Senior Ruby On Rails Engineer

Senior Ruby On Rails Engineer / Tech Lead

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

Salary: Up to £100,000 (DOE)

The opportunity:

We’re looking for a Senior Ruby Engineer / Tech Lead to join a growing technology business building large-scale operational SaaS platforms used within complex, real-world environments.

This is a hands-on senior engineering role with a clear pathway into broader technical leadership responsibilities. It would suit someone who enjoys solving complex backend challenges while also taking ownership of delivery, technical direction, and team support.

You’ll play a key role in scaling a modern Rails-based platform that supports high-volume transactional workflows, integrations with external systems, and mission-critical operational processes.

Working closely with the Director of Engineering, you’ll help shape backend architecture, improve delivery processes, support customer onboarding initiatives, and act as a senior technical escalation point across the platform.

The business operates within a fast-paced product environment where reliability, scalability, and delivery quality are critical. The culture is collaborative, pragmatic, and ownership-driven, with a strong focus on autonomy, accountability, and continuous improvement.

What you’ll be doing:

As a Senior Ruby Engineer / Tech Lead, you’ll take ownership of backend delivery across key product areas while remaining heavily involved in hands-on engineering.

Key responsibilities include:

Leading backend development across a large-scale Rails application

Owning technical direction and contributing to architectural decisions

Designing, building, and maintaining scalable backend services and APIs

Supporting platform scalability, reliability, and maintainability

Improving and refactoring existing backend functionality to reduce technical debt

Optimising background job processing and asynchronous workflows

Supporting integrations with external third-party systems and APIs

Leading delivery planning, estimation, and technical scoping activities

Acting as a senior escalation point for technical and delivery-related challenges

Collaborating closely with product, engineering, and stakeholder teams

Supporting sprint planning, Agile ceremonies, and delivery processes

Mentoring and supporting engineers through technical guidance and collaboration

Helping improve engineering standards, processes, and team effectiveness

What we’re looking for:

Essential experience:

Strong commercial experience with Ruby on Rails within production environments

Experience building and maintaining scalable backend systems and APIs

Strong understanding of Rails monolith architecture

Experience with PostgreSQL, Redis, and Sidekiq

Experience working with AWS-based infrastructure

Experience using Docker within development or production environments

Strong debugging and problem-solving capabilities

Excellent communication and stakeholder management skills

Ability to explain technical concepts clearly to both technical and non-technical audiences

Strong ownership mentality with a pragmatic engineering approachDesirable / bonus experience:

Experience leading Agile ceremonies or delivery processes

Experience scoping technical work and contributing to estimation activities

Experience working with Kubernetes-based deployments

Experience integrating third-party platforms and APIs

Experience within B2B SaaS or operational platform environments

Experience supporting live production systems at scale

Experience mentoring or supporting engineers within a team environmentAbout you:

You’re a hands-on engineer who enjoys solving complex technical problems

You’re comfortable balancing technical leadership with day-to-day delivery

You enjoy mentoring and supporting other developers

You care about scalability, maintainability, and engineering quality

You communicate clearly and collaborate well across technical and non-technical teams

You’re proactive, adaptable, and comfortable taking ownership

You thrive in fast-moving environments where technology has real operational impact

Core technology stack:

Ruby

Ruby on Rails

PostgreSQL

Redis

Sidekiq

REST APIs

AWS

Docker

Kubernetes

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