Senior Ruby on Rails Backend Engineer — Hybrid London in City of Westminster

Senior Ruby on Rails Backend Engineer — Hybrid London in City of Westminster

City of Westminster Full-Time 65000 - 85000 £ / year (est.) Home office (partial)
Fynity

At a Glance

  • Tasks: Join a dynamic team to maintain and evolve backend systems for operational workflows.
  • Company: Innovative tech company in London with a hybrid work model.
  • Benefits: Competitive salary, flexible working, and opportunities for professional growth.
  • Other info: Fast-paced environment with a focus on reliability and collaboration.
  • Why this job: Tackle complex backend challenges and make a real impact on live production systems.
  • Qualifications: Strong Ruby on Rails experience and a passion for backend engineering.

The predicted salary is between 65000 - 85000 £ per year.

Location: London (Hybrid – 2 days per week onsite)

Salary: £65,000 to £85,000 (DOE)

The opportunity

We’re looking for a Mid / Senior Ruby Engineer to join a growing technology business building operational SaaS platforms used within large-scale, real-world environments. This role sits within a backend engineering team responsible for maintaining and evolving systems that support live operational workflows. You’ll work on modern Ruby on Rails applications that process high volumes of transactional activity, integrate with external systems, and support business‑critical operational processes. The environment is fast‑paced and product‑focused, with a strong emphasis on reliability, scalability, and engineering quality. You’ll work closely with Product, Platform, and Engineering teams to improve backend systems, strengthen operational stability, and support ongoing platform growth. This is a hands‑on engineering role with ownership across backend services, integrations, and production systems. It would suit someone who enjoys solving complex backend challenges, improving platform reliability, and working collaboratively across technical teams.

What you’ll be doing

  • Maintaining and improving Ruby on Rails applications supporting core operational processes
  • Designing, building, and maintaining scalable backend services and APIs
  • Writing clean, maintainable, and well‑tested code
  • Supporting platform reliability, scalability, and long‑term maintainability
  • Managing and improving integrations with third‑party systems and APIs
  • Optimising PostgreSQL database performance and background job processing
  • Supporting AWS‑based deployments and CI/CD processes alongside Platform teams
  • Investigating, troubleshooting, and resolving production issues
  • Improving monitoring, observability, and deployment confidence
  • Collaborating closely with frontend, mobile, and product teams
  • Contributing to backend architecture improvements and technical documentation
  • Supporting continuous improvement across engineering standards and delivery practices
  • Taking ownership of systems that directly support live operational environments

What we’re looking for

Essential experience
  • Strong commercial experience with Ruby on Rails within production environments
  • Strong understanding of object‑oriented programming and Rails architecture
  • Experience building and maintaining scalable backend systems and APIs
  • Strong PostgreSQL experience, including complex queries and performance optimisation
  • Experience with Redis and Sidekiq for background job processing
  • Experience working with REST APIs, JSON serialisation, and authentication methods such as JWT or SSO
  • Experience working with AWS‑based infrastructure
  • Experience using Docker within development or production environments
  • Experience troubleshooting and supporting live production systems
  • Strong debugging and problem‑solving capabilities
  • Experience working within existing codebases and improving legacy functionality
  • Strong communication and collaboration skills
  • Experience working within Agile environments using Git/GitHub
Desirable / bonus experience
  • Experience working with SOAP/XML integrations
  • Experience migrating serverless components into Rails applications
  • Familiarity with Vue.js
  • Experience supporting mobile applications or mobile‑focused backend services
  • Experience within regulated industries or operational B2B SaaS environments
  • Experience improving CI/CD pipelines and deployment reliability
  • Open‑source contributions or technical blogging experience

About you

  • You enjoy solving complex backend engineering challenges
  • You’re comfortable working across live production systems and operational platforms
  • You care about reliability, scalability, and maintainability
  • You take ownership and communicate proactively
  • You enjoy collaborating across engineering, product, and platform teams
  • You’re pragmatic, adaptable, and delivery‑focused
  • You thrive in fast‑moving environments where engineering quality matters

