diff --git a/pkgs/by-name/cl/classads/package.nix b/pkgs/by-name/cl/classads/package.nix
deleted file mode 100644
index 9e15be4e8591..000000000000
--- a/pkgs/by-name/cl/classads/package.nix
+++ /dev/null
@@ -1,38 +0,0 @@
-{
-  lib,
-  stdenv,
-  fetchurl,
-  autoreconfHook,
-  pcre,
-}:
-
-stdenv.mkDerivation (finalAttrs: {
-  pname = "classads";
-  version = "1.0.10";
-
-  src = fetchurl {
-    url = "ftp://ftp.cs.wisc.edu/condor/classad/c++/classads-${finalAttrs.version}.tar.gz";
-    sha256 = "1czgj53gnfkq3ncwlsrwnr4y91wgz35sbicgkp4npfrajqizxqnd";
-  };
-
-  nativeBuildInputs = [ autoreconfHook ];
-
-  buildInputs = [ pcre ];
-
-  configureFlags = [
-    "--enable-namespace"
-    "--enable-flexible-member"
-  ];
-
-  # error: use of undeclared identifier 'finite'; did you mean 'isfinite'?
-  env.NIX_CFLAGS_COMPILE = lib.optionalString (
-    stdenv.hostPlatform.isDarwin && stdenv.hostPlatform.isAarch64
-  ) "-Dfinite=isfinite";
-
-  meta = {
-    homepage = "http://www.cs.wisc.edu/condor/classad/";
-    description = "Classified Advertisements library provides a generic means for matching resources";
-    license = lib.licenses.asl20;
-    platforms = lib.platforms.unix;
-  };
-})
diff --git a/pkgs/top-level/aliases.nix b/pkgs/top-level/aliases.nix
index 986a37e07249..c84e0c803996 100644
--- a/pkgs/top-level/aliases.nix
+++ b/pkgs/top-level/aliases.nix
@@ -530,6 +530,7 @@ mapAliases {
   clang_17 = throw "clang_17 has been removed, as it is unmaintained and obsolete"; # Added 2025-08-09
   clashmi = throw "'clashmi' has been removed, as it is unmaintained in nixpkgs"; # Added 2026-01-31
   clasp = throw "'clasp' has been renamed to/replaced by 'clingo'"; # Converted to throw 2025-10-27
+  classads = throw "'classads' has been removed, as it is unmaintained both upstream and in nixpkgs"; # Added 2026-06-27
   claude-code-acp = warnAlias "'claude-code-acp' has been renamed to 'claude-agent-acp'" claude-agent-acp; # Added 2026-03-31
   claude-code-bin = warnAlias "'claude-code-bin' has been merged into 'claude-code'" claude-code; # Added 2026-04-18
   clearlyU = clearly-u; # Added 2026-02-08