46 Site Reliability Engineer jobs in the United Kingdom

Site Reliability Engineer | £65,000–£5,000 DOE | Hybrid (Bristol-based, occasional site visits)
Clearance: Must be eligible for DV Clearance

Founded in 2019 by engineers solving complex cross-domain problems for government organisations, TwinStream delivers technical excellence and exceptional service to high-profile clients. Our teams work both on-site and remotely, supporting mission-critical systems where performance and reliability are paramount.

The Site Reliability Engineer Role:

We are seeking a Site Reliability Engineer (SRE) to ensure the availability, performance, and cost-effectiveness of our cloud and on-prem services. You will collaborate with software engineers and system administrators to improve observability, reduce downtime, and proactively mitigate reliability risks across a growing portfolio of services.

Key Responsibilities of the Site Reliability Engineer:

• Improve reliability and performance across multiple subsystems.
• Automate manual tasks and eliminate unnecessary alerts.
• Enhance monitoring capabilities to identify and resolve issues before they impact users.
• Support and optimise CI/CD pipelines and cloud infrastructure.
• Research and evaluate new tools to influence build-vs-buy decisions.
• Contribute to technical innovation across diverse stacks and environments.

What We’re Looking For:

• Experience with configuration management tools (e.g., Ansible, Chef).
• Proficiency with Terraform, Docker, and container orchestration (Kubernetes, OpenShift, or similar).
• Hands-on experience with CI/CD tools (Jenkins or equivalent).
• Knowledge of monitoring solutions (Prometheus, Grafana, InfluxDB).
• Familiarity with MQ messaging (RabbitMQ or similar).
• Linux administration, scripting, and network security protocols.
• Experience with cloud services (preferably AWS – EC2, RDS, S3, Lambda).

Desirable: Experience coding in Java, Go, or Python; cross-domain technologies; observability patterns; and service management environments.

Why Join TwinStream?

• Salary: £65, 0–£9 000 (DOE & clearance level)
• Pension: 8% employer contribution
• Private Healthcare: Includes dental & optical cover for you & your family
• Learning & Development: ,000 annual training budget
• Flexible Working: Hybrid & family-friendly culture
• Additional Perks: EV leasing scheme, 25 days’ holiday + bank holidays, life assurance, cycle-to-work scheme, and team events

Ready to Shape the Future of Mission-Critical Systems?

Apply now and join a team where innovation, reliability, and technical excellence drive everything we do.

WHJS1_UKTJ

Site Reliability Engineer | £65,000–£95,000 DOE | Hybrid (Bristol-based, occasional site visits)
Clearance: Must be eligible for DV Clearance

Founded in 2019 by engineers solving complex cross-domain problems for government organisations, TwinStream delivers technical excellence and exceptional service to high-profile clients. Our teams work both on-site and remotely, supporting mission-critical sy.

WHJS1_UKTJ

About Us

Commify has transformed over the last decade under Private Equity ownership, operating in 9 countries including the UK, France, Spain, Italy, Romania, Germany, Netherlands, Australia, and the USA. Our mission is to make business communication brilliant through our extensive range of products that include SMS, WhatsApp, Email, and more. Serving over 70,000 businesses worldwide, we send more than 5 billion communications annually.

As we look to expand our impressive product portfolio, we recognize that our greatest asset is our people. Join us and be part of our success story!

Role Summary

In the role of Site Reliability Engineer at Commify, you will be an integral part of our SRE team. Your focus will be on ensuring that our products and platforms perform at their best, understanding how our software interacts with both physical and Cloud infrastructure to deliver exceptional messaging solutions.

Key responsibilities include:

• Maintaining high levels of system performance through monitoring and performance tuning
• Implementing scalability and fault tolerance
• Automating processes and improving operational efficiencies
• Troubleshooting application and middleware challenges
• Collaborating with engineering teams to support high-throughput production environments
• Building and maintaining robust deployment pipelines

Requirements

What essentials are we looking for?

