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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Fullstack Engineer - **Company:** Capsa AI - **Location:** London, UK - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** Artificial Intelligence, Application Integration Architecture, Data Systems, Text Processing, Elasticsearch, Human-Computer Interaction, Python (Programming Language), PostgreSQL, RabbitMQ, TypeScript, ReactJS, Large Language Models, Technical Debt, Backend, Fastapi, Front End Software Development, Data Pipelines - **Published:** June 6, 2026 - **Apply:** https://uk.indeed.com/viewjob?jk=d1e75502b7986734 ## About the Role Do you have experience in TypeScript?, Do you have a Master's degree?, * Engineering depth across the stack. Four or more years building production software at a venture-backed startup or top tech firm. Owning features end-to-end, not just one layer. * You've shipped things that mattered. Entire products or features taken from ideation to production, with impact you can speak to. If you can't point to what changed because of your work, that's a flag. * The right technical toolkit. Strong Python and TypeScript, backend infrastructure like FastAPI, Postgres, ElasticSearch, and RabbitMQ, a solid React frontend, and enough LLM exposure to work confidently across the AI layer, or close enough that the gaps close fast. * Domain curiosity, not just technical ability. You go deep on the problem, not just the implementation. You care about what the product does for the person using it, and that shows in how you build. * Comfortable at pace. Fast-moving environments are where you do your best work, not something you tolerate. ## Description Get on a fast track to owning features that sit at the heart of a platform used by the world's leading PE firms. You'll work across the full stack - from backend infrastructure and data pipelines through to the AI layer and the interfaces analysts use every day. Whether you've built high-throughput data systems, worked on complex frontend products, or shipped across the stack at a fast-moving startup, you bring ownership most engineers don't have, and the job is to point that ownership at problems the industry has never had good tooling for. This isn't a place to pick up tickets. We hire engineers who want to shape what gets built, not just build what they're told. Responsibility comes fast, scope grows with performance, and the founding team is close enough that your best ideas will get heard. The opportunity * Build features the industry has never had. Design and ship capabilities that give our platform genuine investment expertise; end-to-end, from data model to user interface. * Own the full stack. Backend, infrastructure, AI integration, frontend. You move across whatever the problem needs, and you don't leave rough edges behind. * Expand what the platform can do. Integrate new data sources, extend the agent loop, and increase the depth and breadth of analysis our customers can perform. * Keep the codebase clean. Uphold rigorous standards across everything you ship. Tech debt is a tax on velocity, and you don't let it accumulate. Recent projects include * Agentic assistant with a finance-focused toolkit and advanced document authoring features * Scalable document ingestion and indexing pipeline * In-house, streaming-first agent framework * AI-assisted document editor, * Low ego, high ownership. You want to be part of building something that matters more than you want a title that says so. * Hungry and resilient. Start-up pace is the appeal, not the trade-off. Rejection doesn't slow you down. * Bias for action over planning theatre. You move with incomplete information and adjust as you go. * Genuinely curious about AI. Using it, breaking it, building it into how you work. ## Related Videos - [Watch Tests Go Brrrr! : Getting Started with Cypress in ReactJS](https://www.wearedevelopers.com/videos/282-watch-tests-go-brrrr-getting-started-with-cypress-in-reactjs) - [Developing the Backend with Stefan Lingler, CTO at Shpock](https://www.wearedevelopers.com/videos/100360-developing-the-backend-with-stefan-lingler-cto-at-shpock) - [Intro to FastAPI](https://www.wearedevelopers.com/videos/462-intro-to-fastapi) - [Inside Bitpanda's Tech Stack: Scaling a European Fintech Leader - Markus Dorner](https://www.wearedevelopers.com/videos/1979-inside-bitpanda-s-tech-stack-scaling-a-european-fintech-leader-markus-dorner) - [Meet Your New BFF: Backend to Frontend without the Duct Tape](https://www.wearedevelopers.com/videos/682-meet-your-new-bff-backend-to-frontend-without-the-duct-tape) - [Nest.js - TypeScript in the backend can also be clean](https://www.wearedevelopers.com/videos/1033-nest-js-typescript-in-the-backend-can-also-be-clean) ## Related Articles - [Navigating the AI Shift](https://www.wearedevelopers.com/magazine/629-navigating-the-ai-shift) - [Dev Digest 120 - Apple and peers](https://www.wearedevelopers.com/magazine/455-dev-digest-120-apple-and-peers) - [Dev Digest 121 - AI goes offline](https://www.wearedevelopers.com/magazine/456-dev-digest-121-ai-goes-offline) - [Dev Digest 159: AI Pipelines, 10x Faster TypeScript, How to Interview](https://www.wearedevelopers.com/magazine/563-dev-digest-159-ai-pipelines-10x-faster-typescript-how-to-interview) - [Dev Digest 132 - Binging WADFlix?](https://www.wearedevelopers.com/magazine/473-dev-digest-132-binging-wadflix) - [Dev Digest 131 - AI'm not sure about OSS](https://www.wearedevelopers.com/magazine/472-dev-digest-131-ai-m-not-sure-about-oss)