devshell
Simple per-project developer environments.
Example:
perSystem = { config, pkgs, ... }: {
devshells.default = {
env = [
{
name = "HTTP_PORT";
value = 8080;
}
];
commands = [
{
help = "print hello";
name = "hello";
command = "echo hello";
}
];
packages = [
pkgs.cowsay
];
};
};
See also the devshell project page
Installation
To use these options, add to your flake inputs:
devshell.url = "github:numtide/devshell";
and inside the mkFlake:
imports = [
inputs.devshell.flakeModule
];
Run nix flake lock and you're set.
Options
perSystem.devshells
Configure devshells with flake-parts.
Not to be confused with devShells, with a capital S. Yes, this
is unfortunate.
Each devshell will also configure an equivalent devShells.
Used to define devshells. not to be confused with devShells
Type: lazy attribute set of (submodule)
Default:
{ }
Declared by:
perSystem.devshells.<name>.commands
Add commands to the environment.
Type: list of (submodule)
Default:
[ ]
Example:
[
{
help = "print hello";
name = "hello";
command = "echo hello";
}
{
package = "nixpkgs-fmt";
category = "formatter";
}
]
Declared by:
perSystem.devshells.<name>.commands.*.package
Used to bring in a specific package. This package will be added to the environment.
Type: null or (package or string convertible to it)
Default:
null
Declared by:
perSystem.devshells.<name>.commands.*.category
Set a free text category under which this command is grouped and shown in the help menu.
Type: string
Default:
"[general commands]"
Declared by:
perSystem.devshells.<name>.commands.*.command
If defined, it will add a script with the name of the command, and the content of this value.
By default it generates a bash script, unless a different shebang is provided.
Type: null or string
Default:
null
Example:
''
#!/usr/bin/env python
print("Hello")
''
Declared by:
perSystem.devshells.<name>.commands.*.help
Describes what the command does in one line of text.
Type: null or string
Default:
null
Declared by:
perSystem.devshells.<name>.commands.*.name
Name of this command. Defaults to attribute name in commands.
Type: null or string
Default:
null
Declared by:
perSystem.devshells.<name>.devshell.packages
The set of packages to appear in the project environment.
Those packages come from https://nixos.org/NixOS/nixpkgs and can be searched by going to https://search.nixos.org/packages
Type: list of (package or string convertible to it)
Default:
[ ]
Declared by:
perSystem.devshells.<name>.devshell.packagesFrom
Add all the build dependencies from the listed packages to the environment.
Type: list of (package or string convertible to it)
Default:
[ ]
Declared by:
perSystem.devshells.<name>.devshell.interactive.<name>.deps
A list of other steps that this one depends on.
Type: list of string
Default:
[ ]
Declared by:
perSystem.devshells.<name>.devshell.interactive.<name>.text
Script to run.
Type: string
Declared by:
perSystem.devshells.<name>.devshell.load_profiles
Whether to enable load etc/profiles.d/*.sh in the shell.
Type: boolean
Default:
false
Example:
true
Declared by:
perSystem.devshells.<name>.devshell.meta
Metadata, such as ‘meta.description’. Can be useful as metadata for downstream tooling.
Type: attribute set of anything
Default:
{ }
Declared by:
perSystem.devshells.<name>.devshell.motd
Message Of The Day.
This is the welcome message that is being printed when the user opens the shell.
You may use any valid ansi color from the 8-bit ansi color table. For example, to use a green color you would use something like {106}. You may also use {bold}, {italic}, {underline}. Use {reset} to turn off all attributes.
Type: string
Default:
''
{202}🔨 Welcome to devshell{reset}
$(type -p menu &>/dev/null && menu)
''
Declared by:
perSystem.devshells.<name>.devshell.name
Name of the shell environment. It usually maps to the project name.
Type: string
Default:
"devshell"
Declared by:
perSystem.devshells.<name>.devshell.prj_root_fallback
If IN_NIX_SHELL is nonempty, or DIRENV_IN_ENVRC is set to ‘1’, then PRJ_ROOT is set to the value of PWD.
This option specifies the path to use as the value of PRJ_ROOT in case IN_NIX_SHELL is empty or unset and DIRENV_IN_ENVRC is any value other than ‘1’.
