Projectile is a project interaction library for Emacs. Its goal is to provide a nice set of features operating on a project level without introducing external dependencies (when feasible). For instance - finding project files has a portable implementation written in pure Emacs Lisp without the use of GNU find (but for performance sake an indexing mechanism backed by external commands exists as well).

Projectile tries to be practical - portability is great, but if some external tools could speed up some task substantially and the tools are available, Projectile will leverage them.

Here's a glimpse of Projectile in action (find file in project using ido):

Projectile provides easy project management and navigation. The concept of a project is pretty basic - just a folder containing special file. Currently most VCS repos (e.g. git, mercurial, etc) are considered projects by default, as are directories containing build tools (e.g. maven, leiningen, etc) or framework markers (e.g. Ruby on Rails). If you want to mark a folder manually as a project just create an empty .projectile file in it. Some of Projectile's features:

• jump to a file in project
• jump to files at point in project
• jump to a directory in project
• jump to a file in a directory
• jump to a project buffer
• jump to a test in project
• toggle between files with same names but different extensions (e.g. .h <-> .c/.cpp, Gemfile <-> Gemfile.lock)
• toggle between code and its test (e.g. main.service.js <-> main.service.spec.js)
• jump to recently visited files in the project
• switch between projects you have worked on
• kill all project buffers
• replace in project
• multi-occur in project buffers
• grep in project
• regenerate project etags or gtags (requires ggtags).
• visit project in dired
• run make in a project with a single key chord
• browse dirty version controlled projects

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