Create email feature

features/email/default.nix

@@ -0,0 +1,6 @@
+{ pkgs, ... }: {
+  imports = [
+    ./protonmail-bridge.nix
+    ./himalaya-client.nix
+  ];
+}

features/email/himalaya-client.nix

@@ -0,0 +1,17 @@
+{ pkgs, lib, ... }: {
+  environment.systemPackages =
+    let
+      # FIXME: This leads to forbidden error
+      # himalaya = toString inputs.himalaya.defaultApp."${system}".program;
+      # Wrap himalaya to be aware of ProtonMail's bridge cert.
+      himalayaWithSslEnv =
+        pkgs.writeScriptBin "h" ''
+          #!${pkgs.stdenv.shell}
+          export SSL_CERT_FILE=~/.config/protonmail/bridge/cert.pem
+          exec nix run github:srid/himalaya/nixify $*
+        '';
+    in
+    [
+      himalayaWithSslEnv
+    ];
+}