• Proficiency with Microsoft Azure
• Strong expertise in Terraform, App Services, and Kubernetes
• Fluent in both written and spoken English
• A genuine passion for reliability in systems
• Experience in creating and modifying Terraform deployments
• Prior experience in an operations role, ideally as a Site Reliability Engineer
• Ability to work cross-functionally, take ownership of tasks, and prioritize effectively
• Excellent communication and collaboration skills
• Experience with monitoring solutions (e.g., Datadog, Azure Application Insights, Log Analytics)
• Programming/scripting skills for automation (favoring PowerShell, but also comfortable with Bash, C#, Ruby, or Python)
• Experience with web-based applications

It's desirable for you to have:

• Familiarity with Azure DevOps pipelines
• Experience with Microsoft Server Operating Systems
• Understanding of service level objectives and operational requirements for cloud-based solutions
• Comprehensive knowledge of Microsoft Azure Cloud offerings (especially in PaaS)
• Experience with tools such as Terraform, Ansible, VSTS, ARM, Puppet, Chef, Jenkins, ELK, and Grafana
• Understanding of DNS, Load Balancer configuration, Active Directory, and network infrastructure in the cloud
• Experience in agile environments and methodologies including TDD, Scrum, or Kanban
• Knowledge of monitoring and alerting systems for microservice architectures
• Applied knowledge of cloud security best practices

Benefits

• Competitive Salary (£65 - 75,000)

• Company bonus scheme
• Comprehensive healthcare cash plan
• A generous 27 days of annual leave in addition to Bank Holidays
• 2 Wellbeing leave days and 2 days dedicated to giving back to your community
• Enjoy your birthday off!
• Employer pension contribution at 5%
• Death in service benefit (4 times your salary)
• Annual award recognition
• Fun monthly and quarterly social events
• Opportunities for training and professional development
• Flexible hybrid working arrangements

ABOUT THE COMPANY

Infleqtion is a global quantum technology company solving the world’s most challenging problems. The company harnesses quantum mechanics to build and integrate quantum computers, sensors, and networks. From fundamental physics to leading edge commercial products, Infleqtion enables “quantum everywhere” through our ecosystem of devices and platforms. We are recruiting for a Site Reliability Engineer with DevOps skills for our quantum computing platform.   

LOCATION

Infleqtion has offices in the USA, United Kingdom and Australia. This is a full-time position split between our Kidlington, Oxford office and the National Quantum Computing Centre, Harwell. Our flexible working policy enables all full-time employees to work up to 2 days a week from home if work permits.  Candidate will need to be able to travel independently to these locations, as required. 

POSITION SUMMARY

As part of our strategy for growth at Infleqtion UK, we are expanding our engineering team and recruiting a Site Reliability Engineer with DevOps skills. 

For this role, you will bring a mix of technical skills, problem-solving ability and effective communication, playing a pivotal role in operational reliability and code velocity for our quantum research and device development. 

This role involves a combination of network management, server administration, and proactive involvement in our continuous integration and deployment processes. The successful candidate will ideally possess a solid technical background in both systems engineering and software development. 

JOB RESPONSIBILITIES

• Network Management: Design, implement, and manage robust networks, including configuring switches and managing network-connected devices. 

• Software Deployment: Manage Docker containers and orchestrate CI/CD pipelines for efficient software deployment and updates. 

• Infrastructure as code: Design, develop, and maintain IaC solutions and implement CI/CD pipelines to automate deployment processes. 

• Collaboration and Documentation: Collaborate with both software developers and hardware engineers in a lab environment, documenting processes and system configurations for ongoing projects. 

• Developing Standard Operating Procedures: Working with a variety of users and software engineers to implement and develop standard operating procedures for software deployments and system parameter updates. 

• Proactive Problem-Solving Skills:  Integrating complex systems that include embedded boards, computer systems, and hardware interfaces. Your role will focus on seamlessly coordinating these components to ensure the system is consistently operational and optimised. 

• 'System-down' planning and response. Own system management and coordinate response to efficiently maintain high up-times. Plan and implement system backup policies to ensure swift recovery. 

