diff --git a/examples/completions/test.sh b/examples/completions/test.sh
index 64d92ef8..2762dd07 100644
--- a/examples/completions/test.sh
+++ b/examples/completions/test.sh
@@ -2,7 +2,7 @@
 
 set -x
 
-bashly add comp function
+bashly add comp function --force
 bashly generate
 
 ### Try Me ###
diff --git a/lib/bashly.rb b/lib/bashly.rb
index 3a4b343f..cb56c08f 100644
--- a/lib/bashly.rb
+++ b/lib/bashly.rb
@@ -11,4 +11,5 @@
 requires 'bashly/exceptions'
 requires 'bashly/script/base'
 requires 'bashly/commands/base'
+requires 'bashly/library/base'
 requires 'bashly'
diff --git a/lib/bashly/commands/add.rb b/lib/bashly/commands/add.rb
index 6b596dd3..2c6ccd29 100644
--- a/lib/bashly/commands/add.rb
+++ b/lib/bashly/commands/add.rb
@@ -9,7 +9,7 @@ class Add < Base
       usage "bashly add colors [--force]"
       usage "bashly add yaml [--force]"
       usage "bashly add validations [--force]"
-      usage "bashly add comp FORMAT [OUTPUT]"
+      usage "bashly add comp FORMAT [OUTPUT --force]"
       usage "bashly add (-h|--help)"
 
       option "-f --force", "Overwrite existing files"
@@ -32,129 +32,81 @@ class Add < Base
       environment "BASHLY_SOURCE_DIR", "The path containing the bashly configuration and source files [default: src]"
 
       def strings_command
-        safe_copy asset("templates/strings.yml"), "#{Settings.source_dir}/bashly-strings.yml"
+        add_lib Library::Strings.new
       end
 
       def lib_command
-        safe_copy_file "sample_function.sh"
+        add_lib Library::Sample.new
       end
 
       def config_command
-        safe_copy_file "config.sh"
+        add_lib Library::Config.new
       end
 
       def colors_command
-        safe_copy_file "colors.sh"
+        add_lib Library::Colors.new
       end
 
       def yaml_command
-        safe_copy_file "yaml.sh"
+        add_lib Library::YAML.new
       end
 
       def validations_command
-        safe_copy_dir "validations"
+        add_lib Library::Validations.new
       end
 
       def comp_command
         format = args['FORMAT']
         output = args['OUTPUT']
-        
+
         case format
+        when "script"
+          path = output || "#{Settings.target_dir}/completions.bash"
+          add_lib Library::CompletionsScript.new(path)
+        
         when "function"
-          save_comp_function output
+          function = output || "send_completions"
+          path = "#{Settings.source_dir}/lib/#{function}.sh"
+          add_lib Library::CompletionsFunction.new(path, function: function)
+
         when "yaml"
-          save_comp_yaml output
-        when "script"
-          save_comp_script output
+          path = output || "#{Settings.target_dir}/completions.yml"
+          add_lib Library::CompletionsYAML.new(path)
+        
         else
           raise Error, "Unrecognized format: #{format}"
+
         end
 
       end
 
     private
 
-      def safe_copy_dir(dir)
-        Dir[asset("templates/lib/#{dir}/*.sh")].sort.each do |file|
-          safe_copy_file "#{dir}/#{File.basename file}"
+      def add_lib(handler)
+        files_created = 0
+        handler.files.each do |file|
+          created = safe_write file[:path], file[:content]
+          files_created += 1 if created
         end
+        message = handler.post_install_message
+        say "\n#{message}" if message and files_created > 0
       end
 
-      def safe_copy_file(file)
-        safe_copy asset("templates/lib/#{file}"), "#{Settings.source_dir}/lib/#{file}"
-      end
-
-      def safe_copy(source, target)
+      def safe_write(path, content)
         if !Dir.exist? Settings.source_dir
           raise InitError, "Directory !txtgrn!#{Settings.source_dir}!txtrst! does not exist\nRun !txtpur!bashly init!txtrst! first"
         end
 
