Site Reliability Engineer
| Posting date: | 04 September 2025 |
|---|---|
| Hours: | Full time |
| Closing date: | 04 October 2025 |
| Location: | Milton Keynes, Buckinghamshire |
| Remote working: | Hybrid - work remotely up to 3 days per week |
| Company: | CityFibre Holding Ltd |
| Job type: | Permanent |
| Job reference: | REF3714M |
Summary
This hybrid role offers a great balance of home and office working. You’ll join your colleagues in your local office at least 2 days a week.
Please note: There is an on-call rota and you will be required to support 24 x 7 callout cover
As the UK’s largest fibre-only network, and its only proven wholesale challenger, we’re busy setting new standards for what digital infrastructure can and should be.
Designed from scratch for the internet, our network is greener, more reliable and ready for the future. The products we provide over it not only lead the market on speed, value and service, they help businesses to innovate, provide entire communities with a better foundation for their digital lives and support economic growth, locally and nationally.
What does that mean for you? The opportunity to make internet connections (and daily life) a whole lot better, for a lot of people!
Joining us as a Site Reliability Engineer
As a Site Reliability Engineer, you’ll embed reliability into the design, build, and operation of CityFibre’s core platforms and services. You’ll be part of our Platform team, working alongside engineering squads to improve performance, automation, and service ownership. This role is key to helping our delivery teams release faster and operate with confidence. You’ll apply SRE principles to ensure our systems are reliable, scalable, and secure—supporting the technology that powers our business.
You’ll receive a competitive salary, a performance related bonus, and a range of benefits to support you across your financial, physical and mental wellbeing.
This is some of what you can expect to be doing:
Design for reliability and scalability from the outset
Implement monitoring, logging, and alerting systems
Automate deployments and operational tasks
Lead incident response and post-incident reviews
Define and maintain service level objectives (SLOs)
Support disaster recovery and resilience testing
What you’ll bring to the role
You’ll be a cloud-savvy engineer with a passion for automation and reliability. You’ll also have:
Experience with AWS and infrastructure as code
Familiarity with CI/CD pipelines and observability tools
Understanding of agile methodologies and event-driven architecture
PHP or Python development experience
Willingness to support 24x7 callout cover
Diversity, Inclusion & Belonging
We’re a Times Top 50 Employer for Gender Equality. We’re endorsed by WORK180 and we’re a partner of Diversifying. We have pledged our commitment to the Armed Forces Gold Covenant, are a Care Leaver Friendly Employer, and we’re a Disability Confident Leader. Working together with our Employee Communities, we’re wholly committed to ensuring that our people’s voices are heard, and that everyone feels a sense of belonging and pride to be a part of CityFibre. If you’d like to explore our culture and values, check out The CityFibre Way.
What you can expect from us
We want to offer you all the support you need to thrive inside and outside of work. This means giving you the tools to grow your career with us, as well as a comprehensive benefits package that you can adapt to your lifestyle. This includes 25 days annual leave, a day off on your birthday, a day off to support a charity or organisation of choice, a range of wellbeing and savings initiatives including private medical insurance, and supportive family friendly and menopause policies.
Qualifications
-
Additional information
We want to create a sense of belonging for everyone. We celebrate our differences and work to ensure everyone has the best chance to succeed, starting with our recruitment process. No matter your background, family or carer status, ethnicity, sexual orientation, religion, age, disability, gender, or gender identity, we welcome your application. If you need any support or reasonable adjustments throughout the application process, please email us at careers@cityfibre.com. We want to help!
Please note: There is an on-call rota and you will be required to support 24 x 7 callout cover
As the UK’s largest fibre-only network, and its only proven wholesale challenger, we’re busy setting new standards for what digital infrastructure can and should be.
Designed from scratch for the internet, our network is greener, more reliable and ready for the future. The products we provide over it not only lead the market on speed, value and service, they help businesses to innovate, provide entire communities with a better foundation for their digital lives and support economic growth, locally and nationally.
What does that mean for you? The opportunity to make internet connections (and daily life) a whole lot better, for a lot of people!
Joining us as a Site Reliability Engineer
As a Site Reliability Engineer, you’ll embed reliability into the design, build, and operation of CityFibre’s core platforms and services. You’ll be part of our Platform team, working alongside engineering squads to improve performance, automation, and service ownership. This role is key to helping our delivery teams release faster and operate with confidence. You’ll apply SRE principles to ensure our systems are reliable, scalable, and secure—supporting the technology that powers our business.
You’ll receive a competitive salary, a performance related bonus, and a range of benefits to support you across your financial, physical and mental wellbeing.
This is some of what you can expect to be doing:
Design for reliability and scalability from the outset
Implement monitoring, logging, and alerting systems
Automate deployments and operational tasks
Lead incident response and post-incident reviews
Define and maintain service level objectives (SLOs)
Support disaster recovery and resilience testing
What you’ll bring to the role
You’ll be a cloud-savvy engineer with a passion for automation and reliability. You’ll also have:
Experience with AWS and infrastructure as code
Familiarity with CI/CD pipelines and observability tools
Understanding of agile methodologies and event-driven architecture
PHP or Python development experience
Willingness to support 24x7 callout cover
Diversity, Inclusion & Belonging
We’re a Times Top 50 Employer for Gender Equality. We’re endorsed by WORK180 and we’re a partner of Diversifying. We have pledged our commitment to the Armed Forces Gold Covenant, are a Care Leaver Friendly Employer, and we’re a Disability Confident Leader. Working together with our Employee Communities, we’re wholly committed to ensuring that our people’s voices are heard, and that everyone feels a sense of belonging and pride to be a part of CityFibre. If you’d like to explore our culture and values, check out The CityFibre Way.
What you can expect from us
We want to offer you all the support you need to thrive inside and outside of work. This means giving you the tools to grow your career with us, as well as a comprehensive benefits package that you can adapt to your lifestyle. This includes 25 days annual leave, a day off on your birthday, a day off to support a charity or organisation of choice, a range of wellbeing and savings initiatives including private medical insurance, and supportive family friendly and menopause policies.
Qualifications
-
Additional information
We want to create a sense of belonging for everyone. We celebrate our differences and work to ensure everyone has the best chance to succeed, starting with our recruitment process. No matter your background, family or carer status, ethnicity, sexual orientation, religion, age, disability, gender, or gender identity, we welcome your application. If you need any support or reasonable adjustments throughout the application process, please email us at careers@cityfibre.com. We want to help!
Proud member of the Disability Confident employer scheme
Disability Confident
About Disability Confident
A Disability Confident employer will generally offer an interview to any applicant that declares they have a disability and meets the minimum criteria for the job as defined by the employer. It is important to note that in certain recruitment situations such as high-volume, seasonal and high-peak times, the employer may wish to limit the overall numbers of interviews offered to both disabled people and non-disabled people. For more details please go to Disability Confident.