# USE1.5 Software Environment

HPC systems have generally installed multiple versions of several essential software tools and software environments.
Package management tools provide access to this wide variety of software.
A user has to load the software for the current shell session to make commands available.

Some widely available software tools include:
    * Environment modules
    * SPACK
    * Conda
    * EasyBuild
    * European Environment for Scientific Software Installations (EESSI)

## Learning Outcomes

* Query available software using the package manager and select the appropriate versions for deployment in the session environment.
* Describe the MODULEPATH variable and understand shell variables relevant for executing and building software
* Query information about packages using SPACK and install as well as load and unload software modules
* Understand what conda environments are for and how a user can install their own environments
* Understand how EasyBuild is used to automate the building, installation, and management of scientific software stacks on HPC systems.
* Describe the purpose of EESSI and use its software stack to access portable, optimised scientific applications across different HPC infrastructures.

## Subskills

* [[skill-tree:use:1:5:1:b]]
* [[skill-tree:use:1:5:2:b]]
* [[skill-tree:use:1:5:3:b]]
* [[skill-tree:use:1:5:4:b]]
* [[skill-tree:use:1:5:5:b]]