diff --git a/pkgs/development/python-modules/dask-awkward/default.nix b/pkgs/development/python-modules/dask-awkward/default.nix
index 15accd1fb914..f7b6c0295c04 100644
--- a/pkgs/development/python-modules/dask-awkward/default.nix
+++ b/pkgs/development/python-modules/dask-awkward/default.nix
@@ -24,16 +24,16 @@
   uproot,
 }:
 
-buildPythonPackage rec {
+buildPythonPackage (finalAttrs: {
   pname = "dask-awkward";
-  version = "2025.9.0";
+  version = "2026.2.0";
   pyproject = true;
 
   src = fetchFromGitHub {
     owner = "dask-contrib";
     repo = "dask-awkward";
-    tag = version;
-    hash = "sha256-7z9SkkE4WqULW0m7lk+oohq1uwSO7XLcrnh6U7wqTgo=";
+    tag = finalAttrs.version;
+    hash = "sha256-iAecPdLbg1UhHn5rZEMYbeQGSpxYWkEFjq/mxzazG3E=";
   };
 
   build-system = [
@@ -60,7 +60,7 @@ buildPythonPackage rec {
     pytestCheckHook
     uproot
   ]
-  ++ lib.concatAttrValues optional-dependencies;
+  ++ lib.concatAttrValues finalAttrs.passthru.optional-dependencies;
 
   pythonImportsCheck = [ "dask_awkward" ];
 
@@ -85,11 +85,11 @@ buildPythonPackage rec {
   meta = {
     description = "Native Dask collection for awkward arrays, and the library to use it";
     homepage = "https://github.com/dask-contrib/dask-awkward";
-    changelog = "https://github.com/dask-contrib/dask-awkward/releases/tag/${src.tag}";
+    changelog = "https://github.com/dask-contrib/dask-awkward/releases/tag/${finalAttrs.src.tag}";
     license = lib.licenses.bsd3;
     maintainers = with lib.maintainers; [ veprbl ];
     # dask-awkward is incompatible with recent dask versions.
     # See https://github.com/dask-contrib/dask-awkward/pull/582 for context.
     broken = lib.versionAtLeast dask.version "2025.4.0";
   };
-}
+})
diff --git a/pkgs/development/python-modules/dask-histogram/default.nix b/pkgs/development/python-modules/dask-histogram/default.nix
index 98692269069d..43ef54df2672 100644
--- a/pkgs/development/python-modules/dask-histogram/default.nix
+++ b/pkgs/development/python-modules/dask-histogram/default.nix
@@ -16,16 +16,16 @@
   pytestCheckHook,
 }:
 
-buildPythonPackage rec {
+buildPythonPackage (finalAttrs: {
   pname = "dask-histogram";
-  version = "2025.2.0";
+  version = "2026.2.0";
   pyproject = true;
 
   src = fetchFromGitHub {
     owner = "dask-contrib";
     repo = "dask-histogram";
-    tag = version;
-    hash = "sha256-5Ec/qzVc/7LDG6SJym1e76BbxmbVjKKQHckwtTs1+6M=";
+    tag = finalAttrs.version;
+    hash = "sha256-F48mFKP3XLYOn4TuiU3HGHTd089kPk0dF2XnJot5s+I=";
   };
 
   build-system = [
@@ -46,8 +46,8 @@ buildPythonPackage rec {
   meta = {
     description = "Histograms with task scheduling";
     homepage = "https://dask-histogram.readthedocs.io/";
-    changelog = "https://github.com/dask-contrib/dask-histogram/releases/tag/${version}";
+    changelog = "https://github.com/dask-contrib/dask-histogram/releases/tag/${finalAttrs.src.tag}";
     license = with lib.licenses; [ bsd3 ];
     maintainers = with lib.maintainers; [ veprbl ];
   };
-}
+})