rbenv, as discussed in the last chapter, is an excellent tool for handling multiple versions of Ruby. However, for many projects, that’s just part of the picture. Ruby on Rails projects typically require a JavaScript engine, usually NodeJS; many Ruby apps also rely on Python libraries, and so forth and so on. It’s entirely possible to use separate tools to handle every one of these cases; many of the tools are quite similar. For example, the NodeJS version management tool nvm is reasonably familiar to Ruby developers; using it is quite like using rvm, and it is not too dissimilar to rbenv as well.