As a PHP Developer, it's always frustrating to find an extension which just is not compatible with your current version of PHP. I have run into this problem a few times now, initially with the Cassandra extension which Datastax developed, but abandoned in favor of other languages, and more recently the php-judy extension.

I know that development of the extensions is in C / C++ (Something I've always been curious to learn more, but just never got around to), however, are there any guides / documentation regarding how to approach building a PHP extension? Or even updating an existing one to a more recent version of PHP?