diff --git a/lib/caotral/linker.rb b/lib/caotral/linker.rb
index 58f97c8..e2d3e7a 100644
--- a/lib/caotral/linker.rb
+++ b/lib/caotral/linker.rb
@@ -5,16 +5,18 @@
 
 module Caotral
   class Linker
-    def self.link!(inputs:, output: "a.out", linker: "mold", debug: false, shared: false) = new(inputs:, output:, linker:, debug:, shared:).link
+    def self.link!(inputs:, output: "a.out", linker: "mold", debug: false, shared: false, executable: true)
+      new(inputs:, output:, linker:, debug:, shared:, executable:).link
+    end
 
-    def initialize(inputs:, output: "a.out", linker: "mold", linker_options: [], shared: false, debug: false)
+    def initialize(inputs:, output: "a.out", linker: "mold", linker_options: [], executable: true, shared: false, debug: false)
       @inputs, @output, @linker = inputs, output, linker
       @options = linker_options
-      @debug, @shared = debug, shared
+      @executable, @debug, @shared = executable, debug, shared
     end
 
-    def link(inputs: @inputs, output: @output, debug: @debug, shared: @shared)
-      return to_elf(inputs:, output:, debug:) if @linker == "self"
+    def link(inputs: @inputs, output: @output, debug: @debug, shared: @shared, executable: @executable)
+      return to_elf(inputs:, output:, debug:, shared:, executable:) if @linker == "self"
 
       IO.popen(link_command).close
     end
@@ -47,12 +49,14 @@ def link_command(inputs: @inputs, output: @output)
     def libpath = @libpath ||= File.dirname(Dir.glob("/usr/lib*/**/crti.o").last)
     def gcc_libpath = @gcc_libpath ||= File.dirname(Dir.glob("/usr/lib/gcc/x86_64-*/*/crtbegin.o").last)
 
-    def to_elf(inputs: @inputs, output: @output, debug: @debug)
+    def to_elf(inputs: @inputs, output: @output, debug: @debug, shared: @shared, executable: @executable)
       elf_objs = inputs.map { |input| Caotral::Binary::ELF::Reader.new(input:, debug:).read }
-      builder = Caotral::Linker::Builder.new(elf_objs:)
+      builder = Caotral::Linker::Builder.new(elf_objs:, debug:, shared:, executable:)
       builder.resolve_symbols
       elf_obj = builder.build
-      Caotral::Linker::Writer.new(elf_obj:, output:, debug:).write
+      Caotral::Linker::Writer.new(elf_obj:, output:, debug:, shared:, executable:).write
+      File.chmod(0755, output) if executable
+      output
     end
   end
 end
diff --git a/lib/caotral/linker/builder.rb b/lib/caotral/linker/builder.rb
index f95934b..fc97df7 100644
--- a/lib/caotral/linker/builder.rb
+++ b/lib/caotral/linker/builder.rb
@@ -14,10 +14,10 @@ class Builder
 
       attr_reader :symbols, :executable, :debug
 
-      def initialize(elf_objs:, executable: true, debug: false)
+      def initialize(elf_objs:, executable: true, debug: false, shared: false)
         @elf_objs = elf_objs
+        @executable, @debug, @shared = executable, debug, shared
         @symbols = { locals: Set.new, globals: Set.new, weaks: Set.new }
-        @executable, @debug = executable, debug
       end
 
