diff --git a/pkgs/development/python-modules/monai/default.nix b/pkgs/development/python-modules/monai/default.nix
index 2fe3c62f1673..9cdc1eb8b733 100644
--- a/pkgs/development/python-modules/monai/default.nix
+++ b/pkgs/development/python-modules/monai/default.nix
@@ -13,24 +13,20 @@
 
 buildPythonPackage rec {
   pname = "monai";
-  version = "1.5.0";
+  version = "1.5.1";
   pyproject = true;
 
-  disabled = pythonOlder "3.9";
-
   src = fetchFromGitHub {
     owner = "Project-MONAI";
     repo = "MONAI";
     tag = version;
-    hash = "sha256-SUZSWChO0oQlLblPwmCg2zt2Jp5QnpM1CXWnMiOiLhw=";
-    # note: upstream consistently seems to modify the tag shortly after release,
-    # so best to wait a few days before updating
+    hash = "sha256-GhyUOp/iLpuKKQAwQsA6D7IiW8ym8QTC4OmRxEKydVA=";
+    # fix source non-reproducibility due to versioneer + git-archive, as with Numba, Pytensor etc. derivations:
+    postFetch = ''
+      sed -i 's/git_refnames = "[^"]*"/git_refnames = " (tag: ${src.tag})"/' $out/monai/_version.py
+    '';
   };
 
-  postPatch = ''
-    substituteInPlace pyproject.toml --replace-fail 'torch>=2.4.1, <2.7.0' 'torch'
-  '';
-
   preBuild = ''
     export MAX_JOBS=$NIX_BUILD_CORES;
   '';
@@ -48,8 +44,6 @@ buildPythonPackage rec {
     torch
   ];
 
-  pythonRelaxDeps = [ "torch" ];
-
   env.BUILD_MONAI = 1;
 
   doCheck = false; # takes too long; tries to download data