previous releases, today PlayStation 4 developer m0rph3us1987 let us know on Twitter that he's abandoning the PS4Ninja project so he's decided to share the PS4Ninja file browser homebrew application's source code with PS4 community developers!
Download: ps4ninja-master.zip / GIT
From the Readme.txt, to quote: How to build
1) Go into ps4ninja_win\Browser\PS4NINJA and type
This will build minlib, ps4ninja (PS4 part) and create payload_176.bin.Code:make
2) To build the windows application, open the VS Solution and build it.
3) You can manually build any of the components by entering into the directory and type "make".
Cheers to @mota for sharing the news in the PSXHAX Shoutbox!