Senior Ruby on Rails Developer

vor 1 Woche

Berlin, Berlin, Deutschland Mapp Digital Vollzeit 90.000 € - 120.000 € pro Jahr
Where You Can Make an Impact:

Interested in disrupting the trillion-euro retail industry? We're tackling one of the hottest and most challenging problems in the Fashion Universe: Building a recommendation system that understands individual style. By providing our customers with accurate product recommendations, we help reduce waste, optimize the supply chain and keep the return rate low, thus reducing the industry's environmental impact.

Our groundbreaking machine learning algorithms are wrapped in a Ruby backend, which is where you come into play. As part of the backend team you will be directly responsible for data preprocessing and recommendation serving.

Responsibilities Include:

We are looking for an experienced Ruby on Rails Engineer who's excited by the challenge of working on a mature system and helping shape its future. This role is a great fit for someone who enjoys untangling complex codebases, introducing best practices, and guiding a platform toward stability and growth. If you're a Rails expert who loves solving problems and building clarity where others see complexity, we'd love to hear from you

  • Explore and understand an existing Rails application and its business logic.
  • Fix critical bugs, refactor core components, and improve stability.
  • Add tests, CI/CD, and documentation to build long-term maintainability.
  • Collaborate with stakeholders to clarify requirements and priorities.
  • Contribute to building a healthy engineering culture and mentor future team members.
Skills and Experience Required:
  • 5+ years of professional experience with Ruby and Rails.
  • Proven ability to rescue or modernize existing systems.
  • Strong database and performance optimization skills.
  • Ability to work independently and bring structure to evolving requirements.
  • Comfortable in a fast-changing environment with shifting priorities.
  • Strong communication skills for explaining trade-offs to non-technical stakeholders.

       Nice to Have:

  • Cloud: AWS
  • Databases & Storage: Cassandra, Postgres, Elasticsearch
  • Streaming & Messaging: Kafka
  • Frontend development experience

You will join a dynamic and diverse team; we encourage candidates from diverse backgrounds to apply. Fully remote or hybrid work options are available depending on location. If you're a Ruby on Rails expert who loves solving problems and building clarity where others see complexity, we'd love to hear from you

About Mapp:

Mapp helps businesses boost customer engagement by combining AI-powered insights with cross-channel marketing automation. With over 20 years of experience and trusted by 700+ brands, Mapp empowers marketers to create personalized, data-driven campaigns across multiple channels. Our platform makes it easy to turn insights into actions, optimizing strategies, and delivering measurable results.


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