**Introducing a new console experience for Amazon WAF**

You can now use the updated experience to access Amazon WAF functionality anywhere in the console. For more details, see [Working with the console](https://docs.amazonaws.cn/waf/latest/developerguide/working-with-console.html). 

# Supported regular expression syntax in Amazon WAF
<a name="waf-regex-pattern-support"></a>

Amazon WAF supports the regular expression pattern syntax used by the PCRE library `libpcre`. The library is documented at [PCRE - Perl Compatible Regular Expressions](http://www.pcre.org/). 

Amazon WAF doesn't support all constructs of the library. For example, it supports some zero-width assertions, but not all. We do not have comprehensive list of the constructs that are supported. However, if you provide a regex pattern that isn't valid or use unsupported constructs, the Amazon WAF API reports a failure. 

Amazon WAF does not support the following PCRE patterns: 
+ Backreferences and capturing subexpressions
+ Subroutine references and recursive patterns
+ Conditional patterns
+ Backtracking control verbs
+ The \\C single-byte directive
+ The \\R newline match directive
+ The \\K start of match reset directive
+ Callouts and embedded code
+ Atomic grouping and possessive quantifiers