diff --git a/pkgs/by-name/wh/when-cli/package.nix b/pkgs/by-name/wh/when-cli/package.nix
new file mode 100644
index 000000000000..a15a99edf8e6
--- /dev/null
+++ b/pkgs/by-name/wh/when-cli/package.nix
@@ -0,0 +1,24 @@
+{
+  lib,
+  fetchCrate,
+  rustPlatform,
+}:
+rustPlatform.buildRustPackage rec {
+  pname = "when-cli";
+  version = "0.4.0";
+
+  src = fetchCrate {
+    inherit pname version;
+    hash = "sha256-LWssrLl2HKul24N3bJdf2ePqeR4PCROrTiVY5sqzB2M=";
+  };
+
+  cargoHash = "sha256-9emY0yhAKVzuk1Tlzi0kW8oR9jRqLdg8wbTcJMBrxMw=";
+
+  meta = {
+    description = "Command line tool for converting between timezones";
+    homepage = "https://github.com/mitsuhiko/when";
+    mainProgram = "when";
+    license = lib.licenses.asl20;
+    maintainers = with lib.maintainers; [ loicreynier ];
+  };
+}