Senior Full Stack Engineer (Amsterdam, NL)

Senior Full Stack Engineer

Join the Team

Senior Full Stack Engineer

Amsterdam

Full-time

Senior (5+ YOE)

Product Engineering

Build features end to end, from the data model to the production UI, on a platform that collects 100M+ data points a day from ChatGPT, Claude, Perplexity, Gemini, Google AI Overviews and the other major AI engines.

Role Overview

As our Senior Full Stack Engineer, you'll own features from start to finish: scope them with product and design, build the schema and the API, ship the UI, and keep an eye on them in production. The team is small, you get real autonomy, and code ships the same day. You'll work directly with the founders, with no management layers between you and the decisions.

About Promptwatch

Promptwatch is building the leading platform for Generative Engine Optimization (GEO), helping brands understand, measure, and improve how they appear across AI search platforms like ChatGPT, Gemini, Claude, Perplexity, and AI Overviews. Brands like Yelp, Typeform, Fireflies, and Shutterstock, along with agencies worldwide, rely on Promptwatch to turn AI Search into a measurable growth channel.

Making that possible takes serious engineering. We collect AI answers from the live interfaces of each engine, routed through geo-located proxies so a monitor sees exactly what a user in a given country, state, or city would see. We stream AI crawler logs in real time from CDNs like Cloudflare, Fastly, Akamai, and CloudFront. And we index every customer's site into Elasticsearch with paragraph-level embeddings, so we can re-run the same query fan-out AI engines use and test whether their content can answer it.

The stack is a TypeScript monorepo (React, Next.js, Fastify, Prisma, tRPC) on Postgres, Elasticsearch, Redis, and ClickHouse, running on Google Cloud. It's split into several services, including the API server, an AI gateway, ingest pipelines, and log processing, and each one has its own scaling problems.

What You'll Do

• Take features from problem definition to production: scope with product and design, build the schema, write the API, ship the UI, and monitor it once it's live
• Design and improve the data pipelines that move millions of records a day through Postgres, Elasticsearch, Redis, and ClickHouse
• Build and run services on Google Cloud (Cloud Run, Pub/Sub, CI/CD) and keep them observable with Sentry, structured logging, and custom dashboards
• Help shape how we work: code review standards, testing (Vitest, Playwright), and technical direction
• Work directly with the founding team on what to build and how

What We're Looking For

• 5+ years of experience building production web applications, with ownership of features across frontend and backend
• Strong experience with TypeScript, React, and Node.js (we use Fastify, but experience with other frameworks carries over)
• Comfortable designing and querying relational databases (we use Postgres with Prisma)
• Experience building APIs, whether tRPC, REST, GraphQL, or a mix
• Familiarity with job queues, async processing, or event-driven architectures
• You write tests and take code review seriously
• Comfortable working in English with Product, Design, and the founders

Nice to Have

• Elasticsearch, ClickHouse, or other analytical datastores
• Embeddings, semantic search, or retrieval (RAG) systems
• Working with LLM APIs (OpenAI, Anthropic, Google)
• Large-scale scraping, log processing, or high-volume ingest pipelines
• Data visualization (Recharts, D3, or similar)
• Monorepo tooling (Turborepo, pnpm workspaces)
• Google Cloud Platform
• Experience at an early-stage, fast-growing startup

Compensation & Benefits

• Competitive salary
• HQ at Leidseplein, in the heart of Amsterdam
• Team off-sites and company events
• Sports activities, including our own run club
• Growth opportunities as our engineering team grows
• A real say in product and technical direction
• A well-maintained codebase: strict TypeScript, Oxlint linting, thorough types
• Time and budget for learning: conferences, courses, books

If you're excited about owning features end to end and building a platform that grows with Promptwatch, we'd love to hear from you.