Soon! After years of work PSR-6: Caching Interfaces has passed! Until now this has been the major piece for releasing a stable v1.0.0. Once this current line has been tested by the community
Right now the biggest thing holding back v1.0 is the completion of the PSR-Caching proposal. This proposal is meant to define a common caching interface that libraries such as Stash can expose to any library that desires caching. Once this is complete and we can be sure that Stash does not have anything in it that would prevent it from adopting this standard a v1.0 release will be made and the Stash API will be stabilized.
Frankly, the PEAR repositories were not getting nearly enough traffic to justify the work it took in maintaining them. With modern packaging systems like Composer it's time to move on from PEAR.
PSR's are documents published by the PHP Framework Interoperability Group, of which Stash is a member. This group attempts to make code more easily shared between libraries, frameworks and applications by creating standards that can be used to ensure interoperability. Following these standards makes Stash more portable, and Stash can take advantage of other libraries, such as monolog, that expose functionality through their own PSRs.
Yup! Some drivers may have special options that need to be set, but these are all documented.
Unfortunately xcache does not allow itself to be loaded when being run from the command line. Although this makes sense in theory, as cli scripts are not going to share memory between runs, it makes testing extremely difficult and without testing it's hard to make high quality drivers.
Because we don't have a windows box to test it on, although that may change once Travis-CI offers a solid solution.
We're happy to take requests, but even happier when they're pull requests.