About us

World-class websites – made in York

We are Castlegate IT: an established and industry-leading web development and design company based in York. Our talented team of developers have been building high-quality, bespoke websites for more than ten years. We take pride in our straightforward, personal, and friendly approach and in the high technical standards of our work. Every website we create is unique and we love to see our clients succeed as a result of our work.

Our history

Jim Semlyen founded Semlyen IT Consultants in 2005, offering web development services to local businesses around York. Based in an office on Castlegate in the city centre, his friendly, personal approach and technical attention to detail meant the company quickly grew in size and reputation. In 2011, it became Castlegate IT Ltd and Jim was joined by Richard Lane and Andy Reading as company directors.

By 2015, the team had grown to include 12 talented designers, developers and project managers and we moved to a new, larger office on Walmgate. We are still proud to support businesses of all sizes around York, but we now have a range of national and international clients who value our dedication, honesty and high standards. The way we work hasn’t changed though: we care about our clients and we put the same attention to detail into every single project.

Our approach

We recognise that every project is different. That’s why we start by understanding your organisation and what you want from a website – then we work with you to plan, design and build a unique site that meets your needs. We offer a friendly, personal service to every client. There is no hard sell and we don’t use third-party, off-the-shelf templates – so you are guaranteed a website that’s designed just for you.

We want to make your project a success. We take the trouble to do things right first time, so our websites last longer and have the flexibility to change and grow with your company. We want to make things easy for you too: so we give you a site that is accessible and easy to use. And we continue to support you and your website for as long as you need us. We do the technical stuff, so you don’t have to!

The Castlegate IT team

Our mission, values and goals

We’ve spent many years thinking carefully about the direction of Castlegate IT, the reasons behind what we do, and why.

We believe it’s important to understand our mission and values to ensure that our team aligns with our vision. It also allows our clients to gain a better understanding of who we are, and whether we’re a good fit.

See our mission, values and goals

The CGIT ethical policy

Our ethical policy

When you work in the digital world, it’s easy to forget that what you do has an impact on the physical world. Castlegate IT is a responsible business and we pride ourselves on our honesty and integrity. Our ethical and environmental policy outlines our commitment to high standards of ethical behaviour, above and beyond our legal obligations.

Our ethical policy

Our modern slavery and human trafficking statement (PDF document)