diff --git a/pkgs/applications/editors/vscode/extensions/reditorsupport.r/default.nix b/pkgs/applications/editors/vscode/extensions/reditorsupport.r/default.nix
index 86b8bd729f71..595d67443c5f 100644
--- a/pkgs/applications/editors/vscode/extensions/reditorsupport.r/default.nix
+++ b/pkgs/applications/editors/vscode/extensions/reditorsupport.r/default.nix
@@ -3,9 +3,9 @@
   vscode-utils,
   jq,
   moreutils,
-  python311Packages,
   R,
   rPackages,
+  radian,
 }:
 
 vscode-utils.buildVscodeMarketplaceExtension {
@@ -20,7 +20,7 @@ vscode-utils.buildVscodeMarketplaceExtension {
     moreutils
   ];
   buildInputs = [
-    python311Packages.radian
+    radian
     R
     rPackages.languageserver
   ];
@@ -28,8 +28,8 @@ vscode-utils.buildVscodeMarketplaceExtension {
     cd "$out/$installPrefix"
     jq '.contributes.configuration.properties."r.rpath.mac".default = "${lib.getExe' R "R"}"' package.json | sponge package.json
     jq '.contributes.configuration.properties."r.rpath.linux".default = "${lib.getExe' R "R"}"' package.json | sponge package.json
-    jq '.contributes.configuration.properties."r.rterm.mac".default = "${lib.getExe python311Packages.radian}"' package.json | sponge package.json
-    jq '.contributes.configuration.properties."r.rterm.linux".default = "${lib.getExe python311Packages.radian}"' package.json | sponge package.json
+    jq '.contributes.configuration.properties."r.rterm.mac".default = "${lib.getExe radian}"' package.json | sponge package.json
+    jq '.contributes.configuration.properties."r.rterm.linux".default = "${lib.getExe radian}"' package.json | sponge package.json
   '';
   meta = {
     changelog = "https://marketplace.visualstudio.com/items/REditorSupport.r/changelog";
diff --git a/pkgs/development/python-modules/radian/default.nix b/pkgs/by-name/ra/radian/package.nix
similarity index 75%
rename from pkgs/development/python-modules/radian/default.nix
rename to pkgs/by-name/ra/radian/package.nix
index ad83654c3ab3..07b1bc68d156 100644
--- a/pkgs/development/python-modules/radian/default.nix
+++ b/pkgs/by-name/ra/radian/package.nix
@@ -1,31 +1,17 @@
 {
   lib,
-  buildPythonPackage,
+  python3Packages,
   fetchFromGitHub,
-  pytestCheckHook,
-  pyte,
-  pexpect,
-  ptyprocess,
-  pythonOlder,
-  jedi,
   git,
-  lineedit,
-  prompt-toolkit,
-  pygments,
-  rchitect,
   R,
   rPackages,
-  setuptools,
-  setuptools-scm,
 }:
 
-buildPythonPackage rec {
+python3Packages.buildPythonApplication rec {
   pname = "radian";
   version = "0.6.13";
   pyproject = true;
 
-  disabled = pythonOlder "3.9";
-
   src = fetchFromGitHub {
     owner = "randy3k";
     repo = "radian";
@@ -38,7 +24,7 @@ buildPythonPackage rec {
       --replace '"pytest-runner"' ""
   '';
 
-  build-system = [
+  build-system = with python3Packages; [
     setuptools
     setuptools-scm
   ];
@@ -48,25 +34,26 @@ buildPythonPackage rec {
   ];
 
   propagatedBuildInputs =
-    [
+    (with python3Packages; [
       lineedit
       prompt-toolkit
       pygments
       rchitect
-    ]
+    ])
     ++ (with rPackages; [
       reticulate
       askpass
     ]);
 
-  nativeCheckInputs = [
-    pytestCheckHook
-    pyte
-    pexpect
-    ptyprocess
-    jedi
-    git
-  ];
+  nativeCheckInputs =
+    (with python3Packages; [
+      pytestCheckHook
+      pyte
+      pexpect
+      ptyprocess
+      jedi
+    ])
+    ++ [ git ];
 
   makeWrapperArgs = [ "--set R_HOME ${R}/lib/R" ];
 
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 68f275e9a295..9b662e59b350 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -10175,7 +10175,6 @@ with pkgs;
       spatial
       survival
     ];
-    radian = python3Packages.radian;
     # Override this attribute to register additional libraries.
     packages = [ ];
     # Override this attribute if you want to expose R with the same set of
diff --git a/pkgs/top-level/python-aliases.nix b/pkgs/top-level/python-aliases.nix
index deae43830fe0..c0923ebe753a 100644
--- a/pkgs/top-level/python-aliases.nix
+++ b/pkgs/top-level/python-aliases.nix
@@ -665,6 +665,7 @@ mapAliases ({
   qcodes-loop = throw "qcodes-loop has been removed due to deprecation"; # added 2023-11-30
   qiskit-aqua = throw "qiskit-aqua has been removed due to deprecation, with its functionality moved to different qiskit packages";
   rabbitpy = throw "rabbitpy has been removed, since it is unmaintained and broken"; # added 2023-07-01
+  radian = throw "radian has been promoted to a top-level attribute name: `pkgs.radian`"; # added 2025-05-02
   radicale_infcloud = radicale-infcloud; # added 2024-01-07
   radio_beam = radio-beam; # added 2023-11-04
   ratelimiter = throw "ratelimiter has been removed, since it is unmaintained and broken"; # added 2023-10-21
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index fbd80431a5b1..bbd60ac8effc 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -14844,8 +14844,6 @@ self: super: with self; {
 
   rachiopy = callPackage ../development/python-modules/rachiopy { };
 
-  radian = callPackage ../development/python-modules/radian { };
-
   radicale-infcloud = callPackage ../development/python-modules/radicale-infcloud {
     radicale = pkgs.radicale.override { python3 = python; };
   };