Principal Application Developer

CityFibre Limited; Milton Keynes; On-site; GBP 50,000 - 75,000; Full time

Job summary

CityFibre Limited, the UK's largest fibre-only network, is seeking a Principal Application Developer to lead the development of their Inventory Management Ecosystem. This role involves designing scalable software, mentoring developers, and collaborating with architects to innovate and enhance network management, with a strong focus on clean code and agile practices. Join a company leading the charge in digital infrastructure and contribute to significant advancements in connectivity and technology.

Benefits

25 days annual leave

Birthday off

Charity day off

Private medical insurance

Family-friendly policies

Qualifications

• Proven experience in PHP or Python development.
• Strong knowledge of Laravel and MVC design patterns.
• Experience with microservices, Apache Kafka, and event-driven architecture.

Responsibilities

• Leading the design and development of scalable software solutions.
• Providing technical leadership and mentorship to developers.
• Driving improvements in code quality, testing, and development processes.

Skills

PHP

Python

Microservices

Agile

DevOps

CI/CD

Communication

Tools

Git

PHPUnit

PyTest

Job description

CityFibre provides wholesale connectivity to multiple business and consumer service providers, local authorities and mobile operators.

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 aPrincipal Application Developer – Inventory Management Ecosystem (IME)

Are you ready to shape the future of software delivery in a fast-paced, DevOps-driven environment? We’re looking for aPrincipal Application Developerto lead the technical vision and development of our Inventory Management Ecosystem (IME), ensuring it supports scalable, resilient, and innovative network and service management.

You’ll receive acompetitive salary, aperformance-related bonus, and arange of benefitsto support your financial, physical, and mental wellbeing.

This is some of what you can expect to be doing:

• Leading the design and development of scalable software solutions within the IME Release Train
• Providing technical leadership and mentorship to developers, fostering a culture of learning and innovation
• Collaborating with Enterprise and Solution Architects to translate architectural designs into actionable development plans
• Driving improvements in code quality, testing, and development processes using Agile and DevOps principles
• Working closely with internal teams and external partners to ensure seamless integration and delivery of third-party systems
• Supporting the reduction of technical debt and introducing new development processes to improve efficiency
• Maintaining strong relationships with architecture, QA, and operations teams to ensure high-quality, reliable software delivery

What you’ll bring to the role

You’ll bring deep technical expertise, a passion for clean, scalable code, and a collaborative mindset.You’ll also have:

• Proven experience in PHP or Python development, with strong knowledge of frameworks like Laravel and design patterns such as MVC
• Experience working with microservices, Apache Kafka, and event-driven architecture
• A track record of mentoring developers and leading technical initiatives in Agile environments
• Familiarity with DevOps practices, CI/CD pipelines, and tools like Git, PHPUnit, or PyTest
• Strong communication and stakeholder engagement skills, with the ability to influence and collaborate across teams
• A continuous improvement mindset and a passion for staying ahead of emerging technologies

Diversity, Inclusion & Belonging

We’re a Times Top 50 Employer for Gender Equality. We’re endorsed byWORK180 and we’re a partner ofDiversifying . We have pledged our commitment to the Armed Forces Covenant and we’re a Disability Confident Employer. Working together with our Employee Networks, 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 outThe 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.

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 [e-mail]. We want to help!