diff --git a/lib/customisation.nix b/lib/customisation.nix
index 16f248cd1b207..52d463602beee 100644
--- a/lib/customisation.nix
+++ b/lib/customisation.nix
@@ -261,6 +261,18 @@ rec {
       f = if isFunction fn then fn else import fn;
       fargs = functionArgs f;
 
+      aliasArgs = filterAttrs (name: _: autoArgs._isAlias or (_: false) name) fargs;
+
+      aliasErrorForArg =
+        arg:
+        let
+          loc = builtins.unsafeGetAttrPos arg fargs;
+        in
+        "Function expects alias \"${arg}\" at ${loc.file}:${toString loc.line}.";
+
+      # Only show the error for the first alias
+      aliasError = aliasErrorForArg (head (attrNames aliasArgs));
+
       # All arguments that will be passed to the function
       # This includes automatic ones and ones passed explicitly
       allArgs = intersectAttrs fargs autoArgs // args;
@@ -300,7 +312,7 @@ rec {
         else
           ", did you mean ${concatStringsSep ", " (lib.init suggestions)} or ${lib.last suggestions}?";
 
-      errorForArg =
+      missingErrorForArg =
         arg:
         let
           loc = builtins.unsafeGetAttrPos arg fargs;
@@ -309,17 +321,18 @@ rec {
         + "${loc.file}:${toString loc.line}${prettySuggestions (getSuggestions arg)}";
 
       # Only show the error for the first missing argument
-      error = errorForArg (head (attrNames missingArgs));
+      missingError = missingErrorForArg (head (attrNames missingArgs));
 
     in
-    if missingArgs == { } then
-      makeOverridable f allArgs
-    # This needs to be an abort so it can't be caught with `builtins.tryEval`,
-    # which is used by nix-env and ofborg to filter out packages that don't evaluate.
-    # This way we're forced to fix such errors in Nixpkgs,
-    # which is especially relevant with allowAliases = false
+    # These need to be abort so they can't be caught with `builtins.tryEval`,
+    # which is used by nix-env and CI to filter out packages that don't evaluate.
+    # This way we're forced to fix such errors in Nixpkgs.
+    if aliasArgs != { } then
+      abort "lib.customisation.callPackageWith: ${aliasError}"
+    else if missingArgs != { } then
+      abort "lib.customisation.callPackageWith: ${missingError}"
     else
-      abort "lib.customisation.callPackageWith: ${error}";
+      makeOverridable f allArgs;
 
   /**
     Like callPackage, but for a function that returns an attribute
@@ -365,6 +378,35 @@ rec {
     else
       mapAttrs mkAttrOverridable pkgs;
 
