Add raku to idris dev environment

devshells/idris2.nix

@@ -4,21 +4,45 @@
     {
       config,
       pkgs,
+      lib,
       inputs',
       ...
     }:
     {
-      devShells.idris2 = pkgs.mkShell {
-        buildInputs = with pkgs; [
-          # Idris toolchain
-          inputs'.nixpkgs-unstable.legacyPackages.idris2Packages.pack
-          inputs'.nixpkgs-unstable.legacyPackages.idris2
-          pkg-config
-          gmp
-          gnumake
-          chez
-          rlwrap
-        ];
-      };
+      devShells.idris2 =
+        let
+          rakudo_env = pkgs.buildEnv {
+            name = "rakudo-env";
+            paths = with pkgs; [
+              rakudo
+              zef
+            ];
+            pathsToLink = [
+              "/bin"
+              "/lib"
+              "/share"
+            ];
+          };
+          libPackages = with pkgs; [ readline70 ];
+        in
+        pkgs.mkShell {
+          buildInputs =
+            with pkgs;
+            [
+              # Idris toolchain
+              inputs'.nixpkgs-unstable.legacyPackages.idris2Packages.pack
+              inputs'.nixpkgs-unstable.legacyPackages.idris2
+              pkg-config
+              gmp
+              gnumake
+              chez
+              rlwrap
+              rakudo_env
+            ]
+            ++ libPackages;
+          shellHook = ''
+            export LD_LIBRARY_PATH=${lib.makeLibraryPath libPackages}
+          '';
+        };
     };
 }