-        if File.exist? target and !args['--force']
-          say "skipped !txtgrn!#{target}!txtrst! (exists)"
+        if File.exist? path and !args['--force']
+          say "skipped !txtgrn!#{path}!txtrst! (exists)"
+          false
+        
         else
-          deep_copy source, target
-          say "created !txtgrn!#{target}"
-        end
-      end
-
-      def deep_copy(source, target)
-        target_dir = File.dirname target
-        FileUtils.mkdir_p target_dir unless Dir.exist? target_dir
-        FileUtils.cp source, target
-      end
-
-      def config
-        @config ||= Config.new "#{Settings.source_dir}/bashly.yml"
-      end
-
-      def command
-        @command ||= Script::Command.new config
-      end
-
-      def completions
-        @completions ||= command.completion_data
-      end
-
-      def completions_script
-        @completions_script ||= command.completion_script
-      end
-
-      def completions_function
-        @completions_function ||= command.completion_function
-      end
-
-      def save_comp_yaml(filename = nil)
-        filename ||= "#{Settings.target_dir}/completions.yml"
-        File.write filename, completions.to_yaml
-        say "created !txtgrn!#{filename}"
-        say ""
-        say "This file can be converted to a completions script using the !txtgrn!completely!txtrst! gem."
-      end
-
-      def save_comp_script(filename = nil)
-        filename ||= "#{Settings.target_dir}/completions.bash"
-        File.write filename, completions_script
-        say "created !txtgrn!#{filename}"
-        say ""
-        say "In order to enable completions, run:"
-        say ""
-        say "  !txtpur!$ source #{filename}"
-      end
-
-      def save_comp_function(name = nil)
-        name ||= "send_completions"
-        target_dir = "#{Settings.source_dir}/lib"
-        filename = "#{target_dir}/#{name}.sh"
+          File.deep_write path, content
+          say "created !txtgrn!#{path}"
+          true
         
-        FileUtils.mkdir_p target_dir unless Dir.exist? target_dir
-        File.write filename, completions_function
-
-        say "created !txtgrn!#{filename}"
-        say ""
-        say "In order to use it in your script, create a command or a flag (for example: !txtgrn!#{command.name} completions!txtrst! or !txtgrn!#{command.name} --completions!txtrst!) that calls the !txtgrn!#{name}!txtrst! function."
-        say "Your users can then run something like this to enable completions:"
-        say ""
-        say "  !txtpur!$ eval \"$(#{command.name} completions)\""
+        end
       end
 