Requirements

• Excellent understanding of networking technologies, connecting computers and embedded devices 

• Proficiency with: 

• Deployment and configuration management framework e.g. Ansible 

• Linux systems 

• Bash scripting 

• Docker and/or Kubernetes 

• Git and version control-centric workflows 

• Good collaboration skills, able to work in a team environment where engagement and participation are an expected part of successful job performance. 

Experience 

• A minimum of 2 years’ experience working in related engineering field. 

• Proven experience working with complex systems consisting of a number of networked nodes, and including embedded systems (such as raspberry Pi, IoT devices). 

• Professional-level verbal and written communication skills, able to effectively share information with technical and non-technical staff. 

Qualifications: 

• Bachelor’s degree in computer science, engineering, or other related field, (or equivalent), or extensive experience. 

• Baseline Personnel Security Standard (BPSS) required (we will arrange for successful candidate). 

Desirable: 

• Experience with ARTIQ systems, or controlling hardware via python API. 

• Experience working with production grade systems. 

• Python, developing & maintaining code, managing packages and dependencies. 

• A background/interest in Quantum Physics/Quantum computing. 

Benefits

In addition to your base compensation, we offer a generous Total Rewards program which includes: 

• Competitive salary 

• Unlimited PTO 

• Generous company pension contribution 

• Cycle to work and Technology schemes 

• BUPA medical insurance upon successful completion of probationary period 

• Incentive Stock Option Plan 

Gizmo is an AI startup on a mission to make learning so easy that anyone can learn anything. We're building Duolingo for anything - a platform that uses gamification and social mechanics to make learning fun.  

With over 1 million monthly active users and $4M in annual recurring revenue, we’re already one of the fastest-growing startups in the UK. Backed by leading investors, we recently raised $22M in Series A funding to accelerate our vision of helping 1 billion people learn.

Role Overview
Reporting to the CTO, you will own capacity, performance and reliability for Gizmo’s full-stack platform as daily traffic climbs from hundreds of thousands to millions of users. You’ll write code across the stack, but your charter is classic SRE: defend SLOs , eliminate toil , and raise the ceiling on scale before it becomes a hard limit.

Key Responsibilities

• Define SLIs/SLOs for latency, availability and error rate; codify error budgets and partner with product teams on trade-offs.
• Perform load-testing, capacity modelling and up-front scalability design for PostgreSQL, OpenSearch, Redis, Hasura and CF Workers; produce data-driven scaling plans.
• Extend metrics, structured logging and tracing; establish alert rules that page only on user-visible impact; build actionable runbooks .
• Join the on-call rotation, lead blameless post-mortems, drive remediation work to closure and track MTTR/MTBF improvements.
• Automate repetitive ops on Kubernetes and CI/CD; keep “toil” <50 % of your time by pushing fixes into code.
• Coach full-stack engineers on query optimisation, schema design and back-pressure techniques; document patterns and anti-patterns by creating an SRE playbook

Requirements

• Hands-on scale experience : you have run relational stores at 100 k+ TPS or 1 M+ concurrent users (e.g., multi-tenant PostgreSQL, sharded MySQL).
• Strong backend fundamentals around concurrency, caching, indexing and distributed systems trade-offs.
• Proven track record of setting SLOs, building dashboards (Prometheus/Grafana, OpenTelemetry, etc.) and tuning alerts.
• Comfort with Kubernetes , IaC and cloud-native patterns; can debug from network to application layer.
• Start-up bias for action: you prioritise high-leverage fixes, ship iteratively and own outcomes end-to-end.
• Collaborative and feedback-driven; you welcome post-mortem culture and continuous improvement.
• Driven by impact - you prioritise work that moves the needle!

Nice-to-haves: experience with Hasura internals, Cloudflare Workers edge optimisation, or operating OpenSearch at scale.

Benefits

• Highly competitive salary.
• You'll own a piece of what you're building - equity included.
• Hybrid working model with 4 days in our East London office, ideally located between Shoreditch High Street, Old Street, and Liverpool Street stations.
• The opportunity to become one of the earliest employees in one of the UK’s fastest-growing startups.
• Private health insurance