You will build a fully bespoke blockchain from scratch using Rust, C++, CUDA, Python, Shell for the protocol layer; Solidity, Foundry, Hardhat for smart contracts; and TypeScript with React, Next.js, Node.js for frontends. This greenfield project powers Arena Entertainment’s digital entertainment platforms, spanning gaming, DeFi and Web3.

JS/TypeScript, React, Node, Azure, infrastructure as code, and AI tools. You’ll build the compliant data layer for community healthcare, enabling pharmacies to use patient data to grow revenue and relationships within NHS-assured clinical systems. You’ll be the first engineer, working directly with the CEO and founding team on product decisions.

Zaizi★4.0 (5)· London

Building mission-critical web apps, APIs, and microservices (TypeScript, React, Node.js, Python) plus native Android/Kotlin tactical systems with AIDL IPC and CoT routers for MoD programmes. Working on edge platforms (TAK) with CI/CD (Docker, GitLab CI) and NCSC Secure by Design standards. Mentoring mid-level engineers.

National Gas★0.0 (10)· London

Work with ASP.NET, ASP.NET Core, .NET, SignalR, WebRTC, SQL Server, MariaDB, Entity Framework Core, Dapper, Azure, Docker, and CI/CD tools to maintain existing web platforms and build a new real-time operational system featuring mapping, GPS, and audio calling.

CrowdStrike★3.8 (54)· London

You will work with TypeScript, Vite, Playwright, Vitest, GitLab CI, and Jenkins to lead the shared UI quality platform at CrowdStrike, a global cybersecurity leader. The platform consolidates testing frameworks, CI pipelines, and quality signals that hundreds of UI engineers rely on across the organization.

You’ll work with JS/TypeScript, React, Node, and Azure, implementing infrastructure as code and using AI tools throughout. PharmLogic provides a compliant data layer for community healthcare, letting pharmacies use patient data for growth and communications—NHS-assured and live in hundreds of pharmacies. You own product decisions end to end as the first engineer, working directly with the CEO and founding team.

Build Python (FastAPI/Flask) features for the NHS Digital Onboarding Service (DOS) within a serverless architecture, paired with a NextJS/React client frontend. The service is part of the NHS API Platform.

Senior UI Software Engineer role at Citi building trading GUIs for the Foreign Exchange business, covering full development lifecycle with technical leadership. You will use TypeScript, React, JavaScript, HTML5/CSS, FDC3, REST/WebSocket APIs, Kafka/Solace/Tibco, and CI/CD tools like Jenkins, with desktop container experience in Chromium/Electron/OpenFin.

You will work with C#, .NET (.NET Core/8+), SQL

You will work with C#, .NET, Azure, GitHub Actions, Octopus Deploy, CI/CD pipelines, front-end frameworks, and observability tools like Azure Monitor, Datadog, or Grafana. As part of a cross-functional digital product team at Canada Life, you will build and run product features across the full stack, living a "you build it, you run it" philosophy.

Lead zero-to-one development of a fintech platform for emerging-market payments, using TypeScript, React, and Node to build ledger, custody, and settlement systems. You'll architect full-stack features integrating digital assets with traditional banking rails.

You will work daily with TypeScript, React, and Python across the full DeepEditor stack. The product is an AI-powered performance editing tool for Hollywood studios. As the technical anchor, you will mentor a growing team of fifteen engineers.

Lead Software Engineer role: leads a hands-on engineering team building greenfield applications using C#, .NET, Angular 16+ within a global energy trading company.

You will work with Python, AWS, and Kubernetes supporting the Forward Deployed Engineering team at a pre-seed voice AI startup building infrastructure for emerging markets, processing thousands of daily calls with proprietary speech models.

Build AI-enabled products using Python, TypeScript, Java or Go at a YC-backed AI start-up. Work directly alongside founders to ship customer-facing solutions and shape both product and engineering culture from day one.

You will work with Python, Node.js, PyTorch, OpenAI/Anthropic/open-source LLMs, SQL & NoSQL, Kubernetes, and Docker. You own the inference and orchestration layer for a proactive smart assistant that handles multi-step reasoning, tool calls, and long-running workflows, turning model capabilities into stable, production-grade APIs.

Build and ship AI features using Python, PyTorch/JAX, LLMs (OpenAI-style APIs, LLaMA, Qwen), vLLM, and vector DBs. You'll work on a proactive smart assistant that handles long-running workflows, persistent context, multi-step reasoning, and external tool interaction for everyday users.

You will work with TypeScript, React, Next.js, Nest.js, AWS and Vercel to build Kiki Club’s trust-based subletting platform. As the third founding engineer, you will own full-stack development of an AI-driven marketplace that automates trust-based matching.

You will use TypeScript, Next.js, Tailwind CSS, Motion, and Figma to build and own Attio’s marketing website. You’ll work within Studio, a multidisciplinary creative team, to launch product experiences and campaigns for the company’s CRM platform. This is an individual contributor role, with mentorship of other design engineers as the team grows.

VueJS 3, JavaScript (ES6), HTML5, CSS3 (SASS), RESTful APIs, GIT, Azure DevOps (CI/CD), Jest, Cypress/Playwright. Build and maintain modern web applications, developing reusable UI components and ensuring responsive, accessible, performant frontends.

Tecknuovo★0.0· London

You'll work with React, TypeScript, Node.js and/or Python, AWS or Azure, infrastructure-as-code, containerised workloads, CI/CD pipelines, and relational and NoSQL databases. You'll deliver end-to-end features across frontend, backend, and cloud for cloud-native digital services in government and enterprise environments, working in a high-performing Agile delivery team.

Python (FastAPI), TypeScript (Express), AWS (serverless), Terraform, Docker, PostgreSQL, DynamoDB, GitHub Actions, and React. The team builds the Orchestra control plane for data and AI, used by enterprises like Experian and Octopus Energy.

A Senior Full Stack Developer is needed to work with Angular, .NET, and legacy ASP.NET MVC. The role involves developing, enhancing, and modernising business-critical Front Office applications for an Investment Bank.

Full Stack Developer role using C#, .NET, JavaScript, and Umbraco for an established luxury travel company. The work involves a major transformation programme building web-based tools to automate operational tasks, improve pricing accuracy and management information, plus website enhancements.