       def build
diff --git a/lib/caotral/linker/writer.rb b/lib/caotral/linker/writer.rb
index c393023..203f44b 100644
--- a/lib/caotral/linker/writer.rb
+++ b/lib/caotral/linker/writer.rb
@@ -9,11 +9,11 @@ class Writer
       ALLOW_RELOCATION_TYPES = [R_X86_64_PC32, R_X86_64_PLT32].freeze
       RELOCATION_SECTION_NAMES = [".rela.text", ".rel.text"].freeze
       attr_reader :elf_obj, :output, :entry, :debug
-      def self.write!(elf_obj:, output:, entry: nil, debug: false)
-        new(elf_obj:, output:, entry:, debug:).write
+      def self.write!(elf_obj:, output:, entry: nil, debug: false, executable: true, shared: false)
+        new(elf_obj:, output:, entry:, debug:, shared:, executable:).write
       end
-      def initialize(elf_obj:, output:, entry: nil, debug: false)
-        @elf_obj, @output, @entry, @debug = elf_obj, output, entry, debug
+      def initialize(elf_obj:, output:, entry: nil, debug: false, executable: true, shared: false)
+        @elf_obj, @output, @entry, @debug, @executable, @shared = elf_obj, output, entry, debug, executable, shared
         @write_sections = write_order_sections
       end
       def write
diff --git a/sig/caotral/linker.rbs b/sig/caotral/linker.rbs
index d3971f9..ec8e2b5 100644
--- a/sig/caotral/linker.rbs
+++ b/sig/caotral/linker.rbs
@@ -3,15 +3,16 @@ class Caotral::Linker
   @output: String
   @linker: String
   @options: Array[String]
+  @executable: bool
   @shared: bool
   @debug: bool
 
-  def self.link!: (inputs: Array[String], ?output: String, ?linker: String, ?debug: bool, ?shared: bool) -> void
-  def initialize: (inputs: Array[String], ?output: String, ?linker: String, ?linker_options: Array[String], ?shared: bool, ?debug: bool) -> void
-  def link: (inputs: Array[String], ?output: String, ?shared: bool, ?debug: bool) -> void
+  def self.link!: (inputs: Array[String], ?output: String, ?linker: String, ?debug: bool, ?shared: bool, ?executable: bool) -> void
+  def initialize: (inputs: Array[String], ?output: String, ?linker: String, ?linker_options: Array[String], ?executable: bool, ?shared: bool, ?debug: bool) -> void
+  def link: (inputs: Array[String], ?output: String, ?shared: bool, ?debug: bool, ?executable: bool) -> void
 
   def link_command: (inputs: Array[String], ?output: String, ?shared: bool, ?debug: bool) -> String
   def libpath: () -> String
   def gcc_libpath: () -> String
-  def to_elf: (inputs: Array[String], ?output: String, ?debug: bool) -> String
+  def to_elf: (inputs: Array[String], ?output: String, ?debug: bool, ?shared: bool, ?executable: bool) -> String
 end
diff --git a/sig/caotral/linker/builder.rbs b/sig/caotral/linker/builder.rbs
index 0160a38..172e3b2 100644
--- a/sig/caotral/linker/builder.rbs
+++ b/sig/caotral/linker/builder.rbs
@@ -1,9 +1,13 @@
 class Caotral::Linker::Builder
-  @elf_obj: Caotral::Binary::ELF
+  @elf_objs: Array[Caotral::Binary::ELF]
   @symbols: Hash[Symbol, Set[String]]
+  @executable: bool
+  @debug: bool
+  @shared: bool
 
   attr_reader symbols: Hash[Symbol, Set[String]]
 
-  def initialize: (elf_obj: Caotral::Binary::ELF) -> void
+  def initialize: (elf_objs: Array[Caotral::Binary::ELF], ?executable: bool, ?debug: bool, ?shared: bool) -> void
+  def build: () -> Caotral::Binary::ELF
   def resolve_symbols: () -> Hash[Symbol, Set[String]]
 end
diff --git a/sig/caotral/linker/writer.rbs b/sig/caotral/linker/writer.rbs
index d47f1ef..87b6091 100644
--- a/sig/caotral/linker/writer.rbs
+++ b/sig/caotral/linker/writer.rbs
@@ -1,5 +1,5 @@
 class Caotral::Linker::Writer
-  def self.write!: (elf_obj: Caotral::Binary::ELF, output: String, ?entry: Integer, ?debug: bool) -> String
-  def initialize: (elf_obj: Caotral::Binary::ELF, output: String, ?entry: Integer, ?debug: bool) -> void
+  def self.write!: (elf_obj: Caotral::Binary::ELF, output: String, ?entry: Integer, ?debug: bool, ?executable: bool, ?shared: bool) -> String
+  def initialize: (elf_obj: Caotral::Binary::ELF, output: String, ?entry: Integer, ?debug: bool, ?executable: bool, ?shared: bool) -> void
   def write: () -> String
 end