The Sitefinity DX licensing model is domain-based, meaning that with a single license, you can register a given domain name (mywebsite.com). Sitefinity will allow you to register unlimited sub-domains for non-production purposes such as development and testing. Sitefinity DX is available in two packages tailored to different solutions. Most notably, the versions differ in the number of concurrent content editors and feature sets. A complete comparison table of all packaging options is available on our How to Buy and Sitefinity Features pages. All Sitefinity licenses are one-time fee (perpetual), with an annual service subscription fee for access to product updates and support services.