1. An apparatus for identifying a contextual change to a source code file, in a development environment, the apparatus comprising: a computer device, including: a detector component for detecting a modification to the source code file, wherein the detector component retrieves, in response to detecting the modification to the source code file, a syntactic rule set for a programming language of the modified source code file, the syntactic rule set including a plurality of syntactic constructs for the programming language; a requester component for retrieving a previous version of the modified source code file; a parser component for parsing a first source code set associated with the source code file and a second source code set associated with the previous version of the source code file and for building an in-memory representation of the first and second source code sets, wherein the parser component, in response to the detector component retrieving the syntactic rule set and determining a plurality of relationships between the plurality of syntactic constructs, builds the in-memory representation using the syntactic rule set; a comparator component for comparing the in-memory representation of the first source code set with the in-memory representation of the second source code set in order to generate contextual information identifying a change made to a source code element associated with the modified source code set; a subscription component for receiving, from a subscriber, a subscription for notification of the generated contextual information, the subscription identifying a portion of the source code file; and a publisher component for publishing, using a data feed, the generated contextual information based on the received subscription, wherein the generated contextual information is published to the subscriber only if the comparator component identifies that a change has been made to the portion of the source code file identified by the subscriber in the subscription.