     end
diff --git a/lib/bashly/concerns/asset_helper.rb b/lib/bashly/concerns/asset_helper.rb
index 28cb559b..f5ff4409 100644
--- a/lib/bashly/concerns/asset_helper.rb
+++ b/lib/bashly/concerns/asset_helper.rb
@@ -3,5 +3,9 @@ module AssetHelper
     def asset(path)
       File.expand_path "../#{path}", __dir__
     end
+
+    def asset_content(path)
+      File.read asset(path)
+    end
   end
 end
\ No newline at end of file
diff --git a/lib/bashly/extensions/file.rb b/lib/bashly/extensions/file.rb
new file mode 100644
index 00000000..fa90dd64
--- /dev/null
+++ b/lib/bashly/extensions/file.rb
@@ -0,0 +1,9 @@
+require "fileutils"
+
+class File
+  def self.deep_write(file, content)
+    dir = File.dirname file
+    FileUtils.mkdir_p dir unless Dir.exist? dir
+    File.write file, content
+  end
+end
diff --git a/lib/bashly/library/base.rb b/lib/bashly/library/base.rb
new file mode 100644
index 00000000..8a13c33a
--- /dev/null
+++ b/lib/bashly/library/base.rb
@@ -0,0 +1,57 @@
+module Bashly
+  module Library
+    class Base
+      include AssetHelper
+
+      attr_reader :target_path, :options
+
+      def initialize(target_path = nil, options = nil)
+        @target_path = target_path || Settings.source_dir
+        @options = options || {}
+      end
+
+      def files
+        case content
+        when String then content_from_string content
+        when Hash then [content]
+        else content
+        end
+      end
+
+      def post_install_message
+        nil
+      end
+
+      def content
+        raise NotImplementedError, "Please implement either #content"
+      end
+
+    private
+
+      def content_from_string(string)
+        if File.directory? asset("templates/lib/#{string}")
+          content_for_dir string
+        else
+          [content_for_file(string)]
+        end
+      end
+
+      def content_for_file(file)
+        {
+          path: "#{target_path}/lib/#{file}",
+          content: asset_content("templates/lib/#{file}")
+        }
+      end
+
+      def content_for_dir(dir)
+        Dir[asset("templates/lib/#{dir}/*.sh")].sort.map do |file|
+          {
+            path: "#{target_path}/lib/#{dir}/#{File.basename file}",
+            content: File.read(file)
+          }
+        end
+      end
+
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/bashly/library/colors.rb b/lib/bashly/library/colors.rb
new file mode 100644
index 00000000..6b26ff98
--- /dev/null
+++ b/lib/bashly/library/colors.rb
@@ -0,0 +1,9 @@
+module Bashly
+  module Library
+    class Colors < Base
+      def content
+        "colors.sh"
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/bashly/library/completions.rb b/lib/bashly/library/completions.rb
new file mode 100644
index 00000000..5c989b9a
--- /dev/null
+++ b/lib/bashly/library/completions.rb
@@ -0,0 +1,28 @@
+module Bashly
+  module Library
+    class Completions < Base
+      def content
+        { path: target_path, content: file_content }
+      end
+
+      def file_content
+        raise NotImplementedError, "Please implement #file_content"
+      end
+
+    protected
+
+      def completions
+        @completions ||= command.completion_data
+      end
+
+      def config
+        @config ||= Bashly::Config.new "#{Settings.source_dir}/bashly.yml"
+      end
+
+      def command
+        @command ||= Script::Command.new config
+      end
+   
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/bashly/library/completions_function.rb b/lib/bashly/library/completions_function.rb
new file mode 100644
index 00000000..57bdacf6
--- /dev/null
+++ b/lib/bashly/library/completions_function.rb
@@ -0,0 +1,23 @@
+module Bashly
+  module Library
+    class CompletionsFunction < Completions
+      def file_content
+        command.completion_function function_name
+      end
+
+      def post_install_message
+        <<~EOF
+          In order to enable completions in your script, create a command or a flag (for example: !txtgrn!#{command.name} completions!txtrst! or !txtgrn!#{command.name} --completions!txtrst!) that calls the !txtgrn!#{function_name}!txtrst! function.
+
+          Your users can then run something like this to enable completions:
+
+            !txtpur!$ eval \"$(#{command.name} completions)\"
+        EOF
+      end
+
+      def function_name
+        options[:function]
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/bashly/library/completions_script.rb b/lib/bashly/library/completions_script.rb
new file mode 100644
index 00000000..07d608a8
--- /dev/null
+++ b/lib/bashly/library/completions_script.rb
@@ -0,0 +1,17 @@
+module Bashly
+  module Library
+    class CompletionsScript < Completions
+      def file_content
+        command.completion_script
+      end
+
+      def post_install_message
+        <<~EOF
+          In order to enable completions, run:
+
+            !txtpur!$ source #{target_path}
+        EOF
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/bashly/library/completions_yaml.rb b/lib/bashly/library/completions_yaml.rb
new file mode 100644
index 00000000..adaddf36
--- /dev/null
+++ b/lib/bashly/library/completions_yaml.rb
@@ -0,0 +1,15 @@
+module Bashly
+  module Library
+    class CompletionsYAML < Completions
+      def file_content
+        completions.to_yaml
+      end
+
+      def post_install_message
+        <<~EOF
+          This file can be converted to a completions script using the !txtgrn!completely!txtrst! gem.
+        EOF
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/bashly/library/config.rb b/lib/bashly/library/config.rb
new file mode 100644
index 00000000..1bfe5c47
--- /dev/null
+++ b/lib/bashly/library/config.rb
@@ -0,0 +1,9 @@
+module Bashly
+  module Library
+    class Config < Base
+      def content
+        "config.sh"
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/bashly/library/sample.rb b/lib/bashly/library/sample.rb
new file mode 100644
index 00000000..2dae8c34
--- /dev/null
+++ b/lib/bashly/library/sample.rb
@@ -0,0 +1,9 @@
+module Bashly
+  module Library
+    class Sample < Base
+      def content
+        "sample_function.sh"
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/bashly/library/strings.rb b/lib/bashly/library/strings.rb
new file mode 100644
index 00000000..6e673fbd
--- /dev/null
+++ b/lib/bashly/library/strings.rb
@@ -0,0 +1,12 @@
+module Bashly
+  module Library
+    class Strings < Base
+      def content
+        {
+          path: "#{target_path}/bashly-strings.yml",
+          content: asset_content("templates/strings.yml")
+        }
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/bashly/library/validations.rb b/lib/bashly/library/validations.rb
new file mode 100644
index 00000000..4b370f95
--- /dev/null
+++ b/lib/bashly/library/validations.rb
@@ -0,0 +1,9 @@
+module Bashly
+  module Library
+    class Validations < Base
+      def content
+        "validations"
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/bashly/library/yaml.rb b/lib/bashly/library/yaml.rb
new file mode 100644
index 00000000..a978f140
--- /dev/null
+++ b/lib/bashly/library/yaml.rb
@@ -0,0 +1,9 @@
+module Bashly
+  module Library
+    class YAML < Base
+      def content
+        "yaml.sh"
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/spec/approvals/cli/add/comp-function b/spec/approvals/cli/add/comp-function
index 7e034b8d..fb2ea773 100644
--- a/spec/approvals/cli/add/comp-function
+++ b/spec/approvals/cli/add/comp-function
@@ -1,6 +1,8 @@
 created spec/tmp/src/lib/send_completions.sh
 
