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.

Koinly★3.0 (1)· London

Work with React 19, TypeScript, TanStack (Router, Query, Table), Radix UI, Mantine, Tailwind CSS v4, Vite, Vitest, Storybook, Highcharts, Sentry, Bun, and RabbitMQ on a data platform that reconciles crypto transactions and tax obligations for Koinly’s web application, with a React Native mobile app joining scope later.

Senior WordPress Developer role: build bespoke WordPress sites and apps using PHP, MySQL, ACF, WooCommerce, Gutenberg, JavaScript (ES6+), SASS/SCSS, Git, Composer, npm, Vite, CI/CD. You’ll also drive AI-assisted development (RAG, MCP, Copilot) and mentor junior developers.

You will work with Java, Selenium, RestAssured, Gherkin, and Jira/Xray to design and maintain automated test frameworks. This cross-functional Agile squad develops complex healthcare software systems that support Genomics England’s genomic medicine and research initiatives for the NHS.

Design, build, and deploy quantitative models using Python, R, and libraries (numpy, pandas, scikit, pytorch, tidyverse, caret, ggplot) plus NLP tools, SQL, AWS, Sagemaker, DataBricks, Snowflake, MLFlow, and Weights & Biases. The team creates systematic country risk analytics and ML/NLP pipelines for BMI’s market insights, supporting clients in risk assessment.

As Principal SDET, you will lead quality engineering using C#, Playwright, and Selenium for test automation across UI, API, and integration layers. You will drive the quality strategy for a financial services organisation undergoing a major business and technology transformation. This is a senior technical leadership role, not managing a specific team size.

Work with Python, BeautifulSoup, Selenium, and Apify to scrape dynamic web content, extract data from complex structures, and deliver structured datasets. You will join the Tendem project, driving specialized data scraping workflows for real-world applications. LLM and AI frameworks are also used to enhance automation.

Fitch Solutions★3.0 (2)· London

As a Data Scientist at BMI (a Fitch Solutions business), you will design, build, and deploy quantitative models using Python and R (e.g., numpy, pandas, scikit, pytorch) to power advanced analytics. You will develop and maintain ML/NLP and data pipelines, working with Economists and Analysts to build risk models and generate insights from structured and unstructured data.

American Express★4.1 (9.7k)· London

You will work with Kotlin/JVM, Java, React, Postgres, MongoDB, Redis, Docker, Kubernetes, and GitHub Actions. The Financial Insights and Tools group builds financial analysis software for American Express customers, powered by APIs and underlying platforms for web and mobile applications.

You will work with Java, JavaScript, Python, or C#; open-source frameworks like Cypress, Karate, PlayWright, or Selenium; CI/CD pipelines in Azure DevOps; and JMeter for performance testing. As part of an agile team, you’ll help clients achieve business transformation goals through automated and manual testing.

Work with Kotlin/JVM, Java, React, APIs, Postgres, MongoDB, Redis, Docker, Kubernetes, GCP GKE, AWS ECS/EKS, Ktor, Spring, and GitHub Actions. The Financial Insights and Tools group builds customer-facing web and mobile features that aggregate and analyze financial data to enhance personal finance management.

You will work hands-on with Java, Kafka, Kubernetes/OpenShift, caching solutions, REST APIs, Spring Boot, SQL, Git, and Gradle/Maven within a high-volume message processing environment for a trading client in the financial services domain.

Use Selenium with C# to build and maintain automation frameworks, create regression suites, and perform functional/integration testing. As the first UK-based QA for a financial services firm's growing European technology team, you'll collaborate with an Agile squad and a US QA team.

American Express★4.1 (9.7k)· London

Work with Kotlin/JVM, Java, React, Postgres, MongoDB, Redis, Docker, Kubernetes (GCP GKE, AWS ECS/EKS), GitHub Actions, Ktor, and Spring. The Financial Insights and Tools group within Digital Banking builds financial analysis and planning applications for American Express customers on web and mobile, powered by APIs.

Develops and maintains Java-based full-stack applications. Works with AWS cloud services, Kafka for messaging, and containerisation tools such as Docker. Versions 1 delivers technology solutions for global enterprise clients.

Lead a team using React, Node.js, Express.js, AWS, SQL, NoSQL, Docker, Kubernetes, and Jenkins. You will design scalable, cloud-native microservices architectures as a Technical Lead for Version 1, a consultancy delivering IT solutions for global brands. This role oversees a development team and ensures adherence to best practices.

Python, SQL, PyTorch/TensorFlow, Hugging Face, LangChain, MLflow, Docker, Kubernetes, AWS/Azure/GCP, Databricks, Snowflake. You will build, deploy, and optimize ML and Generative AI solutions, including RAG systems, AI agents, and LLM applications.

Work across the stack with React, TypeScript, and Node.js or Golang on privacy-focused systems and architecture that keep users' location data inaccessible. As part of Wheely's small core-engineering team, you'll collaborate with Product Managers, Designers, and Software Engineers to shape solutions from concept through production.

You will work with Vue.js, Vuex, Pinia, Vite, TypeScript, and real-time data tools (WebSockets, SSE) to build high-performance trading UIs. The role is on the team that continuously improves Interactive Brokers’ critical platform for automated trade execution and custody across global markets.

This Test Manager role oversees end-to-end testing for large insurance programmes using test management tools like JIRA, with essential Agile/Scrum experience and knowledge of QA methodologies, test automation, and defect management. The position coordinates testing processes across major initiatives at Arch Insurance, collaborating with developers, QA engineers, product managers and stakeholders to ensure quality, compliance and UAT delivery. The role requires significant leadership experience managing large testing implementations and driving continuous improvement across testing practices.

Develop, maintain, and optimize automation frameworks for critical banking payment systems using Selenium POM, Karate, and APIs. Support UI, API, Database, Messaging, and Integration testing layers by designing reusable automation libraries and framework components. Drive framework modernization initiatives to ensure scalability.

Grid Dynamics★3.4 (19)· London

Build high-performance React and TypeScript trading applications using WebSockets, RSocket, and streaming market data. Work within an embedded team modernising a Tier 1 investment bank’s electronic trading platforms, migrating legacy Angular apps to React. Collaborate with backend Java engineers on mission-critical front-office systems.

Develop production code using Java 8+, Spring (Core, Boot, Integration), Kafka, Oracle/MySQL, and tools like JUnit, Mockito, Cucumber, Selenium. This role designs and secures scalable tech products for a bank, handling system design, microservices, and operational stability in an agile environment.

Version 1★3.9 (39)· London

Design and implement scalable software using React, Node.js, Express.js, AWS, SQL, NoSQL, Docker, Kubernetes, and Jenkins. As a Technical Lead, you will architect solutions, mentor development teams, and guide projects for Version 1, an IT consultancy delivering digital solutions for global brands.

The role uses OutSystems, PHP, SQL Server, SSIS, Power BI/Tableau, Git, and IBM RPG to design and maintain business-critical applications. Working within a small IT team, the developer handles the full software development lifecycle, modernizing internal systems and integrating third-party software.