diff --git a/lib/vaporware/compiler.rb b/lib/vaporware/compiler.rb
index bb270a6..417d772 100644
--- a/lib/vaporware/compiler.rb
+++ b/lib/vaporware/compiler.rb
@@ -9,12 +9,30 @@ def self.compile(source, compiler: "gcc", dest: "tmp", debug: false, compiler_op
       _precompile = "#{dest}.s"
       s = new(source, _precompile: _precompile, debug:, shared:)
       s.compile(compiler:, compiler_options:)
+      obj = s.assemble(input: _precompile, compmiler:, compiler_options:, debug:)
+      s.link(input: obj,link_options:)
     end
 
     def initialize(source, _precompile: "tmp.s", debug: false, shared: false)
       @generator = Vaporware::Compiler::Generator.new(source, precompile: _precompile, debug:, shared:)
     end
 
+    def assemble(input: precompile, output: File.basename(precompile, ".*") + ".o", compiler: "gcc", compiler_options: ["-O0"], debug: false)
+      base_name = File.basename(input, ".*")
+      name = shared ? "lib#{base_name}.so" : base_name
+      if compiler == "gcc"
+        compile_commands = [compiler, *compiler_options, "-o", name, input].compact
+        call_compiler(compile_commands)
+      else
+        Vaporware::Compiler::Assemble.assemble!(input, name)
+      end
+
+      File.delete(input) unless debug
+      nil
+    end
+
+    def call_compiler(compile_commands) = IO.popen(compile_commands).close
+
     def compile(compiler: "gcc", compiler_options: ["-O0"])
       @generator.register_var_and_method(@generator.ast)
 
diff --git a/lib/vaporware/compiler/assemble.rb b/lib/vaporware/compiler/assemble.rb
index ea28ca1..ff95099 100644
--- a/lib/vaporware/compiler/assemble.rb
+++ b/lib/vaporware/compiler/assemble.rb
@@ -1,17 +1,116 @@
 # frozen_string_literal: true
 
 module Vaporware
-  class Compiler::Assemble
-    attr_reader :input, :output
-    def self.compile!(input, output = File.basename(input, ".*")) = new(input, output).compile
+  class Compiler
+    class Assemble
+      EXEC_ELF_HEADER = %w(
+        7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00
+        02 00 3e 00 01 00 00 00 78 00 40 00 00 00 00 00
+        40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+        00 00 00 00 40 00 38 00 01 00 40 00 00 00 00 00
+      ).map { _1.to_i(16) }.pack("C*")
 
-    def initialize(input, output = File.basename(input, ".*"))
-      @input, @output = input, output
-      @target_file = File.open(output, "wb")
-    end
+      SHARED_ELF_HEADER = %w(
+        7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00
+        03 00 3e 00 01 00 00 00 78 00 40 00 00 00 00 00
+        40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+        00 00 00 00 40 00 38 00 01 00 40 00 00 00 00 00
+      ).map { _1.to_i(16) }.pack("C*")
+
+      PROGRAM_ELF_HEADER = %w(
+        01 00 00 00 07 00 00 00 00 00 00 00 00 00 00 00
+        00 00 40 00 00 00 00 00 00 00 40 00 00 00 00 00
+        90 00 00 00 00 00 00 00 90 00 00 00 00 00 00 00
+        00 00 20 00 00 00 00 00
+      ).map { _1.to_i(16) }.pack("C*")
+
+      PREFIX = {
+        REX_W: "48",
+      }
+
+      REGISTER_CODE = {
+        RAX: 0,
+        RDI: 7,
+      }
+
+      attr_reader :input, :output
+      def self.assemble!(input, output = File.basename(input, ".*")) = new(input, output).assemble
+
+      def initialize(input, output = File.basename(input, ".*") + ".o")
+        @input, @output = input, output
+        @target_file = File.open(output, "wb")
+      end
+
+      def assemble(assemble_command: "as", assemble_options: [], input: @input, f: @target_file)
+        f.write(EXEC_ELF_HEADER)
+        f.write(PROGRAM_ELF_HEADER)
+        read = { main: false }
+        File.open(input, "r") do |r|
+          r.each_line do |line|
+            read[:main] = /main:/.match(line) unless read[:main]
+            next unless read[:main] && !/main:/.match(line)
+            op, *args = line.split(/\s+/).reject{ _1 == "" }.map { _1.gsub(/,/, "") }
+            p [op, args]
+            opes = opecode(op, args)
+            f.write(opes.pack("C*"))
+          end
+        end
+        f.close
+        f.path
+      end
+
+      private
+
+      def opecode(op, args)
+        case op
+        when "push"
+          push(args).map { _1.to_i(16) }
+        when "mov", "sub", "add"
+          [PREFIX[:REX_W], *mov_sub(op, *args)].map{ _1.to_i(16) }
+        when "pop"
+          pop(args)
+        end
+      end
+
+      def mov_sub(*argments)
+        _op, *args = argments
+        args.map { reg(_1) }
+      end
+
+      def push(args)
+        case args
+        in ["rbp"] | ["rdi"]
+          [0x50 + 5].map { _1.to_s(16) }
+        else
+          ["6a", *args]
+        end
+      end
+
+      def pop(args)
+        case args
+        in ["rax"] | ["rdi"]
+          [0x58 + REGISTER_CODE[args.first.upcase.to_sym]]
+        end
+      end
 
