BuildDepends

BuildDepends is a term used in software packaging to describe the set of packages required to build a piece of software from its source. In Debian and related distributions, this concept is formalized as the Build-Depends field in the package’s control metadata. Build-Depends lists compilers, build tools, libraries, and headers that are necessary for the build process but are not required to run the software after it is built.

The primary purpose of Build-Depends is to ensure a reproducible and complete build environment. Each entry may include version constraints (for example, debhelper >= 12) to guarantee that the build uses compatible tools and interfaces. Build-Depends is used by packaging tools and build daemons to install the exact prerequisites before compiling the source.

Build-Depends differs from runtime dependencies, which appear in the Depends field and are required for the installed program to operate. Build-Depends is not automatically carried into the installed package; it is used only during the build process. Some projects also use Build-Depends-Indep to specify dependencies needed for architecture-independent build components.

Common workflows involve commands such as dpkg-buildpackage to build from source, and apt-get build-dep to install the appropriate build dependencies for a given package. Tools like pbuilder, sbuild, and cowbuilder help isolate builds and ensure the environment matches the declared Build-Depends, contributing to reproducible builds.

In summary, BuildDepends captures the necessary build-time prerequisites for a package, enabling reliable, repeatable building of software from source.