wrapper-manager

Post-modern configuration management

{pkgs, ...}: {
  # Build a custom nushell wrapper
  # that self-bundles its configuration and dependencies
  # ~/.config/nushell is not neeeded!
  wrappers.nushell = {
    basePackage = pkgs.nushell;
    prependFlags = [
      "--env-config"
      ./env.nu
      "--config"
      ./config.nu
    ];
    env.STARSHIP_CONFIG.value = ../starship.toml;
    pathAdd = [
      pkgs.starship
      pkgs.carapace
    ];
  };
}

Result (nushell executable):

#! /nix/store/51sszqz1d9kpx480scb1vllc00kxlx79-bash-5.2-p15/bin/bash -e
export STARSHIP_CONFIG=${STARSHIP_CONFIG-'/nix/store/9gyqz7x765dgh6jvjgnsmiq1zp8lm2y8-starship.toml'}
PATH=${PATH:+':'$PATH':'}
PATH=${PATH/':''/nix/store/11hrc3lnzp8jyb3afmmy9h4m4c30jkgs-starship-1.15.0/bin'':'/':'}
PATH='/nix/store/11hrc3lnzp8jyb3afmmy9h4m4c30jkgs-starship-1.15.0/bin'$PATH
PATH=${PATH#':'}
PATH=${PATH%':'}
export PATH
PATH=${PATH:+':'$PATH':'}
PATH=${PATH/':''/nix/store/vzvxm72pj68fc0120fw1k67b73iaf6g9-carapace-0.25.1/bin'':'/':'}
PATH='/nix/store/vzvxm72pj68fc0120fw1k67b73iaf6g9-carapace-0.25.1/bin'$PATH
PATH=${PATH#':'}
PATH=${PATH%':'}
export PATH
exec -a "$0" "/nix/store/k57j42qv2p1msgf9djsrzssnixlblw9v-nushell-0.82.0/bin/.nu-wrapped"  --env-config /nix/store/zx7cc0fmr3gsbxfvdri8b1pnybsh8hd9-env.nu --config /nix/store/n4mdvfbcc81i9bhrakw7r6wnk4nygbdl-config.nu "$@"

---

Wrapper-manager is a Nix library that allows you to configure your favorite applications without adding files into ~/.config. This is done by creating wrapper scripts that set the appropriate environment variables, like PATH, or pass extra flags to the wrapped program.

Nix offers very good reliability and reproducibility thanks to its read-only store. However, putting symlinks to it in your $HOME starts breaking this property. Because any program can tamper files in ~, the stability of your system is a bit more fragile.

Wrapper-manager leverages the nixpkgs' functions wrapProgram and symlinkJoin to create wrappers around your applications, providing an easy-to use interface, and also getting around some of their shortcomings.

Documentation

https://viperml.github.io/wrapper-manager

Installation and usage

Wrapper-manager is a library for creating wrappers. What you do with the wrappers is up to you, you can use them to be installed with nix-env -i, add them to your NixOS config, to a devshell, etc.

let
  # Evaluate the module system

  wm-eval = wrapper-manager.lib {
    inherit pkgs;
    modules = [
      ./other-module.nix
      {
        wrappers.hello = {
          basePackage = pkgs.hello;
          prependFlags = ["-g" "Hi"];
        };
      }
    ];
  };

  # Extract one of the wrapped packages
  myHello = wm-eval.config.wrappers.hello.wrapped;
  #=>       «derivation /nix/store/...»

  # Extract all wrapped packages
  allWrappers = wm-eval.config.build.packages;
  #=>           { hello = «derivation /nix/store/...»; }

  # Add all the wrappers to systemPackages:
  environment.systemPackages = [ ] ++ (builtins.attrValues wm-eval.config.build.packages);
  # or using the bundle:
  environment.systemPackages = [ wm-eval.config.build.toplevel ];


  # Wrap a singular package
  myGit = wrapper-manager.lib.wrapWith pkgs {
    basePackage = pkgs.git;
    env.GIT_CONFIG.value = ./gitconfig;
  };
  #=> «derivation /nix/store/...»
in
  ...

How do I get wrapper-manager.lib ?

The main entrypoint is wrapper-manager.lib. To get it:

Flakes

{
  inputs.wrapper-manager.url = "github:viperML/wrapper-manager";

  outputs = {self, wrapper-manager}: let
    # wrapper-manager.lib { ... }
  in {};
}

Npins

$ npins add github viperML wrapper-manager

let
  sources = import ./npins;
  wrapper-manager = import sources.wrapper-manager;

  # wrapper-manager.lib { ... }
in
  ...

Configuration examples

These are some examples of wrapper-manager used in the wild. Feel free to PR yours.

• https://github.com/viperML/dotfiles/tree/master/modules/wrapper-manager

To-do's

https://github.com/viperML/wrapper-manager/issues

Changelog

• 2025-06-19

  • Full rewrite
  • flags has been removed in favor of prependFlags

• 2024-08-24

  • Added postBuild option

• 2024-08-14

  • Added overrideAttrs option

• 2023-11-13

  • Added prependFlags, which maps to --add-flags
  • Added appendFlags, which maps to --append-flags
  • flags is now an alias to prependFlags, which uses --add-flags instead of --append-flags

• 2023-11-06

  • Users can now pass their own specialArgs

• 2023-10-05

  • Changed wrapper.name.env to be an attrset instead
  • Added the ability to unset a variable with wrapper.name.env.unset
  • Added the ability to disallow overriding a variable with wrapper.name.env.force
  • Changed the way wrapper.name.flags is handled so that every flag is escaped

• 2023-08-12

  • Added wrappers.name.renames option.