS (ECS, Lambda, SQS, DynamoDB, DocumentDB), Terraform, SST, and AI coding agents. You'll evolve a B2B SaaS platform that powers UK housing transactions, adding new AI capabilities alongside a mature .NET foundation.

Lead UI Developer role using TypeScript, React, RxJS, WebSockets/SSE, GraphQL, Protobuf, Flatbuffers, Jest/Vitest, React Testing Library, Playwright, and AG Grid. You will own the front-end architecture for a real-time Single Dealer Platform used by Sales, Trading, and institutional clients globally, building low-latency trading applications for market data, pricing, RFQ, and trade capture.

You will build scalable server-side logic using JavaScript, TypeScript, and Node.js in a microservices architecture on AWS with Kubernetes, Terraform, Kafka, and Snowflake. You will join the MMH team within the Martech domain, which orchestrates campaign delivery across email, push notifications, and personalised content for all Sainsbury’s Group brands. The team includes 7 engineers.

Lead Software Engineer for the PRIIP Cloud platform, owning full-stack development with TypeScript/Node.js, React, Java/Kotlin, REST APIs, event-driven architectures, AWS, Docker, and Kubernetes. The team builds a cloud-based PRIIP documentation and reporting system for regulated financial services, collaborating with compliance, quant, and product specialists. This role leads a multidisciplinary team of engineers and subject matter experts.

Develop backend services using Node.js, Python, Java, C#, PHP, and Ruby on Rails, with databases including MySQL,

TypeScript, React, Node.js, Bun, Kubernetes, and AWS. The team builds web apps, back-office systems, and tooling for financial product comparison across money.co.uk, Uswitch, and Confused. As a Staff Software Engineer, you set technical direction for Financial Services.

You will work with JavaScript (TypeScript), React, Redux, RX JS, NPM/Yarn, webpack, CSS, HTML, Azure DevOps CI/CD, and Java. As a senior developer on the FM Digital Channels team, you will build Blade, the bank's strategic in-house pricing, execution, and trade processing platform for Financial Markets.

Work with Java/Spring, React, JavaScript/TypeScript, CI/CD pipelines, and distributed systems. You'll join the Account Integrity team building a globally scalable fraud prevention engine to protect customer accounts and prevent financial crime using machine learning and real-time monitoring.

Design, develop and support D365 solutions across Power Platform and Dataverse, using C#, JavaScript, Power Automate, Power BI, and Power Apps. The role supports a major transformation programme, enhancing business processes and driving Dynamics adoption across the organisation.

Lead Python Developer role using Core Python, Flask, VueJS, JavaScript, CSS, HTML, SQL, AWS, Terraform, Docker, and serverless components, with CI/CD and Agile practices. The developer builds, enhances, and supports production applications within UK public sector programmes, collaborating with delivery, product, and data teams.

You’ll build cloud-native applications for a leading global financial institution, using Java with Spring Boot and React to support critical financial operations.

Full-stack Java development on Linux/Unix, using AI coding tools like Claude Code, Windsurf, Devin, or GitHub Copilot. The role is for Ascendion, a technology services company.

Use object-oriented programming (Java or C#), Salesforce Lightning, Force.com, Apex, SOQL, JavaScript, Git, Jira, IntelliJ, CI/CD, and Salesforce REST APIs. Hackajob Ltd is a platform that connects developers with job opportunities. This Salesforce Developer role delivers complex business and technical requirements on the Force.com platform.

Samsara★3.6 (32)· London

Samsara interns work on the Connected Operations Cloud, building backend infrastructure in Golang, web clients with TypeScript/React and GraphQL, mobile with React Native, or embedded software for IoT devices. Projects involve scaling data ingestion, real-time data processing, and creating actionable insights for industries like transportation and agriculture.

You will work with Python, AI coding agents (e.g., Claude Code, Codex), and potentially AWS, Kubernetes, and Temporal. Unitary builds Virtual Agents — AI-powered software workers that automate complex workflows end-to-end in customer tools, focusing on commercial insurance, marketplaces, and primary healthcare.

You will build and evolve customer-facing interfaces for AI Virtual Agents using React, TypeScript, Next.js and Vite, and refactor the frontend into a scalable platform with a shared component library and design system. Unitary’s factory builds custom operations agents that complete complex workflows end-to-end in customer tools.