Smalltalk provides many reflective features, yet behavioral reflection is limited. Pharo provides reflective features that go beyond standard Smalltalk. The lecture will present Reflectivity, a framework for fine-grained behavioral reflection. It allows to annotate the AST with MetaLinks, alowing meta-objects to change behavior down to a single operation. After a overview of the framework, we show how MetaLinks are used in Pharo to realize IDE tools such as BreakPoints and Code Coverage.