Senior Ruby Engineer

MILE; Sheffield; On-site; GBP 90,000 - 140,000; Full time

Job summary

MILE is seeking an experienced backend engineer to design and implement scalable Ruby-based systems powering our luxury fashion e-commerce platform. You will build APIs, manage data parity with partners, and own services end-to-end from design through deployment and monitoring.

We value deep Ruby DSL expertise, PostgreSQL mastery, and strong cloud/container skills (AWS, Docker, Kubernetes). Leadership and collaboration are essential in our fast-growing environment.

Qualifications

• 8+ years building and scaling backend systems in production.
• Expert Ruby, Rails AREL, and impenetrable metaprogramming skills.
• Strong API design skills for GraphQL and REST services.
• Deep PostgreSQL data modeling and performance tuning.
• Experience with distributed microservices and multi-tenant architectures.
• Proficient with cloud infra (AWS) and containerization (Docker/Kubernetes).
• Leadership experience and ability to mentor junior engineers.

Responsibilities

• Design scalable, high-performance backend systems for e-commerce.
• Build interfaces for frontend, mobile, and third-party integrations.
• Define data parity models with third parties, ensuring consistency.
• Architect systems for membership, catalog, checkout, orders, and payments.
• Collaborate cross-functionally and drive feature delivery.
• Own services end-to-end from design to deployment and monitoring.
• Promote code quality, testing, reliability, and observability.
• Contribute to backend architecture decisions at scale.
• Mentor engineers and foster technical excellence.

Skills

Ruby expert

Rails AREL

Metaprogramming

DSLs

PostgreSQL

API design

GraphQL & REST

Distributed systems

Microservices

AWS / ECS / CodeBuild

Docker / Kubernetes

Testing & observability

Mentoring

Tools

Docker

Kubernetes

AWS

CodeBuild

Job description

• Design and implement scalable, high-performance backend systems to power our e-commerce experience
• Build and maintain interfaces that support our frontend, mobile, and third-party integrations
• Be very experienced working with pull, push models for data parity between third parties and our systems around e-commerce concerns of product, stock, orders and fulfillment synchronization
• You'll design, implement and deploy reliable software to solve complex e-commerce concerns
• Architect systems for membership access, catalog management, checkout, order fulfillment, and payments
• Collaborate cross-functionally with product, design, and data teams to deliver features that elevate the user experience
• Own backend services end-to-end, from design to deployment and monitoring
• Contribute to best practices in code quality, testing, reliability, and observability
• Help define our backend architecture and make strategic technical decisions as we scale
• Mentor junior engineers and foster a culture of technical excellence and collaboration
  

What You'll Do

• Design and implement scalable, high-performance backend systems to power our e-commerce experience
• Build and maintain interfaces that support our frontend, mobile, and third-party integrations
• • Be very experienced working with pull, push models for data parity between third parties and our systems around e-commerce concerns of product, stock, orders and fulfillment synchronization
  • You'll design, implement and deploy reliable software to solve complex e-commerce concerns
• Architect systems for membership access, catalog management, checkout, order fulfillment, and payments
• Collaborate cross-functionally with product, design, and data teams to deliver features that elevate the user experience
• Own backend services end-to-end, from design to deployment and monitoring
• Contribute to best practices in code quality, testing, reliability, and observability
• Help define our backend architecture and make strategic technical decisions as we scale
• Mentor junior engineers and foster a culture of technical excellence and collaboration
  

Who You Are

• 8+ years of experience building and scaling backend systems in production environments
• 4+ years leading Ruby cloud stack teams as a Principal Engineer/Architect
• You are very familiar with the Ruby object model - eigenclasses, method dispatch, method_missing, send, and all variable types
• Expert skills with Ruby idiomatic patterns, terse styling, metaprogramming and be able to create macros, DSLs, etc
• • Have experience contributing to wildly used gems or developed internal DSLs for domain specific needs
• Ruby without Rails - you are able to develop complex applications and deploy Rails features vs custom Ruby plugins for the right use cases
• Proficiency in building APIs and distributed services using Ruby
• Must know the full ins/outs of Rails AREL, performant code, and proper Sidekiq job handling
• Have expert knowledge of proper data model design for e-commerce concerns and understand how to handle locking sensitive resources such as a credit card charge and concepts such as state machines
• Expert experience with PostgreSQL, including complex joins and reporting queries, and familiarity with data modeling and performance optimization
• Familiarity with cloud infrastructure (e.g., AWS, ECS, CodeBuild) and containerization (Docker,)
• Strong understanding of system design, data structures, and algorithmic principles
• Comfortable working in high-growth, early-stage environments—bias toward action and strong product sense are key
• A collaborative teammate who communicates clearly and is excited to shape the future of a luxury tech brand
  

Bonus Points

• Prior experience in e-commerce, marketplaces, or membership-based platforms
• Familiarity with event-driven architectures and message queues (Kafka, SQS, etc)
• Experience working closely with design or product teams in consumer-facing companies
• Passion for fashion, luxury, or retail innovation
  

Requirements

What You'll Do

• Design and implement scalable, high-performance backend systems to power our e-commerce experience
• Build and maintain APIs that support our frontend, mobile, and third-party integrations
• Architect systems for membership access, catalog management, checkout, order fulfillment, and payments
• Collaborate cross-functionally with product, design, and data teams to deliver features that elevate the user experience
• Own backend services end-to-end, from design to deployment and monitoring
• Contribute to best practices in code quality, testing, reliability, and observability
• Help define our backend architecture and make strategic technical decisions as we scale
• Mentor junior engineers and foster a culture of technical excellence and collaboration
  

Who You Are

• 7+ years of experience building and scaling backend systems in production environments
• Genuine Rubyist having written custom DSLs and/or contributed to a major Ruby gem with the deepest knowledge of how to utilize Ruby's metaprogramming capabilities for maximal terse and DSL-centric applications
• Experience with the specific challenges of concurrency, inventory management/reservation, currency/price management, and third party API integration system designs - push, pull, effective normalization, etc
• High familiarity with excellent microservices software design - using software DSLs over cloud deployed solutions - across dozens of models, concerns, and integrations
• Experience with relational databases (e.g., PostgreSQL) and familiarity with data modeling and performance optimization
• Familiarity with cloud infrastructure (e.g., AWS) and containerization (Docker, Kubernetes)
• Experience developing and deploying GraphQL and RESTful API interfaces
• Experience developing multi tenant systems, relating to concerns of access control, reporting, and authorization/authentication
• Strong understanding of system design, data structures, and algorithmic principles
• Comfortable working in high-growth, early-stage environments—bias toward action and strong product sense are key
• A collaborative teammate who communicates clearly and is excited to shape the future of a luxury tech brand
  

Bonus Points

• Prior experience in e-commerce, marketplaces, or membership-based platforms
• Familiarity with event-driven architectures and message queues (Kafka, SQS, etc)
• Experience working closely with design or product teams in consumer-facing companies
• Passion for fashion, luxury, or retail innovation
  

Benefits

Why Join MILE

• Opportunity to play a key role in shaping the future of the company
• Collaborative and innovative work environment
• Career growth opportunities in a fast-growing organisation
  

Let's build something people talk about. Together.