diff --git a/.tool-versions b/.tool-versions
index b7c4c5b..3d664e3 100644
--- a/.tool-versions
+++ b/.tool-versions
@@ -1,2 +1,2 @@
-elixir 1.17.2-otp-27
-erlang 27.0.1
+elixir 1.19.5-otp-28
+erlang 28.3.1
diff --git a/lib/yacto/migration/structure.ex b/lib/yacto/migration/structure.ex
index d20f817..3b844fc 100644
--- a/lib/yacto/migration/structure.ex
+++ b/lib/yacto/migration/structure.ex
@@ -191,7 +191,7 @@ defmodule Yacto.Migration.Structure do
 
   def to_string(value) do
     value
-    |> Inspect.Yacto.Migration.Structure.inspect(%Inspect.Opts{})
+    |> Inspect.Yacto.Migration.Structure.inspect(%Inspect.Opts{limit: :infinity})
     |> Inspect.Algebra.format(:infinity)
     |> IO.iodata_to_binary()
   end
@@ -226,12 +226,23 @@ defimpl Inspect, for: Yacto.Migration.Structure do
       # マップをソートするオプションを付ける（Elixir 1.14 以上）
       opts = put_in(opts.custom_options[:sort_maps], true)
 
-      apply(Inspect.Map, :inspect, [
+      # Elixir 1.19.0 以降: Inspect.Map.inspect_as_struct/4 を使用、結果は {doc, opts}
+      # Elixir 1.18.4 まで: Inspect.Map.inspect/4 を使用、結果は doc
+      function_name =
+        if function_exported?(Inspect.Map, :inspect, 4),
+          do: :inspect,
+          else: :inspect_as_struct
+
+      apply(Inspect.Map, function_name, [
         value,
         Inspect.Atom.inspect(Yacto.Migration.Structure, opts),
         infos,
         opts
       ])
+      |> case do
+        {doc, _opts} -> doc
+        doc -> doc
+      end
     end
   end
 end