Senior Full Stack Developer

Homerun; Amsterdam; Hybrid; EUR 90,000 - 120,000; Full time

Benefits offered by this job

Office in central Amsterdam (hybrid)

Learning budget and conferences

Regular team off-sites

Job summary

Promptwatch is hiring a Senior Full Stack Developer to own features from concept to production within a TS monorepo (React, Next.js, Fastify) on Postgres, Elasticsearch, Redis, and ClickHouse, deployed to Google Cloud.

You’ll work directly with the founders, shaping data pipelines, APIs, and the UI with a strong emphasis on testing and observability.

Qualifications

• Strong experience with TypeScript, React, and Node.js.
• Relational databases design and querying (Postgres/Prisma).
• Experience building APIs (tRPC, REST, GraphQL) in a monorepo.
• Testing: Vitest, Playwright; code review practices.

Responsibilities

• Take features from problem definition to production with cross-functional scope.
• Design and improve data pipelines across Postgres, Elasticsearch, Redis, ClickHouse.
• Build and run services on Google Cloud and keep them observable with monitoring and dashboards.
• Contribute to coding standards, testing, and technical direction.

Skills

TypeScript

React

Node.js

Postgres

Fastify

Prisma

Google Cloud

Elasticsearch

Tools

Prisma

Postgres

Elasticsearch

Redis

Job description

We're looking for a Senior Full Stack Developer to join our tech team.

About the job

Promptwatch shows businesses how they appear in AI-generated answers. We track citations, sentiment, and visibility across every major AI engine, and we process billions of crawler logs and AI responses in real time. Thousands of companies use the product to make decisions every day.

The role

In this role you own features from start to finish. You scope them with product and design, build the schema and the API, ship the UI, and keep an eye on them in production. You work directly with the founders, with no management layers between you and the decisions.

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

• 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

Nice to have

• Elasticsearch, ClickHouse, or other analytical datastores
• Working with LLM APIs (OpenAI, Anthropic, Google)
• Data visualization (Recharts, D3, or similar)
• Monorepo tooling (Turborepo, pnpm workspaces)
• Google Cloud Platform

How you work

• Clear communication
• Curiosity over credentials
• Active in software communities

What we offer

• Base salary: €90,000 - €120,000
• A real say in product and technical direction
• A well-maintained codebase: strict TypeScript, Biome linting, thorough types
• Time and budget for learning: conferences, courses, books
• An office in central Amsterdam, with a hybrid setup where you manage your own schedule
• Regular team off-sites and company sports activities

Promptwatch helps brands understand and improve how they show up in AI search across platforms like ChatGPT, Claude, Gemini, and Perplexity.

Founded in Amsterdam in 2025, we’ve grown quickly, raised €7.2M in funding, and now serve 1,800+ organizations. We’re building the infrastructure for the shift from traditional search to AI-native discovery.