Set this to null to force PRJ_ROOT to be defined at runtime (except if IN_NIX_SHELL or DIRENV_IN_ENVRC are defined as described above).
Otherwise, you can set this to a string representing the desired default path, or to a submodule of the same type valid in the ‘env’ options list (except that the ‘name’ field is ignored).
Type: null or ((submodule) or non-empty string convertible to it)
Default:
{
eval = "$PWD";
}
Example:
{
# Use the top-level directory of the working tree
eval = "$(git rev-parse --show-toplevel)";
};
Declared by:
perSystem.devshells.<name>.devshell.prj_root_fallback.eval
Like value but not evaluated by Bash. This allows to inject other
variable names or even commands using the $() notation.
Type: null or string
Default:
null
Example:
"$OTHER_VAR"
Declared by:
perSystem.devshells.<name>.devshell.prj_root_fallback.name
Name of the environment variable
Type: string
Declared by:
perSystem.devshells.<name>.devshell.prj_root_fallback.prefix
Prepend to PATH-like environment variables.
For example name = “PATH”; prefix = “bin”; will expand the path of ./bin and prepend it to the PATH, separated by ‘:’.
Type: null or string
Default:
null
Example:
"bin"
Declared by:
perSystem.devshells.<name>.devshell.prj_root_fallback.unset
Whether to enable unsets the variable.
Type: boolean
Default:
false
Example:
true
Declared by:
perSystem.devshells.<name>.devshell.prj_root_fallback.value
Shell-escaped value to set
Type: null or string or signed integer or boolean or package
Default:
null
Declared by:
perSystem.devshells.<name>.devshell.startup.<name>.deps
A list of other steps that this one depends on.
Type: list of string
Default:
[ ]
Declared by:
perSystem.devshells.<name>.devshell.startup.<name>.text
Script to run.
Type: string
Declared by:
perSystem.devshells.<name>.env
Add environment variables to the shell.
Type: list of (submodule)
Default:
[ ]
Example:
[
{
name = "HTTP_PORT";
value = 8080;
}
{
name = "PATH";
prefix = "bin";
}
{
name = "XDG_CACHE_DIR";
eval = "$PRJ_ROOT/.cache";
}
{
name = "CARGO_HOME";
unset = true;
}
]
Declared by:
perSystem.devshells.<name>.env.*.eval
Like value but not evaluated by Bash. This allows to inject other
variable names or even commands using the $() notation.
Type: null or string
Default:
null
Example:
"$OTHER_VAR"
Declared by:
perSystem.devshells.<name>.env.*.name
Name of the environment variable
Type: string
Declared by:
perSystem.devshells.<name>.env.*.prefix
Prepend to PATH-like environment variables.
For example name = “PATH”; prefix = “bin”; will expand the path of ./bin and prepend it to the PATH, separated by ‘:’.
Type: null or string
Default:
null
Example:
"bin"
Declared by:
perSystem.devshells.<name>.env.*.unset
Whether to enable unsets the variable.
Type: boolean
Default:
false
Example:
true
Declared by:
perSystem.devshells.<name>.env.*.value
Shell-escaped value to set
Type: null or string or signed integer or boolean or package
Default:
null
Declared by:
perSystem.devshells.<name>.serviceGroups
Add services to the environment. Services can be used to group long-running processes.
Type: attribute set of (submodule)
Default:
{ }
Declared by:
perSystem.devshells.<name>.serviceGroups.<name>.description
Short description of the service group, shown in generated commands
Type: null or string
Default:
null
Declared by:
perSystem.devshells.<name>.serviceGroups.<name>.name
Name of the service group. Defaults to attribute name in groups.
Type: null or string
Default:
null
Declared by:
perSystem.devshells.<name>.serviceGroups.<name>.services
Attrset of services that should be run in this group.
Type: attribute set of (submodule)
Default:
{ }
Declared by:
perSystem.devshells.<name>.serviceGroups.<name>.services.<name>.command
Command to execute.
Type: string
Declared by:
perSystem.devshells.<name>.serviceGroups.<name>.services.<name>.name
Name of this service. Defaults to attribute name in group services.
Type: null or string
Default:
null
Declared by: