Senior Backend Engineer – Ruby on Rails

Gravitas Recruitment Group (Global) Ltd; Greater London; Hybrid; GBP 90,000 - 100,000; Full time

Benefits offered by this job

30 days leave

Learning budget £1k

Private medical insurance

Pension match 6%

MacBook Pro

Flexible hybrid

Job summary

Gravitas Recruitment Group (Global) Ltd is seeking a Senior Backend Engineer in London. This hands-on IC role focuses on owning complex backend problems, shaping technical direction and elevating the engineering team while staying close to the code.

You will work with Ruby on Rails at the core, scale Rails apps, design robust APIs, and collaborate with Product to maximise customer impact. Hybrid work includes 1 day in the office and 4 days remote.

Qualifications

• Strong commercial experience building production systems with Ruby on Rails.
• Experience designing and scaling APIs and backend services.
• Strong testing practices and knowledge of RSpec.
• Understanding of architecture, scalability and maintainable software design.
• Experience taking meaningful technical ownership and collaborating with Product.

Responsibilities

• Build and scale production Ruby on Rails applications.
• Evolve and improve an established Rails codebase.
• Design and maintain robust internal and external APIs.
• Work with PostgreSQL including data modelling and performance tuning.
• Utilise Sidekiq for background processing and improve testing standards.
• Make pragmatic architectural decisions for long-term maintainability.
• Collaborate with Product to understand customer impact and own problems end-to-end.
• Pair, mentor and share knowledge across the engineering team.

Skills

Ruby on Rails

PostgreSQL

API design

RSpec

Testing practices

Ownership

Mentoring

Collaboration

Tools

React

Next.js

TypeScript

Redis

AWS

Job description

£90,000 – £100,000 | London | Hybrid – 1 day in office / 4 days from home

We’re partnering with a fast-growing, product-led technology business to hire a Senior Backend Engineer into a high-performing engineering team.

This is a genuinely hands-on Senior IC role. It isn’t a Team Lead position and there’s no expectation to move away from coding. Instead, we’re looking for an experienced engineer who can take ownership of complex backend problems, influence technical direction and make the engineers around them better.

The business is continuing to scale its core platform, with Ruby on Rails sitting at the heart of the backend. As the product and customer base have grown, so have the engineering challenges around architecture, scalability, maintainability and where business logic should live.

You’ll work on challenges including:

• Building and scaling production Ruby on Rails applications
• Evolving and improving an established Rails codebase
• Designing and maintaining robust internal and external APIs
• Working extensively with PostgreSQL, including data modelling, queries and performance
• Background processing using Sidekiq
• Improving testing, reliability and overall engineering standards
• Making pragmatic architectural decisions with long-term maintainability in mind
• Working closely with Product to understand the customer impact behind technical decisions
• Owning problems end-to-end rather than simply completing tickets
• Pairing, mentoring and sharing knowledge across the engineering team

The wider environment also includes React / Next.js / TypeScript, Redis and AWS, so engineers who are comfortable occasionally moving beyond the backend will have plenty of opportunity to do so.

What we're looking for

You’ll have strong commercial experience building production systems with Ruby and Ruby on Rails, but this isn't simply about counting years on a CV.

We’re particularly interested in engineers who can demonstrate:

• Good PostgreSQL and SQL knowledge
• Experience designing and scaling APIs and backend services
• Strong testing practices, ideally including RSpec
• An understanding of architecture, scalability and maintainable software design
• Experience taking meaningful technical ownership
• Strong collaboration with Product and other engineers
• A pragmatic approach to solving problems rather than over-engineering them

Just as importantly, we’re looking for a low-ego force multiplier.

That could mean improving engineering practices, mentoring through pairing, de-siloing knowledge, improving code-review culture, introducing better testing or simply helping the people around you become stronger engineers.

You don't need a Lead title to demonstrate leadership.

Location: Central London

Hybrid: 1 day per week in the office / 4 days working from home

Benefits include:

• 30 days' annual leave + bank holidays
• £1,000 annual learning & development budget
• Private medical insurance
• Pension contribution matched up to 6%
• MacBook Pro
• Highly flexible hybrid working

The process is designed to assess both technical ability and how you work with other engineers:

The technical stages are as much about how you think, the decisions you make and the trade-offs you consider as simply reaching the correct answer.

If you're an experienced Ruby engineer who wants to remain close to the code, solve meaningful scaling problems and have genuine influence over both the product and engineering culture, I'd love to hear from you.