1  {
 2    perSystem =
 3      { config, lib, ... }:
 4      {
 5        devShells =
 6          lib.concatMapAttrs
 7            (name: package: {
 8              ${name} = package.passthru.shell;
 9              ${name + "-extra"} = package.passthru.shell-extra;
10            })
11            config.packages;
12      };
13  }