Citi★3.9 (21k)· London

Work with Solidity, Web3J/Web3JS/Ethers.js/Viem, Java/Spring, Node.js, and blockchains such as Ethereum, Hyperledger Besu, Canton, and Solana, using Hardhat/Foundry/Truffle for testing. Contribute to Citi's Integrated Digital Assets Platform (CIDAP) building Web3 components for tokenization, smart contracts, and on-chain settlement.

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.

Backend engineers use Python, Django, Django-REST-framework, GraphQL (Graphene), Celery, Postgres, and AWS (Packer, Consul, Terraform). They build and maintain the AI-driven energy management platform that powers utilities and optimises renewable generation. The global engineering team is around 1,400 people.

Reward Gateway★4.4 (11)· London

Define and champion the architecture vision for the Engagement Business Unit, working with global architecture and engineering leaders. The role involves leading architecture governance, establishing reusable patterns, and driving the adoption of AI-enabled engineering practices across APIs, microservices, event-driven systems, and data streaming platforms like Kafka. You'll partner with product and engineering teams to deliver scalable cloud-native applications and improve CI/CD pipelines and software delivery practices.

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.

Spotify★4.1 (116)· London

You will work with React, TypeScript, Java, GraphQL, PostgreSQL, and Google Kubernetes Engine (GKE) to build end-to-end solutions. The team builds Groove, a platform that helps thousands of employees plan, coordinate, and deliver work across Spotify.

Design, configure, and develop HR web applications using React, Next.js, and the HRSD platform. Build reusable UI components, integrate with REST/GraphQL APIs, and participate in CI/CD processes alongside product managers, designers, and backend engineers.

You will work with Java, Spring Boot (Spring Batch, Spring Cloud), microservices, REST APIs, GraphQL, Azure Cosmos DB, and Confluent Kafka. The team builds AI-driven digital products and services that support employees and HR stakeholders.

Working with Python, SQL, AWS, and APIs like GraphQL, gRPC, and REST, you will productise ML models and manage data workflows in cloud infrastructure. The HealthTech team focuses on ethical AI to improve patient care outcomes.

MAREX★3.2 (6)· London

You will work with C# .NET, JavaScript, TypeScript, React, Node.js, GraphQL, Docker, NoSQL/RDMS databases, and AWS cloud services (ECS/EKS, Lambda, S3, RDS, API Gateway). The team builds and maintains applications to strengthen the company’s market-making capabilities and improve operational efficiency across multiple asset classes and geographies.

You will work with React, TypeScript, Next.js, Jest, Cypress, CSS-in-JS libraries, Git, and GraphQL. You will join the Customer Apps team to build and scale customer-facing applications for payment device management, loyalty schemes, and more at Dojo, the UK's largest payments acquirer.

Tripadvisor★3.9 (142)· London

You will work with Kotlin, Coroutines, Jetpack Compose, Cursor, GraphQL, and MVVM in a clean-architecture modular layout. You’ll join the Tripadvisor Experiences mobile team, focusing on Android app development with occasional backend microservices work.

Tripadvisor★3.9 (142)· London

Android Engineer role working with Kotlin, Coroutines, Jetpack Compose, Cursor, and GraphQL in a modular, clean-architecture MVVM layout. You will build and release code for the Tripadvisor Experiences mobile app, collaborating with product and designers on the full software lifecycle. This is a full-stack role where you primarily develop Android systems, with occasional back-end projects.

Senior Software Engineer designs and maintains backend services and APIs using Java, Python, and Node.js, working with microservices and Spring Boot. The role involves building REST, GraphQL, and SOAP APIs, using relational and NoSQL databases (MySQL, PostgreSQL, Oracle, Redis), and performing cloud-native development in AWS environments. This position supports financial systems and integrations within the leading global business aviation company, Vista.

Build and support scalable enterprise integrations using Workato, APIs, webhooks, REST, SOAP, GraphQL, OAuth, JSON, XML, SQL, JavaScript, Python, and Workato formulas. Integrations span finance, HR, CRM, document management, and analytics platforms. No team size specified.

Senior Full Stack Engineer working with TypeScript, React/Next.js, GraphQL and modern cloud infrastructure on an AI-powered platform that automates data collection, reporting and collaboration for investment firms. You join a small engineering team and collaborate directly with founders.

Work with TypeScript, LangChain, React, GraphQL, Prisma, Temporal, and LlamaIndex to build AI agents that automate high-stakes banking workflows. You will own features end-to-end, architecting a core platform that orchestrates AI, customers, and humans to replace legacy banking bottlenecks.

Design data architectures using AWS, Azure, Kafka, Kinesis, Airflow, NoSQL (MongoDB, DynamoDB, HBase, CosmosDB), GraphQL, Snowflake, DataBricks, SQL, and Python. You will drive the technical direction of Digital Identity & Fraud products at LSEG’s Risk Intelligence division, mentoring team members and aligning architecture with enterprise strategy.

Build scalable backend services using modern Java, TypeScript, React, and Next.js, and design GraphQL/gRPC APIs with PostgreSQL on the Monaco squad. You will create internal products enabling Spotify teams to launch, configure, and manage Premium offers, subscriptions, and pricing.

You'll work with Python (Django/FastAPI), React, TypeScript, PostgreSQL, Azure, Docker, and CI/CD to build customer-facing applications and APIs. The team is part of Oritain, a product origin verification company.

STINT★3.6 (65)via Jack & Jill· London

Build and maintain core systems using Python (Django), Go, Flutter, GraphQL, PostgreSQL on AWS/EKS with DataDog and GitLab. You’ll join a cross-functional product pod powering Stint’s platform that combines a flexible student workforce with AI for hospitality brands.

You will work with Python, SQL, PostgreSQL, Dagster, Git, and CI/CD tools like GitHub Actions, plus Docker, Kubernetes, and REST/GraphQL APIs. This computer-vision startup builds scalable data pipelines and infrastructure to power next-generation products across cloud, AI, and embedded systems.

You will build frontend applications using React and TypeScript, develop reusable UI components, and work on real-time features with WebSockets and GraphQL. The company builds a suite of real-time products for enterprise customers in specialized financial markets. The small, experienced engineering team offers significant ownership from day one.

Spotify★4.1 (116)· London

As a Fullstack Engineer on the Monaco squad, you'll build end-to-end features with Java 17+, TypeScript, React, Next.js, and PostgreSQL, and develop GraphQL and gRPC APIs for Spotify's subscription business. You will create internal tools that enable teams to launch, configure, and manage Premium offers globally.

You will work with Angular, TypeScript, HTML5, Java, Spring Boot, REST/GraphQL, MongoDB/MSSQL, Kafka, and AI coding agents like Copilot and Devin. This role is on Citi’s Banking Technology team building a microservices-based web platform for senior bankers as part of the Opus Capital Management strategic transformation.