Berlin, Berlin, Germany Hybrid Employment

Castle Tech GmbH is hiring a Frontend Engineer

About the Role

CarOnSale is looking for a Senior Frontend Engineer to build a new standalone product from the ground up. This is a high-impact position where you will influence system design, architecture, and product direction from day one, turning ideas into production-ready software.

What You'll Do

  • Build a new production-grade product from the ground up.
  • Design and implement a scalable frontend architecture using Angular and TypeScript.
  • Take ownership of features from concept to deployment.
  • Collaborate closely with product managers, designers, and backend engineers.
  • Contribute to technical architecture and system design decisions.
  • Help establish development standards, CI/CD pipelines, and engineering best practices.
  • Mentor other engineers through code reviews and technical feedback.
  • Continuously improve development workflows using modern tools and AI-assisted engineering.
  • Design systems with clear component boundaries and scalability in mind.
  • Identify technical risks and propose practical solutions.
  • Help improve the team’s engineering standards and productivity.
  • Deliver high-impact features that support business and product goals.

What We're Looking For

  • 5+ years of experience as a frontend engineer.
  • Strong expertise with Angular (v11+) and TypeScript.
  • Experience designing scalable frontend architectures.
  • Strong understanding of software design principles and maintainable systems.
  • Experience with modern frontend tooling (NPM, Webpack or esbuild).
  • Experience working with Git, CI/CD pipelines, and Docker.
  • Experience working in agile teams (Scrum or Kanban).
  • Strong communication skills in English.

Nice to Have

  • Experience with frontend testing frameworks (Jest, Cypress, Playwright).
  • Experience building greenfield products or new platforms.
  • Familiarity with AI-related components such as RAG or vector databases.
  • Experience with Material Design or product-oriented UI development.
  • Conversational German.

Technical Stack

  • Angular, TypeScript, NPM, Webpack, esbuild, Git, Docker, Jest, Cypress, Playwright

Team & Environment

You will collaborate closely with product managers, designers, and backend engineers. AI is part of how we work, and we expect engineers to actively use modern AI tooling to improve productivity and quality. You'll join a collaborative team of ambitious engineers who enjoy building great products.

Benefits & Compensation

  • Build something new – work on a greenfield product from the start.
  • Real technical ownership – influence architecture and system design.
  • Modern engineering environment – use the latest tools and workflows.
  • Flexible hybrid work – office and remote options in Berlin or Munich.
  • Your gear, your choice – MacBook or Windows setup with the tools you need.
  • Growth and development – structured onboarding, feedback cycles, and coaching.

Work Mode

This is a hybrid position based in our Berlin or Munich offices.

CarOnSale is an equal opportunity employer.

Required Skills
AngularTypeScriptNPMWebpackesbuildGitDockerJestCypressPlaywrightFrontend ArchitectureSoftware Design
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About company
Job Details
Department Software Development
Category frontend
Posted 14 days ago