Before I say anything, I want to say that I always used Phobos because I do not want to sound to some people like Tango advocate. I humbly believe Tango is still superior in many places comparing to Phobos. Take a look at Tango conduits for an example, and you will understand what I mean. Tango has been made to be a framework ready for enterprise use, and I seriously believe Tango, if ported to work on top of druntime and phobos will still attract users.
I live in Java world nowadays, where Java IO and NIO 1 and 2 are standards. Tango is very close to NIO, and I believe it has been modeled after Java NIO. Kudos to designers and developers. I always wished it had been refactored to work on top of Phobos, which I still count as a low-level library.
In my perfect D world, druntime would be the lowest level library, phobos little bit higher, but still low level, and the third layer would be Tango, with all high-level features it possesses.
Kind regards