+  makeAlias =
+    let
+      currentRelease = lib.versions.majorMinor lib.version;
+    in
+    self: name:
+    {
+      type,
+      package ? null,
+      reason ? null,
+      release ? null,
+    }:
+    assert type == "alias";
+    if release == null then
+      self.${package}
+    else if release != currentRelease then
+      if package == null then
+        abort "Throw for '${name}' was added in ${release}. The alias must now be removed."
+      else
+        abort "Warning for '${name}' was added in ${release}. The alias must now be converted to a throw."
+    else if package == null || !self.config.allowAliases then
+      {
+        type = "error";
+        meta = throw "'${name}' was removed because it was ${reason}.";
+      }
+    else
+      lib.warnOnInstantiate
+        "'${name}' was renamed to '${package}'. The alias will be removed in the next release."
+        self.${package};
+
   /**
     Add attributes to each output of a derivation without changing
     the derivation itself and check a given condition when evaluating.
diff --git a/lib/default.nix b/lib/default.nix
index 1008025d8d181..2a7029c087359 100644
--- a/lib/default.nix
+++ b/lib/default.nix
@@ -394,6 +394,7 @@ let
         makeOverridable
         callPackageWith
         callPackagesWith
+        makeAlias
         extendDerivation
         hydraJob
         makeScope
diff --git a/pkgs/by-name/do/docker-sync/package.nix b/pkgs/by-name/do/docker-sync/package.nix
new file mode 100644
index 0000000000000..66715a3e4aace
--- /dev/null
+++ b/pkgs/by-name/do/docker-sync/package.nix
@@ -0,0 +1,5 @@
+{
+  type = "alias";
+  release = "25.11";
+  reason = "broken and unmaintained";
+}
diff --git a/pkgs/by-name/fo/follow/package.nix b/pkgs/by-name/fo/follow/package.nix
new file mode 100644
index 0000000000000..df33f156fad13
--- /dev/null
+++ b/pkgs/by-name/fo/follow/package.nix
@@ -0,0 +1,5 @@
+{
+  type = "alias";
+  release = "25.11";
+  reason = "renamed to folo";
+}
diff --git a/pkgs/by-name/op/open-timeline-io/package.nix b/pkgs/by-name/op/open-timeline-io/package.nix
new file mode 100644
index 0000000000000..c004808128f4a
--- /dev/null
+++ b/pkgs/by-name/op/open-timeline-io/package.nix
@@ -0,0 +1,5 @@
+{
+  type = "alias";
+  release = "25.11";
+  package = "opentimelineio";
+}
diff --git a/pkgs/top-level/aliases.nix b/pkgs/top-level/aliases.nix
index c0a8bebea550d..dedec70982d73 100644
--- a/pkgs/top-level/aliases.nix
+++ b/pkgs/top-level/aliases.nix
@@ -771,7 +771,6 @@ mapAliases {
   docker_27 = throw "'docker_27' has been removed because it has been unmaintained since May 2025. Use docker_28 or newer instead."; # Added 2025-06-15
   docker-compose_1 = throw "'docker-compose_1' has been removed because it has been unmaintained since May 2021. Use docker-compose instead."; # Added 2024-07-29
   docker-distribution = distribution; # Added 2023-12-26
-  docker-sync = throw "'docker-sync' has been removed because it was broken and unmaintained"; # Added 2025-08-26
   dolphin-emu-beta = dolphin-emu; # Added 2023-02-11
   dolphinEmu = throw "'dolphinEmu' has been renamed to/replaced by 'dolphin-emu'"; # Converted to throw 2024-10-17
   dolphinEmuMaster = throw "'dolphinEmuMaster' has been renamed to/replaced by 'dolphin-emu-beta'"; # Converted to throw 2024-10-17
@@ -926,7 +925,6 @@ mapAliases {
   fmt_8 = throw "fmt_8 has been removed as it is obsolete and was no longer used in the tree"; # Added 2024-11-12
   fntsample = throw "fntsample has been removed as it is unmaintained upstream"; # Added 2025-04-21
   foldingathome = throw "'foldingathome' has been renamed to/replaced by 'fahclient'"; # Converted to throw 2024-10-17
-  follow = lib.warnOnInstantiate "follow has been renamed to folo" folo; # Added 2025-05-18
   forgejo-actions-runner = forgejo-runner; # Added 2024-04-04
   fornalder = throw "'fornalder' has been removed as it is unmaintained upstream"; # Added 2025-01-25
   foundationdb71 = throw "foundationdb71 has been removed; please upgrade to foundationdb73"; # Added 2024-12-28
@@ -1839,7 +1837,6 @@ mapAliases {
   openssl_3_0 = openssl_3; # Added 2022-06-27
   opensycl = lib.warnOnInstantiate "'opensycl' has been renamed to 'adaptivecpp'" adaptivecpp; # Added 2024-12-04
   opensyclWithRocm = lib.warnOnInstantiate "'opensyclWithRocm' has been renamed to 'adaptivecppWithRocm'" adaptivecppWithRocm; # Added 2024-12-04
-  open-timeline-io = lib.warnOnInstantiate "'open-timeline-io' has been renamed to 'opentimelineio'" opentimelineio; # Added 2025-08-10
   opentofu-ls = lib.warnOnInstantiate "'opentofu-ls' has been renamed to 'tofu-ls'" tofu-ls; # Added 2025-06-10
   openvdb_11 = throw "'openvdb_11' has been removed in favor of the latest version'"; # Added 2025-05-03
   opera = throw "'opera' has been removed due to lack of maintenance in nixpkgs"; # Added 2025-05-19
@@ -1958,7 +1955,6 @@ mapAliases {
   pgroonga = throw "'pgroonga' has been removed. Use 'postgresqlPackages.pgroonga' instead."; # Added 2025-07-19
   pgtap = throw "'pgtap' has been removed. Use 'postgresqlPackages.pgtap' instead."; # Added 2025-07-19
   plv8 = throw "'plv8' has been removed. Use 'postgresqlPackages.plv8' instead."; # Added 2025-07-19
-  postcss-cli = throw "postcss-cli has been removed because it was broken"; # added 2025-03-24
   postgis = throw "'postgis' has been removed. Use 'postgresqlPackages.postgis' instead."; # Added 2025-07-19
   tegaki-zinnia-japanese = throw "'tegaki-zinnia-japanese' has been removed due to lack of maintenance"; # Added 2025-09-10
   tet = throw "'tet' has been removed for lack of maintenance"; # Added 2025-10-12
diff --git a/pkgs/top-level/by-name-overlay.nix b/pkgs/top-level/by-name-overlay.nix
index 9a011439596a0..c39c330b211f9 100644
--- a/pkgs/top-level/by-name-overlay.nix
+++ b/pkgs/top-level/by-name-overlay.nix
@@ -19,8 +19,12 @@ let
     mergeAttrsList
     ;
 
