According to the Architecture section of the GitHub page [1]: > Ultralight is a new port of WebKit combined with a new [proprietary] lightweight renderer inten

According to the Architecture section of the GitHub page [1]: > Ultralight is a new port of WebKit combined with a new [proprietary] lightweight renderer intended specifically for embedding in apps and games. And the Licensing section: > Ultralight is free for non-commercial use and free for commercial use by companies with less than $100K gross annual revenue. For more info see LICENSE.txt Pricing [2] is available from the main web site. [1] https://github.com/ultralight-ux/Ultralight#architecture https://github.com/ultralight-ux/Ultralight#architecture [2] https://ultralig.ht/#pricing https://ultralig.ht/#pricing