diff --git a/pkgs/by-name/um/umu-launcher-unwrapped/no-umu-version-json.patch b/pkgs/by-name/um/umu-launcher-unwrapped/no-umu-version-json.patch
deleted file mode 100644
index dd4e5af1c278..000000000000
--- a/pkgs/by-name/um/umu-launcher-unwrapped/no-umu-version-json.patch
+++ /dev/null
@@ -1,13 +0,0 @@
-diff --git a/Makefile.in b/Makefile.in
-index b82053d..37db8c9 100644
---- a/Makefile.in
-+++ b/Makefile.in
-@@ -50,7 +50,7 @@ fix_shebangs:
- umu/umu_version.json: umu/umu_version.json.in
- 	$(info :: Updating $(@) )
- 	cp $(<) $(<).tmp
--	sed 's|##UMU_VERSION##|$(shell git describe --always --long --tags)|g' -i $(<).tmp
-+	sed 's|##UMU_VERSION##|@version@|g' -i $(<).tmp
- 	mv $(<).tmp $(@)
- 
- .PHONY: version
diff --git a/pkgs/by-name/um/umu-launcher-unwrapped/package.nix b/pkgs/by-name/um/umu-launcher-unwrapped/package.nix
index 8d37b284ddcb..967103de982f 100644
--- a/pkgs/by-name/um/umu-launcher-unwrapped/package.nix
+++ b/pkgs/by-name/um/umu-launcher-unwrapped/package.nix
@@ -1,51 +1,69 @@
 {
-  python3Packages,
-  fetchFromGitHub,
-  lib,
   bash,
+  cargo,
+  fetchFromGitHub,
   hatch,
+  lib,
+  python3Packages,
+  rustPlatform,
   scdoc,
-  replaceVars,
-  fetchpatch2,
+  writableTmpDirAsHomeHook,
+  withTruststore ? true,
+  withDeltaUpdates ? true,
 }:
 python3Packages.buildPythonPackage rec {
   pname = "umu-launcher-unwrapped";
-  version = "1.1.4";
+  version = "1.2.5";
 
   src = fetchFromGitHub {
     owner = "Open-Wine-Components";
     repo = "umu-launcher";
     tag = version;
-    hash = "sha256-TOsVK6o2V8D7CLzVOkLs8AClrZmlVQTfeii32ZIQCu4=";
+    hash = "sha256-bZ6Ywc524NrapkFrwFiWbqmVe1j0hunEH9YKrYQ8R2E=";
   };
 
-  # Both patches can be safely removed with the next release
-  patches = [
-    # Patch to avoid running `git describe`
-    # Fixed by https://github.com/Open-Wine-Components/umu-launcher/pull/289 upstream
-    (replaceVars ./no-umu-version-json.patch { inherit version; })
-    # Patch to use PREFIX in the installer call
-    (fetchpatch2 {
-      url = "https://github.com/Open-Wine-Components/umu-launcher/commit/602a2f84a05a63f7b1b1c4d8ca85d99fdaec2cd2.diff";
-      hash = "sha256-BMinTXr926V3HlzHHabxHKvy8quEvxsZKu1hoTGQT00=";
-    })
+  cargoDeps = rustPlatform.fetchCargoVendor {
+    inherit src;
+    hash = "sha256-nU4xZn9NPd7NgexiaNYLdo4BCbH98duZ07XYeUiceP0=";
+  };
+
+  nativeCheckInputs = [
+    writableTmpDirAsHomeHook
+    python3Packages.pytestCheckHook
   ];
 
   nativeBuildInputs = [
-    python3Packages.build
+    cargo
     hatch
-    scdoc
+    python3Packages.build
     python3Packages.installer
+    rustPlatform.cargoSetupHook
+    scdoc
   ];
 
