diff --git a/pkgs/development/python-modules/unsloth-zoo/default.nix b/pkgs/development/python-modules/unsloth-zoo/default.nix
index ef2be47691bf..810628911f66 100644
--- a/pkgs/development/python-modules/unsloth-zoo/default.nix
+++ b/pkgs/development/python-modules/unsloth-zoo/default.nix
@@ -11,30 +11,42 @@
   accelerate,
   cut-cross-entropy,
   datasets,
+  filelock,
   hf-transfer,
   huggingface-hub,
   msgspec,
+  numpy,
   packaging,
   peft,
+  pillow,
+  protobuf,
   psutil,
+  regex,
   sentencepiece,
   torch,
+  torchao,
+  triton,
   tqdm,
   transformers,
   trl,
   tyro,
+  typing-extensions,
+
+  # tests
+  cudaPackages,
+  python,
 }:
 
 buildPythonPackage (finalAttrs: {
   pname = "unsloth-zoo";
-  version = "2026.3.4";
+  version = "2026.4.2";
   pyproject = true;
 
   # no tags on GitHub
   src = fetchPypi {
     pname = "unsloth_zoo";
     inherit (finalAttrs) version;
-    hash = "sha256-24w8UV5cLG5XWrU73xfmg+Jk32zl+QSPdqXLzMtmP1E=";
+    hash = "sha256-l0OTaZjPrNnrxVYIfZcf6pYr1tJS9EGj+iguU6S+D28=";
   };
 
   postPatch = ''
@@ -47,14 +59,11 @@ buildPythonPackage (finalAttrs: {
         "setuptools-scm"
   '';
 
-  # pyproject.toml requires an obsolete version of protobuf,
-  # but it is not used.
-  # Upstream issue: https://github.com/unslothai/unsloth-zoo/pull/68
+  # Upstream constrains datasets/torch more tightly than the versions
+  # currently shipped in nixpkgs, but the package still builds and works with
+  # the newer dependency set here.
   pythonRelaxDeps = [
     "datasets"
-    "protobuf"
-    "transformers"
-    "trl"
     "torch"
   ];
 
@@ -72,29 +81,59 @@ buildPythonPackage (finalAttrs: {
     accelerate
     cut-cross-entropy
     datasets
+    filelock
     hf-transfer
     huggingface-hub
     msgspec
+    numpy
     packaging
     peft
+    pillow
+    protobuf
     psutil
+    regex
     sentencepiece
     torch
+    torchao
+    triton
     tqdm
     transformers
     trl
     tyro
+    typing-extensions
   ];
 
   # No tests
   doCheck = false;
 
-  pythonImportsCheck = [ "unsloth_zoo" ];
+  # Importing touches torch.cuda at module import time and queries GPU memory.
+  dontUsePythonImportsCheck = true;
+
+  # Cover the import path on GPU-enabled runners instead of pure builders.
+  passthru.gpuCheck =
+    (cudaPackages.writeGpuTestPython.override { python3Packages = python.pkgs; }
+      {
+        libraries = ps: [ ps.unsloth-zoo ];
+      }
+      ''
+        import torch
+
+        assert torch.cuda.is_available(), "CUDA is not available"
+        assert torch.ones(1, device="cuda").is_cuda
+
+        import unsloth_zoo  # noqa: F401
+        from unsloth_zoo.device_type import DEVICE_COUNT, DEVICE_TYPE
+
+        assert DEVICE_TYPE == "cuda", DEVICE_TYPE
+        assert DEVICE_COUNT > 0, DEVICE_COUNT
+        print(f"Unsloth Zoo detected {DEVICE_COUNT} CUDA device(s)")
+      ''
+    ).gpuCheck;
 
   meta = {
     description = "Utils for Unsloth";
     homepage = "https://github.com/unslothai/unsloth_zoo";
-    license = lib.licenses.mit;
+    license = lib.licenses.lgpl3Plus;
     maintainers = with lib.maintainers; [ hoh ];
   };
 })
diff --git a/pkgs/development/python-modules/unsloth-zoo/dont-require-unsloth.patch b/pkgs/development/python-modules/unsloth-zoo/dont-require-unsloth.patch
index b5f7c9d8ddd7..7716354de65f 100644
--- a/pkgs/development/python-modules/unsloth-zoo/dont-require-unsloth.patch
+++ b/pkgs/development/python-modules/unsloth-zoo/dont-require-unsloth.patch
@@ -21,17 +21,3 @@ index 8c4404c..dc1666f 100644
  try:
      print("🦥 Unsloth: Will patch your computer to enable 2x faster free finetuning.")
  except:
-diff --git a/unsloth_zoo/device_type.py b/unsloth_zoo/device_type.py
-index 11136fb..8f8dafc 100644
---- a/unsloth_zoo/device_type.py
-+++ b/unsloth_zoo/device_type.py
-@@ -209,6 +209,9 @@ def get_device_type():
-         return "cuda"
-     elif hasattr(torch, "xpu") and torch.xpu.is_available():
-         return "xpu"
-+    else:
-+        # Allow import during tests
-+        return None
-     # Check torch.accelerator
-     if hasattr(torch, "accelerator"):
-         if not torch.accelerator.is_available():