feat(machoke): add in-memory store

configs/nixos/modules/shell/fish/config.fish

@@ -3,6 +3,8 @@ set -g fish_key_bindings fish_vi_key_bindings
 
 set -gx EDITOR nvim
 set -gx VISUAL nvim
+# TODO: source this from a shell toolchain registry.
+set -gx RUST_TOOLCHAIN_ROOT /nix/store/ph2z7wfzcxyrl1y0349dzcjkas3bifhw-rust-toolchain
 
 # Render man pages through bat.
 set -x MANROFFOPT "-c"

configs/nixos/modules/shell/fish/default.nix

@@ -9,11 +9,7 @@ let
   cfg = config.modules.shell.fish;
   user = config.user.name;
   shortcuts = config.registry.shell-shortcut.${config.networking.hostName};
-  envVars = config.registry.env-var.${config.networking.hostName};
   commandsOf = shortcuts: lib.mapAttrs (_name: shortcut: shortcut.command) shortcuts;
-  exportEnvVar = name: value: ''
-    set -gx ${name} ${lib.escapeShellArg value}
-  '';
 in
 {
   options.modules.shell.fish = {
@@ -103,10 +99,7 @@ in
         };
 
         # Rendered by home-manager into ~/.config/fish/config.fish.
-        interactiveShellInit = lib.concatStringsSep "\n" (
-          (lib.mapAttrsToList exportEnvVar envVars)
-          ++ [ (builtins.readFile ./config.fish) ]
-        );
+        interactiveShellInit = builtins.readFile ./config.fish;
       };
     };
   };

configs/nixos/modules/shell/rust.nix

@@ -23,13 +23,13 @@ in
   options.modules.shell.rust.enable = lib.mkEnableOption "Rust tools for the primary user's shell environment";
 
   config = lib.mkIf cfg.enable {
-    registry.env-var.${config.networking.hostName}.RUST_TOOLCHAIN_ROOT = "${toolchain}";
-
     home-manager.users.${user} = {
       home.packages = [
         toolchain
         pkgs.rust-analyzer
       ];
+
+      home.sessionVariables.RUST_TOOLCHAIN_ROOT = "${toolchain}";
     };
   };
 }

configs/nixos/registry/env-var.nix

@@ -1,4 +0,0 @@
-{ lib, ... }:
-{
-  type = lib.types.str;
-}