-  pythonPath = [
-    python3Packages.filelock
-    python3Packages.xlib
-  ];
+  pythonPath =
+    with python3Packages;
+    [
+      pyzstd
+      urllib3
+      xlib
+    ]
+    ++ lib.optionals withTruststore [
+      truststore
+    ]
+    ++ lib.optionals withDeltaUpdates [
+      cbor2
+      xxhash
+    ];
 
   pyproject = false;
   configureScript = "./configure.sh";
 
+  configureFlags = [
+    "--use-system-pyzstd"
+    "--use-system-urllib"
+  ];
+
   makeFlags = [
     "PYTHONDIR=$(PREFIX)/${python3Packages.python.sitePackages}"
     "PYTHON_INTERPRETER=${lib.getExe python3Packages.python}"
@@ -54,6 +72,17 @@ python3Packages.buildPythonPackage rec {
     "SHELL_INTERPRETER=${lib.getExe bash}"
   ];
 
+  disabledTests = [
+    # Broken? Asserts that $STEAM_RUNTIME_LIBRARY_PATH is non-empty
+    # Fails with AssertionError: '' is not true : Expected two elements in STEAM_RUNTIME_LIBRARY_PATHS
+    "test_game_drive_empty"
+    "test_game_drive_libpath_empty"
+
+    # Broken? Tests parse_args with no options (./umu_run.py)
+    # Fails with AssertionError: SystemExit not raised
+    "test_parse_args_noopts"
+  ];
+
   meta = {
     description = "Unified launcher for Windows games on Linux using the Steam Linux Runtime and Tools";
     changelog = "https://github.com/Open-Wine-Components/umu-launcher/releases/tag/${version}";
diff --git a/pkgs/development/python-modules/pyzstd/default.nix b/pkgs/development/python-modules/pyzstd/default.nix
new file mode 100644
index 000000000000..62e77d821d08
--- /dev/null
+++ b/pkgs/development/python-modules/pyzstd/default.nix
@@ -0,0 +1,62 @@
+{
+  buildPythonPackage,
+  fetchFromGitHub,
+  lib,
+  pytestCheckHook,
+  setuptools,
+  zstd-c,
+}:
+buildPythonPackage rec {
+  pname = "pyzstd";
+  version = "0.16.2";
+  pyproject = true;
+
+  src = fetchFromGitHub {
+    owner = "Rogdham";
+    repo = "pyzstd";
+    tag = version;
+    hash = "sha256-Az+0m1XUFxExBZK8bcjK54Zt2d5ZlAKRMZRdr7rPcss=";
+  };
+
+  postPatch = ''
+    # pyzst specifies setuptools<74 because 74+ drops `distutils.msvc9compiler`,
+    # required for Python 3.9 under Windows
+    substituteInPlace pyproject.toml \
+        --replace-fail '"setuptools>=64,<74"' '"setuptools"'
+  '';
+
+  nativeBuildInputs = [
+    setuptools
+  ];
+
+  build-system = [
+    setuptools
+  ];
+
+  buildInputs = [
+    zstd-c
+  ];
+
+  pypaBuildFlags = [
+    "--config-setting=--global-option=--dynamic-link-zstd"
+  ];
+
+  nativeCheckInputs = [
+    pytestCheckHook
+  ];
+
+  pythonImportsCheck = [
+    "pyzstd"
+  ];
+
+  meta = {
+    description = "Python bindings to Zstandard (zstd) compression library";
+    homepage = "https://pyzstd.readthedocs.io";
+    changelog = "https://github.com/Rogdham/pyzstd/blob/${version}/CHANGELOG.md";
+    license = lib.licenses.bsd3;
+    maintainers = with lib.maintainers; [
+      MattSturgeon
+      PopeRigby
+    ];
+  };
+}
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index ed176858c674..b7393e345f78 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -11020,6 +11020,10 @@ self: super: with self; {
 
   pyzipper = callPackage ../development/python-modules/pyzipper { };
 
+  pyzstd = callPackage ../development/python-modules/pyzstd {
+    zstd-c = pkgs.zstd;
+  };
+
   plac = callPackage ../development/python-modules/plac { };
 
   plaid-python = callPackage ../development/python-modules/plaid-python { };