Backend Engineer (Ruby on Rails) for Sustainable E-commerce Marketplace

OpportuLand; Deutschland; Remote; EUR 70,000 - 90,000; Full time

Benefits offered by this job

Free Udemy access

Job summary

OpportuLand is seeking an experienced Backend Engineer (Ruby on Rails) to help modernize a European e-commerce marketplace focused on sustainable fashion and responsible retail. You will help decompose a Rails monolith into domain-oriented services, design APIs, and work with SRE, product, and frontend teams on scalable backend solutions.

You will contribute to an event-driven architecture, database optimization, and the use of AI-powered development tools to improve code quality and workflows.

Qualifications

• Several years of backend development experience, preferably with Ruby on Rails
• Strong experience designing and building REST and/or GraphQL APIs
• Solid SQL and relational database knowledge including schema design, migrations, and query optimization
• Understanding of backend architecture, domain-driven design, and service-oriented systems
• Experience with automated testing, preferably RSpec
• Basic experience with Docker and CI/CD pipelines
• Ability to make pragmatic engineering decisions and work in a cross-functional product team
• Experience using AI-powered development tools in daily workflows
• Good written and spoken English and/or German

Responsibilities

• Develop and maintain backend services and APIs for the marketplace (REST and GraphQL)
• Contribute to decomposition of the Rails monolith into domain-oriented services
• Design internal service communication using gRPC and Protocol Buffers
• Work with relational databases including schema design, migrations, and query optimization
• Implement event-driven processes and cloud messaging integrations
• Write automated tests, participate in code reviews, maintain high engineering quality
• Collaborate with frontend, product, and SRE teams on APIs and deployments
• Leverage modern AI tools to improve coding, testing, and reviews

Skills

Ruby on Rails

REST APIs

GraphQL APIs

SQL & DB design

Domain-driven design

Automated testing (RSpec)

English/German communication

Cross-functional collaboration

AI-powered development tools

Tools

Docker

CI/CD

gRPC

Kubernetes

Terraform

JWT/JWKS

Job description

Backend Engineer (Ruby on Rails) for Sustainable E-commerce Marketplace

We are looking for an experienced Backend Engineer to join the development of a mature European e-commerce marketplace focused on sustainable fashion, lifestyle products, and responsible retail.The platform connects consumers with eco-conscious brands and merchants across multiple product categories and has been evolving for more than a decade.The engineering team is actively modernizing the existing architecture while continuing to develop the product. One of the key technical initiatives is the gradual decomposition of a Ruby on Rails monolith into independent, domain-oriented services using the Strangler Fig pattern.The role combines backend product development, API design, database work, event-driven architecture, and close collaboration with frontend, product, and SRE teams.The team values pragmatic engineering, strong product ownership, sustainable code quality, automated testing, and practical use of modern AI development tools.

Benefits

• Fully remote work
• Free access to Udemy courses across 1,000+ topics for professional and personal development
• Long-term collaboration on a mature European e-commerce product
• Direct involvement in a major platform modernization and architectural transformation
• Collaboration with an experienced international engineering team
• Opportunity to influence technical decisions and system architecture
• High level of ownership and involvement in technical decision-making

Requirements

• Several years of professional backend development experience, preferably with Ruby on Rails
• Strong experience designing and building REST and/or GraphQL APIs
• Solid SQL and relational database knowledge, including schema design, migrations, and query optimization
• Understanding of backend architecture, domain-driven design, and service-oriented systems
• Experience with automated testing, preferably RSpec, and a strong focus on code quality
• Basic experience with Docker and CI/CD pipelines
• Ability to make pragmatic engineering decisions and work effectively in a cross-functional product team
• Experience using AI-powered development tools in daily engineering workflows
• Good written and spoken English and/or German

Will be a plus

• Experience with gRPC and Protocol Buffers
• Experience with event-driven architectures or messaging systems such as Google Cloud Pub/Sub
• Experience with Kubernetes, Helm, Terraform, or Terragrunt
• Experience with API gateways and JWT/JWKS-based authentication
• Experience migrating monolithic applications toward service-oriented architectures
• Experience with high-traffic e-commerce or marketplace platforms

Responsibilities

• Develop and maintain backend services and APIs for the marketplace, including REST and GraphQL
• Contribute to the gradual decomposition of the existing Rails monolith into domain-oriented services
• Design internal service communication using gRPC and Protocol Buffers
• Work with relational databases, including schema design, migrations, and query optimization
• Implement event-driven processes and integrations using cloud messaging technologies
• Write automated tests, participate in code reviews, and maintain high engineering quality standards
• Collaborate closely with frontend, product, and SRE teams on APIs, architecture, and deployments
• Use modern AI development tools to improve coding, testing, and review workflows

About client

Germany’s leading online marketplace for sustainable fashion and green lifestyle products. It connects conscious consumers with vetted brands and sellers offering eco-friendly alternatives across fashion, home, beauty, and daily essentials. Its model combines curated assortment, sustainability standards, and a strong marketplace experience for both shoppers and merchants.

Location

Germany