pkgconf provides compiler and linker configuration for development frameworks.
pkgconf is a program which helps to configure compiler and linker flags for development frameworks. It is similar to pkg-config, but was written from scratch in the summer of 2011 to replace pkg-config, which now needs itself to build itself (or you can set a bunch of environment variables, both are pretty ugly).
Implementations of pkg-config, such as pkgconf, are typically used with the PKG_CHECK_MODULES autoconf macro. As far as I (nenolod) know, pkgconf is compatible with all known variations of this macro. pkgconf detects at runtime whether or not it was started as 'pkg-config', and if so, attempts to set program options such that its behaviour is similar.
In terms of the autoconf macro, it is possible to specify the PKG_CONFIG environment variable, so that you can test pkgconf without overwriting your pkg-config binary. (hint: export PKG_CONFIG=/usr/bin/pkgconf) However, if you do this, it will be running in native mode, so you may have some very strange results as the dependency graph is compiled differently in native mode.
pkgconf builds an acyclic directed dependency graph. This allows for the user to more conservatively link their binaries -- which may be helpful in some environments, such as when prelink(1) is being used. As a result of building a directed dependency graph designed for the specific problem domain provided by the user, more accurate dependencies can be determined. pkg-config, on the other hand builds a database of all known pkg-config files on the system before attempting to resolve dependencies, which is a considerably slower and less efficient design.
pkgconf also does not bundle any third-party libraries or depend on any third-party libraries, making it a great tool for embedded systems and distributions with security concerns.
pkgconf is basically compiled the same way any other autotools-based project is compiled:
$ ./configure
$ make
$ sudo make install
Release tarballs are available at https://tortois.es/~nenolod/distfiles/.