Aura provides clean, fully decoupled libraries and independent libraries for PHP 5.4+ that can be used in any database, alone, in concert with each other, or into a full-stack framework of their own. It's the second major revision of Solar, rewritten as a library collection with dependency injection. It provides high-quality, well-tested, standards-compliant library packages that can be used in any codebase, with each library being self-contained and independently downloadable. There are enough libraries to form a full framework and be used for application development. As Aura is intended to take advantage of PHP5.4+, it features formal namespaces, anonymous functions, late static binding, short array syntax, traits, and more that aren't available in earlier versions of PHP.