Permissions at a glance
These are the proposed licensing rules. The agreement accompanying your version determines the effective grant.
| Use | Official precompiled SDK | Purchased engine source |
|---|---|---|
| Commercial applications | Allowed, royalty-free | Internal use; separate grant to ship |
| Redistribute official SDK or runtime | Allowed, standalone or with an app | Separate SDK rights still apply |
| Keep application source private | Allowed | Allowed; no engine redistribution |
| Modify engine implementation | No engine source grant | Allowed internally within the grant |
| Distribute engine source or patches containing it | Not included | Prohibited |
| Ship source-built engines or EXEs containing them | Apps linked with official static libraries may ship | Prohibited without separate written permission |
Two agreements
The free SDK license covers official binaries and designated integration materials. The commercial source license covers paid engine implementation deliveries. Each applies to its own materials. Your application code, interfaces and independent extensions are not brought under engine source restrictions merely by calling an API.
A distribution example
You may use the official kui.dll with your own HTML/CSS, Lua and native application, sell that application without publishing its source, and redistribute the official SDK. If you buy engine source, modify the layout implementation and compile a new kui.dll, that DLL is for authorized internal use only. Shipping it with a customer application also needs separate written permission. Recompiling an unchanged engine is subject to the same restriction.
Third-party licenses remain in force
Third-party components retain their own licenses. Preserve release-specific licenses and notices and meet applicable source and relinking obligations when distributing them. Custom terms can govern only KUI content the licensor is entitled to license; they cannot remove upstream rights.
Draft status and covered versions
Revision 0.1 · Draft, not yet effective. These terms apply only when an authorized licensor supplies a final agreement with a specified SDK or source order. Display on this website does not change existing licenses. The current local repository and SDK still include MIT texts; package licenses, ownership and third-party notices must be reconciled before a release under the new terms.
License classification
This is a proprietary licensing model with free binaries and paid commercial source access. Restrictions on redistribution of engine source and source-built derivatives are not open-source licensing. The source should not be labeled MIT, Apache or GPL, and those names should not describe the custom agreement. Rights in copies already supplied under another license remain governed by that license.
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