Core technology stack

  • Ruby
  • Ruby on Rails
  • PostgreSQL
  • Redis
  • Sidekiq
  • REST APIs
  • AWS
  • Docker
  • Git / GitHub
  • Vue.js (desirable)

Senior Ruby on Rails Backend Engineer — Hybrid London in City of Westminster employer: Fynity

Join a dynamic technology business in London as a Senior Ruby on Rails Backend Engineer, where you'll be part of a collaborative and fast-paced environment focused on building scalable SaaS platforms. With a strong emphasis on employee growth, you will have the opportunity to tackle complex backend challenges while enjoying a hybrid work model that promotes work-life balance. The company fosters a culture of innovation and continuous improvement, ensuring that your contributions directly impact operational success and platform reliability.

Fynity

Contact Details:

Fynity Recruitment Team

StudySmarter Expert Advice🤫

We think this is how you could land Senior Ruby on Rails Backend Engineer — Hybrid London in City of Westminster

Tip Number 1

Network like a pro! Reach out to your connections in the tech industry, especially those who work with Ruby on Rails. A friendly chat can lead to insider info about job openings or even referrals that could land you an interview.

Tip Number 2

Show off your skills! Create a GitHub profile showcasing your Ruby on Rails projects. Potential employers love to see real examples of your work, so make sure to highlight any complex backend challenges you've tackled.

Tip Number 3

Prepare for technical interviews by brushing up on your problem-solving skills. Practice coding challenges related to Ruby on Rails and backend systems. The more confident you are, the better you'll perform when it counts!

Tip Number 4

Don’t forget to apply through our website! We’re always on the lookout for talented engineers like you. Plus, applying directly can sometimes give you a leg up in the hiring process.

We think you need these skills to ace Senior Ruby on Rails Backend Engineer — Hybrid London in City of Westminster

Ruby on Rails
Object-Oriented Programming
Backend Systems Development
API Design and Maintenance
PostgreSQL Performance Optimisation
Redis
Sidekiq

Some tips for your application 🫡

Tailor Your CV:Make sure your CV highlights your Ruby on Rails experience and any relevant projects you've worked on. We want to see how your skills align with the role, so don’t be shy about showcasing your achievements!

Craft a Compelling Cover Letter:Your cover letter is your chance to tell us why you’re the perfect fit for this role. Share your passion for backend engineering and how you’ve tackled complex challenges in the past. Keep it engaging and personal!

Showcase Your Problem-Solving Skills:In your application, mention specific instances where you’ve solved tough backend issues or improved system performance. We love seeing how you think critically and approach challenges head-on!

Apply Through Our Website:We encourage you to apply directly through our website. It’s the best way for us to receive your application and ensures you’re considered for the role. Plus, it’s super easy!

How to prepare for a job interview at Fynity

Know Your Ruby on Rails Inside Out

Make sure you brush up on your Ruby on Rails knowledge before the interview. Be prepared to discuss your experience with building and maintaining scalable backend systems, as well as your understanding of Rails architecture. They’ll likely ask you about specific projects you've worked on, so have some examples ready that showcase your skills.

Showcase Your Problem-Solving Skills

Since this role involves troubleshooting live production systems, be ready to share how you've tackled complex backend challenges in the past. Think of specific instances where you identified a problem, implemented a solution, and improved system reliability or performance. This will demonstrate your hands-on experience and analytical thinking.

Familiarise Yourself with Their Tech Stack

Take some time to research the core technologies they use, such as PostgreSQL, Redis, and AWS. If you have experience with Docker or CI/CD processes, make sure to highlight that too. Showing that you understand their tech stack will help you stand out as a candidate who can hit the ground running.

Emphasise Collaboration and Communication

This role requires working closely with various teams, so it’s important to convey your collaboration skills. Prepare examples of how you've successfully worked with product, frontend, or platform teams in the past. Highlight your ability to communicate effectively and take ownership of projects, as these traits are crucial in a fast-paced environment.