Hi,
Currently, there is no new rule engine in WF4. However, the WF3 rules engine is part of .NET Framework 4, you can still use it in WF4. Below is sample about external ruleset:
External Ruleset Toolkit
http://msdn.microsoft.com/en-us/library/ee960221.aspx
Hope this information helps, thanks.
Leo Tang [MSFT]
MSDN Community Support | Feedback to us
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