So, FINALLY, mc-dev is back to public! (thank you to whoever made that happen ) Short explanation of my problem: Browsing code via GitHub is pretty uncomfortable, so having it directly within eclipse is the best solution for me. There are 3 parts of the code I need to access: Bukkit, CraftBukkit, mc-dev (the latter being all classes not contained in CraftBukkit). To get the first two combined, I simply used to download both CB and Bukkit source from GitHub, throw them together in one zip file and add it as a source attachment to the craftbukkit.jar library. All worked fine and dandy. Just, as stated above, with the problem that all unmodified net.minecraft.server (=NMS) classes were missing, because they are only in mc-dev (which was private since the update until now). In my head, I imagined adding that code being just as simple when it would be back public: Simply throw the files to all the other craftbukkit NMS ones (making sure not to overwrite anything). But it apparently doesn't work like that. From the research I did, I assume that the linked native unmodified NMS ".class" files within the compiled jar don't contain that information about the "SourceFile" they were compiled off of. That way, Eclipse doesn't recognize the .java files, even though they are there. Could that actually be the case? Has anyone a solution to that? My only requirement is: Being able to browse NMS classes that are not in the CraftBukkit repository from within Eclipse (while still having access to the rest of the source, but that should be the easy part that I already have). Thanks in advance!