Automatically determining and setting the PRJ_ROOT environment variable.
- git rev-parse --show-toplevel is used for this. If the project is not a git repository, this will default to $PWD instead.
Automatically determining and setting the PRJ_DATA_DIR environment variable. (Disable with setDataDir = false;)
- Automatically creating the PRJ_DATA_DIR directory ($PRJ_ROOT/.data). (Disable with createDataDir = false;)

This is meant to offer some of the utility of something like devshell without the extraneous dependencies.

Usage #

{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    systems.url = "github:nix-systems/default";
    tinyshell.url = "git+https://tangled.org/csw.im/tinyshell";
  };

  outputs = {
    nixpkgs,
    systems,
    tinyshell,
    ...
  }: let
    eachSystem = f: (nixpkgs.lib.genAttrs (import systems) (
      system: f system (import nixpkgs {inherit system;})
    ));
  in {
    devShells = eachSystem (system: pkgs: {
      default = (tinyshell.lib pkgs).mkTinyShell {
        shellHook = ''echo "Project root: $PRJ_ROOT"'';
      };
    });
  };
}

Templates #

tinyshell offers some minimal templates to get you started.

`simple` (`default`) #

Just the bare-bones tinyshell. No flake-utils, nothing extra but nix-systems.

nix flake init -t git+https://tangled.org/csw.im/tinyshell#simple

`nixhooks` #

A tinyshell with nixhooks configured.

nix flake init -t git+https://tangled.org/csw.im/tinyshell#nixhooks

Function Reference #

Exported functions #

Function	Underlying implementation	Description
`mkTinyShell`	`pkgs.mkShell`	Creates a development shell with the tinyshell project-root and data-directory setup.
`mkTinyShellNoCC`	`pkgs.mkShellNoCC`	Same tinyshell setup, using `pkgs.mkShellNoCC` for shells that do not need a C compiler toolchain by default.

`_mkTinyShell` Arguments #

All arguments understood by tinyshell (those listed below, aside from ...) are removed from the arguments passed through to the underlying mkShell implementation.

Argument	Type	Default	Description
`shellHook`	String	`""`	Additional shell commands appended to the generated shell hook.
`projectVarName`	String	`PRJ_ROOT`	The name of the environment variable to export the project's root directory to.
`dataDirVarName`	String	`PRJ_DATA_DIR`	The name of the environment variable to export the project's data directory to.
`dataDir`	String or `null`	`".data"`	Relative path to the project data directory, resolved against `projectVarName`. Set to `null` to disable data-directory configuration and creation.
`setDataDir`	Boolean	`dataDir != null`	Whether to export `${dataDirVarName}` as `${projectVarName}/${dataDir}`.
`createDataDir`	Boolean	`setDataDir`	Whether to create the directory specified by `dataDirVarName` using `mkdir -vp`. Requires `setDataDir = true`.
`gitPackage`	Derivation	`pkgs.git`	Git package used to determine the project root with `git rev-parse --show-toplevel`. Falls back to `$PWD` if the command fails.
`...`	—	—	Accepts additional arguments supported by `pkgs.mkShell` or `pkgs.mkShellNoCC`, such as `packages`, `buildInputs`, and `nativeBuildInputs`.