After discussing with moderators we've updated the open source rule due to the introduction of PD3 mods which were a bit questionable with the current rule.

Previously

Your mod must be open source.
There might be an exception if you use some libraries from trusted sources. If your mod is compiled or obfuscated in some way, you must include a repository link.

New

Your submission must be open source.

If your submission contains any code that is compiled or obfuscated in some way (Any programming language, including visual ones such as Unreal Engine BPs), 
you must include a repository link or include the source code in some way.

Exceptions may be made for known and trusted libraries, at the discretion of MWS Staff.

If your mod is a simple asset replacement it is not required to be open source (Given it's not containing code/blueprints).

Examples of mods that won't be affected:

• Textures
• Models
• Sounds/Music

Examples of mods that may be affected:

• Maps

Examples of mods that are affected:

• BP mods.