`node --vars` no longer does anything. It doesn't seem like this is coming back as there's radio silence on joyent/node#1536 and 0.5.5 has been tagged with the missing flag. This is just a build tweak to pull installation information from the `process` object inside of node.
In v8:r7575 (tagged at 3.2.10) v8 changed their internal mechanism for detecting context changes. Instead of using pthread_self() they are now using pthread_getspecific(). Ultimately this makes it considerably easier to build fibers into v8, but the current method is broken. Node updated v8 from 3.1.8 to 3.4.8 in e5564a3f (tagged at 0.5.2). Thus, this version of fibers only works on version of node <= 0.5.1.
This fixes the build and adds an npm package. I had to add LD_LIBRARY_PATH to fiber-shim because it fails to load if coroutine.so is not in your current working directory. This also uses a better heuristic for determining if fiber-shim was used. Also the library is now just called `fibers` when used in the context of node.