Terminology

• package: a package is a set of libraries, executables, ... that are built and installed as one by opam
• project: a project is a source tree, maybe containing one or more packages
• root: the root is the directory from where Jbuilder can build things. Jbuilder knows how to build targets that are descendents of the root. Anything outside of the tree starting from the root is considered part of the installed world. How the root is determined is explained in this section.
• workspace: the workspace is the subtree starting from the root. It can contain any number of projects that will be built simultaneously by jbuilder
• installed world: anything outside of the workspace, that Jbuilder takes for granted and doesn’t know how to build
• build context: a build context is a subdirectory of the <root>/_build directory. It contains all the build artifacts of the workspace built against a specific configuration. Without specific configuration from the user, there is always a default build context, which corresponds to the environment in which Jbuilder is executed. Build contexts can be specified by writing a jbuild-workspace file
• build context root: the root of a build context named foo is <root>/_build/<foo>
• alias: an alias is a build target that doesn’t produce any file and has configurable dependencies. Alias are per-directory and some are recursive; asking an alias to be built in a given directory will trigger the construction of the alias in all children directories recursively. The most interesting ones are:
  • runtest which runs user defined tests
  • install which depends on everything that should be installed