-  # Package files for a single shard
-  # Type: String -> String -> AttrsOf Path
+  inherit (lib.customisation)
+    makeAlias
+    ;
+
+  # Package imports for a single shard
+  # Type: String -> String -> AttrsOf Any
   namesForShard =
     shard: type:
     if type != "directory" then
@@ -32,14 +36,14 @@ let
       # Additionally in either of those alternatives, we would have to duplicate the hardcoding of "README.md"
       { }
     else
-      mapAttrs (name: _: baseDirectory + "/${shard}/${name}/package.nix") (
+      mapAttrs (name: _: import (baseDirectory + "/${shard}/${name}/package.nix")) (
         readDir (baseDirectory + "/${shard}")
       );
 
-  # The attribute set mapping names to the package files defining them
+  # The attribute set mapping names to the package expressions defining them
   # This is defined up here in order to allow reuse of the value (it's kind of expensive to compute)
   # if the overlay has to be applied multiple times
-  packageFiles = mergeAttrsList (mapAttrsToList namesForShard (readDir baseDirectory));
+  packages = mergeAttrsList (mapAttrsToList namesForShard (readDir baseDirectory));
 in
 # TODO: Consider optimising this using `builtins.deepSeq packageFiles`,
 # which could free up the above thunks and reduce GC times.
@@ -47,12 +51,20 @@ in
 # and ideally https://github.com/NixOS/nix/pull/8895
 self: super:
 {
+  _isAlias = name: packages.${name}.type or null == "alias";
+
   # This attribute is necessary to allow CI to ensure that all packages defined in `pkgs/by-name`
   # don't have an overriding definition in `all-packages.nix` with an empty (`{ }`) second `callPackage` argument.
   # It achieves that with an overlay that modifies both `callPackage` and this attribute to signal whether `callPackage` is used
   # and whether it's defined by this file here or `all-packages.nix`.
   # TODO: This can be removed once `pkgs/by-name` can handle custom `callPackage` arguments without `all-packages.nix` (or any other way of achieving the same result).
   # Because at that point the code in ./stage.nix can be changed to not allow definitions in `all-packages.nix` to override ones from `pkgs/by-name` anymore and throw an error if that happens instead.
-  _internalCallByNamePackageFile = file: self.callPackage file { };
+  _internalCallByNamePackageFile = fn: self.callPackage fn { };
 }
-// mapAttrs (name: self._internalCallByNamePackageFile) packageFiles
+// mapAttrs (
+  name: value:
+  if value.type or null == "alias" then
+    makeAlias self name value
+  else
+    self._internalCallByNamePackageFile value
+) packages
diff --git a/pkgs/top-level/linux-kernels.nix b/pkgs/top-level/linux-kernels.nix
index d64f7f282c8e5..b1ca6e045a7e0 100644
--- a/pkgs/top-level/linux-kernels.nix
+++ b/pkgs/top-level/linux-kernels.nix
@@ -290,31 +290,116 @@ in
 