-In order to use it in your script, create a command or a flag (for example: cli completions or cli --completions) that calls the send_completions function.
+In order to enable completions in your script, create a command or a flag (for example: cli completions or cli --completions) that calls the send_completions function.
+
 Your users can then run something like this to enable completions:
 
   $ eval "$(cli completions)"
+
diff --git a/spec/approvals/cli/add/comp-script b/spec/approvals/cli/add/comp-script
index f539fd6e..e5d1b545 100644
--- a/spec/approvals/cli/add/comp-script
+++ b/spec/approvals/cli/add/comp-script
@@ -3,3 +3,4 @@ created spec/tmp/completions.bash
 In order to enable completions, run:
 
   $ source spec/tmp/completions.bash
+
diff --git a/spec/approvals/cli/add/comp-yaml b/spec/approvals/cli/add/comp-yaml
index fbd35516..25930fcd 100644
--- a/spec/approvals/cli/add/comp-yaml
+++ b/spec/approvals/cli/add/comp-yaml
@@ -1,3 +1,4 @@
 created spec/tmp/completions.yml
 
 This file can be converted to a completions script using the completely gem.
+
diff --git a/spec/approvals/cli/add/help b/spec/approvals/cli/add/help
index e47669bf..c4bbed62 100644
--- a/spec/approvals/cli/add/help
+++ b/spec/approvals/cli/add/help
@@ -7,7 +7,7 @@ Usage:
   bashly add colors [--force]
   bashly add yaml [--force]
   bashly add validations [--force]
-  bashly add comp FORMAT [OUTPUT]
+  bashly add comp FORMAT [OUTPUT --force]
   bashly add (-h|--help)
 
