skalibs is a package centralizing the free software / open source C development files used for building all software at skarnet.org: it contains essentially general-purpose libraries. You will need to install skalibs if you plan to build skarnet.org software. The point is that you won't have to download and compile big libraries, and care about portability issues, everytime you need to build a package: do it only once. skalibs can also be used as a sound basic start for C development. There are a lot of general-purpose libraries out there; but if your main goal is to produce small and secure C code with a focus on system programming, skalibs might be for you. NOTE: Upstream recommends building skarnet.org softwares with static libraries as most of skarnet.org softwares are small enough that using shared libraries are generally not worth using. Therefore, the SlackBuild script will only build the static libraries by default. If you want to also build the shared libraries, pass BUILD_SHARED=yes environment variable to the script like below: BUILD_SHARED=yes ./skalibs.SlackBuild Similarly, to avoid building the static libraries, you can pass BUILD_STATIC=no to the script. For example, to only build the shared libraries and not the static ones, you can do something like BUILD_SHARED=yes BUILD_STATIC=no ./skalibs.SlackBuild If you just want to build and use skarnet.org softwares, building only the static libraries should be sufficient.