         linux_hardened = hardenedKernelFor packageAliases.linux_default.kernel { };
       }
-      // lib.optionalAttrs config.allowAliases {
-        linux_4_19 = throw "linux 4.19 was removed because it will reach its end of life within 24.11";
-        linux_6_9 = throw "linux 6.9 was removed because it has reached its end of life upstream";
-        linux_6_10 = throw "linux 6.10 was removed because it has reached its end of life upstream";
-        linux_6_11 = throw "linux 6.11 was removed because it has reached its end of life upstream";
-        linux_6_13 = throw "linux 6.13 was removed because it has reached its end of life upstream";
-        linux_6_14 = throw "linux 6.14 was removed because it has reached its end of life upstream";
-        linux_6_15 = throw "linux 6.15 was removed because it has reached its end of life upstream";
-
-        linux_5_10_hardened = throw "linux_hardened on nixpkgs only contains latest stable and latest LTS";
-        linux_5_15_hardened = throw "linux_hardened on nixpkgs only contains latest stable and latest LTS";
-        linux_6_1_hardened = throw "linux_hardened on nixpkgs only contains latest stable and latest LTS";
-        linux_6_6_hardened = throw "linux_hardened on nixpkgs only contains latest stable and latest LTS";
-
-        linux_4_19_hardened = throw "linux 4.19 was removed because it will reach its end of life within 24.11";
-        linux_5_4_hardened = throw "linux_5_4_hardened was removed because it was broken";
-        linux_6_9_hardened = throw "linux 6.9 was removed because it has reached its end of life upstream";
-        linux_6_10_hardened = throw "linux 6.10 was removed because it has reached its end of life upstream";
-        linux_6_11_hardened = throw "linux 6.11 was removed because it has reached its end of life upstream";
-        linux_6_13_hardened = throw "linux 6.13 was removed because it has reached its end of life upstream";
-        linux_6_14_hardened = throw "linux 6.14 was removed because it has reached its end of life upstream";
-        linux_6_15_hardened = throw "linux 6.15 was removed because it has reached its end of life upstream";
-
-        linux_ham = throw "linux_ham has been removed in favour of the standard kernel packages";
-      }
+      // (
+        let
+          aliases = {
+            linux_4_19 = {
+              type = "alias";
+              release = "25.11";
+              reason = "it will reach its end of life within 24.11";
+            };
+            linux_6_9 = {
+              type = "alias";
+              release = "25.11";
+              reason = "it has reached its end of life upstream";
+            };
+            linux_6_10 = {
+              type = "alias";
+              release = "25.11";
+              reason = "it has reached its end of life upstream";
+            };
+            linux_6_11 = {
+              type = "alias";
+              release = "25.11";
+              reason = "it has reached its end of life upstream";
+            };
+            linux_6_13 = {
+              type = "alias";
+              release = "25.11";
+              reason = "it has reached its end of life upstream";
+            };
+            linux_6_14 = {
+              type = "alias";
+              release = "25.11";
+              reason = "it has reached its end of life upstream";
+            };
+            linux_6_15 = {
+              type = "alias";
+              release = "25.11";
+              reason = "it has reached its end of life upstream";
+            };
+
+            linux_5_10_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux_hardened on nixpkgs only contains latest stable and latest LTS";
+            };
+            linux_5_15_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux_hardened on nixpkgs only contains latest stable and latest LTS";
+            };
+            linux_6_1_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux_hardened on nixpkgs only contains latest stable and latest LTS";
+            };
+            linux_6_6_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux_hardened on nixpkgs only contains latest stable and latest LTS";
+            };
+
+            linux_4_19_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux 4.19 was removed because it will reach its end of life within 24.11";
+            };
+            linux_5_4_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux_5_4_hardened was removed because it was broken";
+            };
+            linux_6_9_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux 6.9 was removed because it has reached its end of life upstream";
+            };
+            linux_6_10_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux 6.10 was removed because it has reached its end of life upstream";
+            };
+            linux_6_11_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux 6.11 was removed because it has reached its end of life upstream";
+            };
+            linux_6_13_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux 6.13 was removed because it has reached its end of life upstream";
+            };
+            linux_6_14_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux 6.14 was removed because it has reached its end of life upstream";
+            };
+            linux_6_15_hardened = {
+              type = "alias";
+              release = "25.11";
+              reason = "linux 6.15 was removed because it has reached its end of life upstream";
+            };
+
+            linux_ham = {
+              type = "alias";
+              release = "25.11";
+              reason = "in favour of the standard kernel packages";
+            };
+          };
+        in
+        (lib.mapAttrs (lib.makeAlias kernels) aliases) // { _isAlias = name: aliases ? ${name}; }
+      )
     )
   );
   /*