-    def compile(compile_options = [])
-      self
+      def reg(r)
+        case r
+        in "rsp"
+          "89"
+        in "rbp"
+          "5e"
+        in "rax"
+          "29"
+        in "rdi"
+          "f8"
+        in /\d+/
+          r
+        in "mov"
+          "89"
+        in "sub"
+          "83"
+        end
+      end
     end
   end
 end
diff --git a/lib/vaporware/compiler/generator.rb b/lib/vaporware/compiler/generator.rb
index 19f17d0..d620414 100644
--- a/lib/vaporware/compiler/generator.rb
+++ b/lib/vaporware/compiler/generator.rb
@@ -35,7 +35,7 @@ def to_elf(input: precompile, compiler: "gcc", compiler_options: ["-O0"], debug:
         base_name = File.basename(input, ".*")
         name = shared ? "lib#{base_name}.so" : base_name
         if compiler.nil?
-          Vaporware::Compiler::Assemble.compile!(name, input)
+          Vaporware::Compiler::Assemble.assemble!(name, input)
         else
           compile_commands = [compiler, *compiler_options, "-o", name, input].compact
           call_compiler(compile_commands)
diff --git a/sig/vaporware/compiler.rbs b/sig/vaporware/compiler.rbs
index 59e7d9c..e02a603 100644
--- a/sig/vaporware/compiler.rbs
+++ b/sig/vaporware/compiler.rbs
@@ -5,6 +5,8 @@ class Vaporware::Compiler
 
   @generator: Vaporware::Compiler::Generator
   # instance methods
+  def assemble: (?output: String, ?compiler: String, ?compiler_options: Array[String]) -> void
+  def link: (?output: String, ?linker: String, ?linker_options: Array[String]) -> void
   def compile: (?compiler: String, ?compiler_options: Array[String]) -> void
 end
 
diff --git a/sig/vaporware/compiler/assemble.rbs b/sig/vaporware/compiler/assemble.rbs
new file mode 100644
index 0000000..16e7d9d
--- /dev/null
+++ b/sig/vaporware/compiler/assemble.rbs
@@ -0,0 +1,9 @@
+class Vaporware::Compiler::Assemble
+  attr_reader input: String
+  attr_reader output: String
+
+  @target_file: File
+
+  def initialize: (String, String) -> void
+  def compile: (?compiler_options: Array[String]) -> void
+end
diff --git a/sig/vaporware/compiler/generator.rbs b/sig/vaporware/compiler/generator.rbs
index 3af1e8c..954a00d 100644
--- a/sig/vaporware/compiler/generator.rbs
+++ b/sig/vaporware/compiler/generator.rbs
@@ -22,7 +22,6 @@ class Vaporware::Compiler::Generator
 
   # instance private methods
   def already_build_methods?: -> bool
-  def call_compiler: (?output: String, ?compiler: String, ?compiler_options: Array[String]) -> void
   def call_method: (RubyVM::AbstractSyntaxTree::Node, File, bool) -> void
   def comp: (String, File) -> void
   def compile_shared_option: () -> Array[String]