diff --git a/pkgs/development/python-modules/yasi/default.nix b/pkgs/development/python-modules/yasi/default.nix
deleted file mode 100644
index 0676f058b4bf..000000000000
--- a/pkgs/development/python-modules/yasi/default.nix
+++ /dev/null
@@ -1,43 +0,0 @@
-{
-  lib,
-  buildPythonPackage,
-  colorama,
-  fetchFromGitHub,
-  pytestCheckHook,
-  setuptools,
-}:
-
-buildPythonPackage rec {
-  pname = "yasi";
-  version = "2.1.2";
-  pyproject = true;
-
-  src = fetchFromGitHub {
-    owner = "nkmathew";
-    repo = "yasi-sexp-indenter";
-    rev = "v${version}";
-    hash = "sha256-xKhVTmh/vrtBkatxtk8R4yqbGroH0I+xTKNYUpuikt4=";
-  };
-
-  nativeBuildInputs = [ setuptools ];
-
-  propagatedBuildInputs = [ colorama ];
-
-  nativeCheckInputs = [ pytestCheckHook ];
-
-  postPatch = ''
-    substituteInPlace setup.py \
-      --replace "test.test_yasi" "tests.test_yasi"
-  '';
-
-  pythonImportsCheck = [ "yasi" ];
-
-  meta = {
-    description = "Dialect-aware s-expression indenter written in Python and newLISP";
-    mainProgram = "yasi";
-    homepage = "https://github.com/nkmathew/yasi-sexp-indenter";
-    changelog = "https://github.com/nkmathew/yasi-sexp-indenter/blob/${src.rev}/CHANGELOG.md";
-    license = lib.licenses.mit;
-    maintainers = [ ];
-  };
-}
diff --git a/pkgs/top-level/python-aliases.nix b/pkgs/top-level/python-aliases.nix
index db858b4ee0b2..025961acf9de 100644
--- a/pkgs/top-level/python-aliases.nix
+++ b/pkgs/top-level/python-aliases.nix
@@ -541,6 +541,7 @@ mapAliases {
   XlsxWriter = throw "'XlsxWriter' has been renamed to/replaced by 'xlsxwriter'"; # Converted to throw 2025-10-29
   y-py = throw "'y-py' has been removed as it was archived upstream; consider using 'pycrdt' instead"; # Added 2026-01-21
   Yapsy = throw "'Yapsy' has been renamed to/replaced by 'yapsy'"; # Converted to throw 2025-10-29
+  yasi = throw "'yasi' has been removed as it is unmaintained upstream"; # Added 2026-01-31
   ypy-websocket = throw "'ypy-websocket' has been removed as it was archived upstream; consider using 'pycrdt-websocket' instead"; # Added 2026-01-21
   z3 = throw "'z3' has been renamed to/replaced by 'z3-solver'"; # Converted to throw 2025-10-29
   zc-buildout221 = throw "'zc-buildout221' has been renamed to/replaced by 'zc-buildout'"; # Converted to throw 2025-10-29
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index f8fe9b9d571d..4133138b4d8f 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -21056,8 +21056,6 @@ self: super: with self; {
 
   yarl = callPackage ../development/python-modules/yarl { };
 
-  yasi = callPackage ../development/python-modules/yasi { };
-
   yaspin = callPackage ../development/python-modules/yaspin { };
 
   yaswfp = callPackage ../development/python-modules/yaswfp { };