librdfa is a pure C implementation of a standards-compliant RDFa parser. The library is quite easy to use (there are only 5 functions). librdfa is stream-based (very little memory usage), very small (the library is around 19KB) and fast.
git clone git@github.com:rdfa/librdfa.gitThe RDFa Test Suite provides an interactive mechanism to check the conformance of an RDFa extractor. This service is intended for anybody that wants to see how RDFa works as well as developers that want to do conformance testing on their own RDFa implementations.