diff --git a/lib/typeprof/core/ast/meta.rb b/lib/typeprof/core/ast/meta.rb
index b7f0b12d..600c9d20 100644
--- a/lib/typeprof/core/ast/meta.rb
+++ b/lib/typeprof/core/ast/meta.rb
@@ -250,25 +250,14 @@ def initialize(raw_node, members, kind, lenv)
 
       attr_reader :static_cpath, :members, :kind, :block_body
 
+      # Not a valid constant name, so no Ruby code can refer to it
+      BASE_CNAME = :"<struct base>"
+
+      def struct_base_cpath = @static_cpath + [BASE_CNAME]
+
       def subnodes = { block_body: }
       def attrs = { static_cpath:, members:, kind: }
 
-      # A method written in the block body (e.g. a custom initialize)
-      # overrides the auto-generated one, which should then be hidden
-      # from the RBS output.
-      def block_defines_method?(singleton, mid)
-        return false unless @block_body
-        found = false
-        @block_body.traverse do |event, node|
-          if event == :enter && node.is_a?(DefNode) &&
-             node.singleton == singleton && node.mid == mid &&
-             node.lenv.cref.cpath == @static_cpath
-            found = true
-          end
-        end
-        found
-      end
-
       # Interface expected by MethodDefBox
       def req_positionals = @kind == :struct ? @members : []
       def opt_positionals = []
@@ -283,8 +272,9 @@ def define0(genv)
         mod = genv.resolve_cpath(@static_cpath)
         # add_module_def internally calls get_const(name).add_def(self)
         cdef = mod.add_module_def(genv, self)
+        genv.resolve_cpath(struct_base_cpath).add_module_def(genv, self)
         @members.each do |member|
-          ive = genv.resolve_ivar(@static_cpath, false, member)
+          ive = genv.resolve_ivar(struct_base_cpath, false, member)
           ive.add_def(self)
         end
         @block_body.define(genv) if @block_body
@@ -295,8 +285,11 @@ def define_copy(genv)
         mod = genv.resolve_cpath(@static_cpath)
         mod.add_module_def(genv, self)
         mod.remove_module_def(genv, @prev_node)
+        base = genv.resolve_cpath(struct_base_cpath)
+        base.add_module_def(genv, self)
+        base.remove_module_def(genv, @prev_node)
         @members.each do |member|
-          ive = genv.resolve_ivar(@static_cpath, false, member)
+          ive = genv.resolve_ivar(struct_base_cpath, false, member)
           ive.add_def(self)
           ive.remove_def(@prev_node)
         end
@@ -306,8 +299,9 @@ def define_copy(genv)
       def undefine0(genv)
         mod = genv.resolve_cpath(@static_cpath)
         mod.remove_module_def(genv, self)
+        genv.resolve_cpath(struct_base_cpath).remove_module_def(genv, self)
         @members.each do |member|
-          ive = genv.resolve_ivar(@static_cpath, false, member)
+          ive = genv.resolve_ivar(struct_base_cpath, false, member)
           ive.remove_def(self)
         end
         @block_body.undefine(genv) if @block_body
@@ -320,7 +314,7 @@ def install0(genv)
           @changes.add_edge(genv, mod_val, @static_ret.vtx)
         end
 
-        cpath = @static_cpath
+        cpath = struct_base_cpath
         @members.each do |member|
           # Use bare `:member` (not `:@member`) so the slot can't collide with a
           # user-written @member ivar — Struct/Data fields are not real ivars.
@@ -357,7 +351,8 @@ def install0(genv)
 
         # Struct.[] is an alias for Struct.new
         if @kind == :struct
-          self_ret = @changes.add_escape_box(genv, Source.new(Type::Instance.new(genv, genv.resolve_cpath(cpath), [])))
+          # Struct.[] builds the struct class itself, not the base class
+          self_ret = @changes.add_escape_box(genv, Source.new(Type::Instance.new(genv, genv.resolve_cpath(@static_cpath), [])))
           @changes.add_method_def_box(genv, cpath, true, :[], init_f_args, [self_ret])
         end
 
