PyXLL is licensed on a per-user basis. Each user of the PyXLL add-in needs to be licensed, regardless of whether they are a develop or an end user of the add-in.
For example, if you are a single developer with a team of 5 end users who will use PyXLL with your Python code, you would require a license for 6 users (you plus the 5 end users).
What if a user has multiple computers?
It is no problem for a single user to install PyXLL across multiple PCs. For example, installing it on a desktop and a laptop is permitted. The licensing is per-user rather than per PC.
Managing your license key with multiple users
When you purchase a subscription you will be issued with a single license key. This single license key is for up to the number of users you entered when purchasing the subscription and the same license key should be used by each user authorised to use it.
For larger deployments, to make managing your license key easier, you can reference a license file instead of the adding the key to the PyXLL config directly. A license file is simply the license key in a plain text file which can be referenced from the config using the "file" setting in the "LICENSE" section of your PyXLL config. This file can be shared on a network drive and permissioned so that only the users authorised to use this license key have access to it. This way, if you need to update the license key you only have to do it in one place.
Adding new users later
It is no problem to add new users to your subscription at any time. Once you have created your subscription via the online store (https://www.pyxll.com/store.html) you will have access to the customer portal at https://portal.pyxll.com. To log in to the portal use the same email address you used when purchasing your subscription and a 'one time password' will be emailed to you which you can use to sign in.
Once signed in to the portal. select your subscription, click 'Edit Subscription' and there you can change the quantity (number of users) your subscription is for.
When increasing the number of users you will only be charged for the increase for the remainder of the current license term (pro-rata). You will be issued a new license key for your new users. Your previous license key will also remain active and so it is not necessary to update the key for your existing users.