Lovable★4.0 (43)· London

Uses Go, Rust, TypeScript; AWS, Azure, Google Cloud, Cloudflare; Kubernetes, Terraform, Temporal, OTEL, CI/CD; PostgreSQL, ClickHouse, Firestore, Spanner, BigQuery. Builds the platform for Lovable Enterprise enabling secure, cloud-agnostic deployment, defining architecture for sandboxing, networking, encryption, identity, and mentoring engineers.

Work with Java, GitHub Copilot, Devin.AI, Citi Squad, Stylus Workspaces (Gemini, OpenAI, Claude, Llama), Docker, Kubernetes, and CI/CD. Build high-performance, real-time FX risk management systems for a greenfield platform with a 10+ year strategic commitment. As a VP, lead end-to-end delivery and technical direction.

You'll work with FastAPI, TypeScript, React, OpenAI/Anthropic, PostgreSQL, and Azure to build AI agent systems—from voice interfaces to workflow orchestration—for aircraft maintenance and manufacturing. Fleetcraft builds infrastructure that helps technicians maintain and manufacture aircraft.

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.

Koinly★3.0 (1)· London

You will work with TypeScript on Bun, RabbitMQ, Redis, PostgreSQL, Vitest, Sentry, and Rust. The team owns the distributed data-processing backend that ingests, normalizes, and reconciles on-chain and exchange data for Koinly’s crypto tax calculation product.

You'll work with FastAPI, Pydantic, TypeScript, React, OpenAI/Anthropic, PostgreSQL, Turbopuffer, Promptfoo, and Azure. The team builds AI agent systems and core infrastructure for aircraft maintenance and manufacturing, from voice interfaces to workflow orchestration.

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.

Build with Python, Go, or Java on the backend, and React/TypeScript on the frontend, using PostgreSQL and non-relational stores, with Docker, Kubernetes, and cloud infrastructure (AWS, GCP, Azure). This role owns full-stack delivery of the B2B product—a campaign, device management, and insights platform for retail and brand partners—along with API design and distributed systems. The team includes engineers, product, and platform groups, working closely with the Head of B2B Product.

You'll work with Python and/or TypeScript, using full-stack JavaScript or backend Python. The role is a founding engineer at a stealth AI company backed by a £100M bootstrapped founder with three successful exits.

Lovable★4.0 (43)· London

Build enterprise deployments using Go, Rust, and TypeScript on AWS, Azure, and Google Cloud, with Kubernetes, Terraform, and Temporal. You will build the platform that allows large customers to run Lovable securely and at scale across every major cloud provider.

Build and own the machine learning models (propensity, uplift, contact strategy) that decide who, when, how often, and on which channel (voice, WhatsApp, email, SMS) Murphy's AI agents contact debtors to maximize recovery within legal limits. Work in Python, TypeScript, AWS, and PostgreSQL; design, run, and ship A/B tests and bandits on live traffic.

You'll build backend services and microservices using Rust, Go, Python, and Java for X Money, xAI's global payment network targeting 600+ million users. The role involves designing high-scale, low-latency distributed systems for payments, fraud detection, and compliance while collaborating with iOS, Android, and web teams on full-stack features in a startup-like environment.

You'll work with JavaScript, TypeScript, React, HTML5, CSS, and server-side rendering to build production web applications and responsive interfaces. As a founding engineer at Hyre AI Limited, you'll shape the frontend architecture from an early stage.

Build backend services in Java/Spring on AWS, working with event-driven systems (Kafka, event sourcing). You’ll join a pre-launch UK fintech building an AI-powered autonomous savings app, contributing to the money-movement engine, ledger, and APIs alongside the CTO.

Lead Front-End Developer with React and TypeScript, working on payment and point-of-sale technology for live events. Responsible for front-end architecture, design system, shared component library, payment flows, and real-time data integrations. Will mentor a small team and own tooling, standards, and CI/CD release pipelines.

You will work with JavaScript/TypeScript, SQL/NoSQL databases, and cloud infrastructure across frontend, backend, data pipelines, and APIs. The team builds an AI-powered investment platform for retail investors to create, backtest, and automate personalized strategies. The FCA-authorised company also integrates with financial data, payments, and custody platforms.

Wise★3.5 (42)· London

Build backend

You'll work with Python, TypeScript, Java, Go, and cloud environments (AWS, Azure, GCP) to build the UK's first zero-commission Options and Stocks trading platform. You'll join a founding engineering team of 4, owning core features end-to-end.

You’ll work with Kotlin, TypeScript, Azure, Terraform, Temporal, and Postgres to build large-scale batch processing infrastructure, an LLM gateway, and enterprise-grade auth/observability for an AI operating system that automates analysis and documentation of complex enterprise software environments. You join a small, talent-dense backend team owning significant core platform components.

You'll work with Python (FastAPI), Postgres, Redis, Docker/Kubernetes, and AWS. As a founding London engineer, you'll own production services and build scalable backend systems for a commodity e-commerce and electronic trading platform provider.

You'll build backend services powering Happl's AI-driven employee benefits platform using Go and TypeScript, working with REST APIs, PostgreSQL, and cloud infrastructure. The role focuses on designing scalable systems for benefits, allowances, payments, and reporting across a global customer base. You'll collaborate with product and frontend teams to ship end-to-end features while improving reliability, security, and observability.

You will work across the full stack using Python, TypeScript, Java, or Go in cloud environments (AWS, Azure, GCP). The team is the founding engineering team of four building the UK’s first zero-commission options and stocks trading platform.

You will use Python or JavaScript with low-code platforms like Zapier or n8n and integrate LLMs and AI via REST APIs. You will identify and automate manual inefficiencies across the business, building internal automation ecosystems at Goodlord, a platform used by around 3,000 letting agents.

Work with Next.js (App Router), TypeScript, and React to own and ship the front-end of a SaaS platform. CultureTest provides company-specific, scenario-based behavioural screening for hiring teams. You will collaborate with the CTO on API contracts, system design, and frontend architecture.

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.