diff --git a/lib/typeprof/core/env/module_entity.rb b/lib/typeprof/core/env/module_entity.rb
index 3d5c9a45..016023f0 100644
--- a/lib/typeprof/core/env/module_entity.rb
+++ b/lib/typeprof/core/env/module_entity.rb
@@ -285,7 +285,8 @@ def find_superclass_const_read
           when AST::ModuleNode
             return nil
           when AST::StructNewNode
-            return []  # inherits from Object (Struct < Object)
+            base_cpath = mdef.struct_base_cpath
+            return base_cpath == @cpath ? [] : base_cpath
           else
             raise
           end
diff --git a/lib/typeprof/core/service.rb b/lib/typeprof/core/service.rb
index 52d112e3..97c71fc9 100644
--- a/lib/typeprof/core/service.rb
+++ b/lib/typeprof/core/service.rb
@@ -405,7 +405,9 @@ def completion(path, trigger, pos)
                     break
                   end
                 end
-                yield mid, "#{ mod.cpath.join("::" )}#{ singleton ? "." : "#" }#{ mid } : #{ sig }" if sig
+                # The base class has no name to show
+                owner = mod.cpath.last == AST::StructNewNode::BASE_CNAME ? base_ty.mod : mod
+                yield mid, "#{ owner.cpath.join("::" )}#{ singleton ? "." : "#" }#{ mid } : #{ sig }" if sig
               end
             end
           end
@@ -481,6 +483,10 @@ def dump_declarations(path)
               s = "class #{ format_declared_const_path(node.static_cpath, stack) }"
               mod = @genv.resolve_cpath(node.static_cpath)
               superclass = mod.superclass
+              # The base class is not shown; its members are printed inline
+              while superclass && superclass.cpath.last == AST::StructNewNode::BASE_CNAME
+                superclass = superclass.superclass
+              end
               if superclass == nil
                 s << " # failed to identify its superclass"
               elsif superclass.cpath != []
@@ -499,7 +505,9 @@ def dump_declarations(path)
               end
               # Output method definitions from meta nodes (StructNewNode etc.)
               node.boxes(:mdef) do |mdef|
-                next if node.is_a?(AST::StructNewNode) && node.block_defines_method?(mdef.singleton, mdef.mid)
+                # A user-written method overrides the generated one
+                next if node.is_a?(AST::StructNewNode) &&
+                        !@genv.resolve_method(node.static_cpath, mdef.singleton, mdef.mid).defs.empty?
                 out << "  " * stack.size + "def #{ mdef.singleton ? "self." : "" }#{ mdef.mid }: " + mdef.show(@options[:output_parameter_names])
               end
             else
diff --git a/scenario/incremental/struct-new-block.rb b/scenario/incremental/struct-new-block.rb
new file mode 100644
index 00000000..4f5e606e
--- /dev/null
+++ b/scenario/incremental/struct-new-block.rb
@@ -0,0 +1,45 @@
+## update
+Dog = Struct.new(:name, :age)
+Dog.new("fred", 5)
+
+## assert
+class Dog
+  def name: -> String
+  def name=: (untyped) -> untyped
+  def age: -> Integer
+  def age=: (untyped) -> untyped
+  def initialize: (String, Integer) -> void
+  def self.[]: (String, Integer) -> Dog
+end
+
+## update
+Dog = Struct.new(:name, :age) do
+  def initialize(name, age)
+    super(name.to_s, age.to_i)
+  end
+end
+Dog.new("fred", "5")
+
+## assert
+class Dog
+  def name: -> String
+  def name=: (untyped) -> untyped
+  def age: -> Integer
+  def age=: (untyped) -> untyped
+  def self.[]: (String, Integer) -> Dog
+  def initialize: (String, String) -> void
+end
+
+## update
+Dog = Struct.new(:name, :age)
+Dog.new("fred", 5)
+
+## assert
+class Dog
+  def name: -> String
+  def name=: (untyped) -> untyped
+  def age: -> Integer
+  def age=: (untyped) -> untyped
+  def initialize: (String, Integer) -> void
+  def self.[]: (String, Integer) -> Dog
+end
diff --git a/scenario/misc/struct_new.rb b/scenario/misc/struct_new.rb
index bef9f469..af3f587c 100644
--- a/scenario/misc/struct_new.rb
+++ b/scenario/misc/struct_new.rb
@@ -91,3 +91,57 @@ def y=: (untyped) -> untyped
   def self.[]: (Integer, Integer) -> Pt
   def initialize: (?Integer, ?Integer) -> void
 end
+
+## update
+Dog = Struct.new(:name, :age) do
+  def initialize(name, age)
+    super(name.to_s, age.to_i)
+  end
+end
+Dog.new("fred", "5")
+
+## assert
+class Dog
+  def name: -> String
+  def name=: (untyped) -> untyped
+  def age: -> Integer
+  def age=: (untyped) -> untyped
+  def self.[]: (String, Integer) -> Dog
+  def initialize: (String, String) -> void
+end
+
+## update
+D = Data.define(:name, :age) do
+  def initialize(name:, age:)
+    super(name: name.to_s, age: age.to_i)
+  end
+end
+D.new(name: "fred", age: "5")
+
+## assert
+class D
+  def name: -> String
+  def age: -> Integer
+  def initialize: (name: String, age: String) -> void
+end
+
+## update
+Pt = Struct.new(:x, :y)
+class Pt
+  def initialize(x = 0, y = 0)
+    super
+  end
+end
+Pt.new(3, 4)
+
+## assert
+class Pt
+  def x: -> Integer
+  def x=: (untyped) -> untyped
+  def y: -> Integer
+  def y=: (untyped) -> untyped
+  def self.[]: (Integer, Integer) -> Pt
+end
+class Pt
+  def initialize: (?Integer, ?Integer) -> void
+end