Configuration Files And Templates

Overview

Configuration files and templates are split into common configuration files, container recipes, site configurations, and templates.

Common configuration files

Several configuration files in YAML format are stored under configs/common:

Name	Description
config.yaml	Basic settings like number of parallel build processes, location of spack cache
modules*.yaml	Generic module configuration, and settings for Tcl/Tk environment modules and Lua/Lmod modules
packages.yaml	Generic package configuration (providers, versions, build variants)
packages_*.yaml	Compiler-specific package configuration that overrides the generic package configuration *

* Currently, spack-stack does not support version-specific compiler configuration files in configs/common (different from site configurations)

Container recipes

Currently unused. Will be removed or updated later.

Site configurations

Site configurations are split into fully supported tier-1 sites (preconfigured sites) and tier-2 sites (configurable sites). The latter include default site configurations for Linux and macOS that serve as starting points for new site configurations and user systems.

Site configurations and common configurations are merged when creating new environments with spack-stack. Conflicts are resolved by overriding the common configuration with the site-specific configuration, where possible, or an error is generated.

For each site, the following configuration files can be present:

Name	Description
config.yaml	Basic settings
mirrors.yaml	Definition of source cache and build cache mirrors
modules.yaml	Choice between tcl and lmod modules, and which additional modules to be included (generated) or excluded by spack
packages.yaml	Compiler-independent package settings for this site
packages_*.yaml	Compiler-specific package settings; these can include specific versions, for example packages_gcc-12.2.0.yaml and packages_gcc-13.4.0.yaml
README.md	Additional information for this site

The site configuration for each site must provide information on the compiler and MPI provider (packages.yaml, packages_*.yaml) and which modules to generate (modules.yaml).

Templates

Templates are used by the spack-stack extension to create environments or containers and define which packages, including virtual packages, need to be installed. In some cases, variants and versions are specified in the templates. This is mostly used when different environments (templates) require different settings, in which case the common package configuration file allows multiple versions/build options or does not specify them at all.

Each of the available templates corresponds to a specific environment in the following table. Environment names take the format PREFIX-COMPILER-VERSION, for example `ue-oneapi-2025.3.0.

Template	Description	Prefix
unified-dev	Unified environment for all organizations/applications	ue
skylab-dev	JEDI/Skylab environment for JEDI, models, EWOK	se
neptune-dev	NEPTUNE-JEDI standalone environment	ne
neptune-ops	NEPTUNE-JEDI standalone environment for operations	ne
`cylc-dev``	Environment for running cylc (separate from other envs)	ce
gsi-addon-dev	GSI addon (chained) environment on top of unified env.	gsi