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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Full Stack Engineer - **Company:** The Radical - **Location:** New York, NY, United States - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** Query Performance, HTML, Java (Programming Language), Application Programming Interfaces (APIs), Artificial Intelligence, Business Logic, ARM Architecture, Automation of Tests, Big Data, C Sharp (Programming Language), C++ (Programming Language), Cascading Style Sheets (CSS), Databases, Continuous Integration, Extract Transform Load (ETL), Data Visualization, Software Debugging, Protocol Buffers, Python (Programming Language), MongoDB, Node.Js, Operational Databases, Svelte, Mockito, Next.js, Software Engineering, TypeScript, Web Applications, Web Application Frameworks, WebSocket, Rust (Programming Language), Tailwind, ReactJS, Rollup, Multi-Agent Systems, Backend, Vue.js, Webpack, AI Platforms, Gitlab-ci, Playwright, Sentry, Real Time Data, Figma, Graphql, Front End Software Development, Virtual Agents, JestJS, Api Management, Golang - **Published:** September 21, 2026 - **Apply:** https://www.careerjet.com/job/us84bacd243776b36a08d4a122786bf9eb/eaa ## About the Role Core frontend expertise * At least 4 years of professional experience with TypeScript, HTML, and CSS (ideally Tailwind), with a solid grasp of responsive and mobile-first design * Strong experience with modern frontend frameworks and reactive state management (Svelte/SvelteKit preferred; React or Vue acceptable if eager to learn Svelte) * Comfortable with modern build tooling (Vite, ESBuild, Rollup), Node.js, debugging, and performant frontend architecture (async data loading, security, Sentry) * Hands-on data visualization experience, ideally with D3 or low-level SVG/canvas graphics for custom scientific charts Backend and data fundamentals * Professional experience writing server-side code in a statically typed, compiled language (Go preferred; Java, C#, Rust, or C++ acceptable) and operating in polyglot monorepos * Experience designing and evolving API contracts (gRPC and Protocol Buffers preferred; REST or GraphQL acceptable) * Working knowledge of databases, data modeling, index query performance, and running production data migrations (MongoDB or document stores preferred) Communication and collaboration * Clear, precise communicator, especially when working across disciplines * Comfortable operating without a hard frontend/backend boundary: you pick up whichever layer the feature needs, and you know when to pull in a specialist * We actively use AI-assisted development and expect engineers to find their own productive workflows with these tools Pluses * Rendering large datasets without dropping frames: canvas-backed charts, virtualized tables and lists, or moving compute off the main thread with Web Workers * Familiarity with agentic systems (prompting, tool calls, MCP) or AI-frontend integration (e.g. Vercel AI SDK) * Experience delivering real-time data to clients: server-streaming RPCs, WebSockets, SSE, or database change streams * Testing experience: Playwright, Vitest, API mocking, linters and formatters * Observability practice: OpenTelemetry traces, metrics, and structured logs, or an equivalent * Advanced browser APIs such as the History API and structured concurrency in the browser * CI/CD for build and test pipelines (we use self-hosted GitLab CI) ## Description We're looking for a mid-level to senior Full Stack Engineer to build the software that powers materials discovery, from the interfaces scientists use down to the services and data models behind them. Reporting to the Director of Digital Experience and work closely with the rest of the software engineering team, most of your time will be spent on the frontend: crafting the interfaces scientists and engineers use to navigate vast datasets, turn dense experimental results into charts and interactive graphics they can actually reason about, interact with AI agents, and monitor autonomous lab experiments, all in real time. But we want you to be able to ship a feature end to end. In practice that means adding an RPC to Cortex (our Go backend), evolving the protobuf schema that Cortex shares with every client, and updating the data model in MongoDB, without waiting in line behind a specific backend engineer. This is not a design role, but you'll collaborate closely with product managers and designers to translate research workflows into intuitive, performant interfaces. What you'll do Frontend * Build and maintain complex, data-rich web applications using Svelte and SvelteKit * Implement high-fidelity UI from Figma designs with meticulous attention to detail * Build data visualizations for scientific research and analysis * Architect performant frontend systems that handle async data loading, real-time reactivity, and large-scale state management * Integrate frontend experiences with AI agent capabilities (tool calls, streaming responses, etc.) Backend and data * Extend Cortex, our Go backend, with new RPC endpoints and business logic, including server-streaming endpoints that push live lab state to the UI as experiments run * Design and evolve the protobuf schemas that define the contract between the backend and every client, keeping changes backward-compatible as generated code lands in TypeScript, Go, and Python * Model and update data in MongoDB: document schemas, indexes, and versioned migrations run against production data * Own features end to end, from schema through service, API, and UI, rather than handing off at the API boundary Across the stack * Write automated tests on both sides of the API and contribute to CI/CD pipelines, AI Engineer 4 (AI Foundations, VLM Customization) At Capital One, we are creating responsible and reliable AI systems, changing banking for good. For years, Capital One has been an… + 7 hours ago, AI Engineer 4 (Gen AI Platform Services: Agentic AI, Agent Guardrails, Agent Evaluation, Agent Memory) At Capital One, we are creating responsible and reliable AI systems, changing… + 7 hours ago, AI Engineer 5 (SDK's: Gen AI Evaluation and MCP) At Capital One, we are creating responsible and reliable AI systems, changing banking for good. 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