 Commands:
diff --git a/spec/approvals/cli/generate/usage b/spec/approvals/cli/generate/usage
index 4cbabbf3..152f0f0e 100644
--- a/spec/approvals/cli/generate/usage
+++ b/spec/approvals/cli/generate/usage
@@ -5,5 +5,5 @@ Usage:
   bashly add colors [--force]
   bashly add yaml [--force]
   bashly add validations [--force]
-  bashly add comp FORMAT [OUTPUT]
+  bashly add comp FORMAT [OUTPUT --force]
   bashly add (-h|--help)
diff --git a/spec/approvals/examples/completions b/spec/approvals/examples/completions
index abea0118..97beb800 100644
--- a/spec/approvals/examples/completions
+++ b/spec/approvals/examples/completions
@@ -1,10 +1,12 @@
-+ bashly add comp function
++ bashly add comp function --force
 created src/lib/send_completions.sh
 
-In order to use it in your script, create a command or a flag (for example: cli completions or cli --completions) that calls the send_completions function.
+In order to enable completions in your script, create a command or a flag (for example: cli completions or cli --completions) that calls the send_completions function.
+
 Your users can then run something like this to enable completions:
 
   $ eval "$(cli completions)"
+
 + bashly generate
 creating user files in src
 skipped src/initialize.sh (exists)
diff --git a/spec/approvals/library/base/dir b/spec/approvals/library/base/dir
new file mode 100644
index 00000000..953e5490
--- /dev/null
+++ b/spec/approvals/library/base/dir
@@ -0,0 +1,21 @@
+---
+- :path: spec/tmp/src/lib/validations/validate_dir_exists.sh
+  :content: |
+    validate_dir_exists() {
+      [[ -d "$1" ]] || echo "must be an existing directory"
+    }
+- :path: spec/tmp/src/lib/validations/validate_file_exists.sh
+  :content: |
+    validate_file_exists() {
+      [[ -f "$1" ]] || echo "must be an existing file"
+    }
+- :path: spec/tmp/src/lib/validations/validate_integer.sh
+  :content: |-
+    validate_integer() {
+      [[ "$1" =~ ^[0-9]+$ ]] || echo "must be an integer"
+    }
+- :path: spec/tmp/src/lib/validations/validate_not_empty.sh
+  :content: |
+    validate_not_empty() {
+      [[ -z "$1" ]] && echo "must not be empty"
+    }
diff --git a/spec/bashly/concerns/asset_helper_spec.rb b/spec/bashly/concerns/asset_helper_spec.rb
new file mode 100644
index 00000000..9677cf48
--- /dev/null
+++ b/spec/bashly/concerns/asset_helper_spec.rb
@@ -0,0 +1,18 @@
+require 'spec_helper'
+
+describe AssetHelper do
+  subject { Class.new { include AssetHelper }.new }
+  let(:path) { "version.rb" }
+
+  describe '#asset' do
+    it "returns a path to any file in the source tree" do
+      expect(subject.asset path).to end_with "lib/bashly/#{path}"
+    end
+  end
+
+  describe '#asset_content' do
+    it "returns the contents of any file in the source tree" do
+      expect(subject.asset_content path).to eq File.read(subject.asset path)
+    end
+  end  
+end
diff --git a/spec/bashly/extensions/file_spec.rb b/spec/bashly/extensions/file_spec.rb
new file mode 100644
index 00000000..51fe2bde
--- /dev/null
+++ b/spec/bashly/extensions/file_spec.rb
@@ -0,0 +1,11 @@
+require 'spec_helper'
+
+describe File do
+  describe '::deep_write' do
+    it "creates parent directories and writes a file" do
+      expect(FileUtils).to receive(:mkdir_p).with('some/path')
+      expect(File).to receive(:write).with('some/path/file.txt', 'text')
+      File.deep_write 'some/path/file.txt', 'text'
+    end
+  end
+end
diff --git a/spec/bashly/library/base_spec.rb b/spec/bashly/library/base_spec.rb
new file mode 100644
index 00000000..01488845
--- /dev/null
+++ b/spec/bashly/library/base_spec.rb
@@ -0,0 +1,83 @@
+require 'spec_helper'
+
+describe Library::Base do
+  let(:lib_dir) { 'lib/bashly/templates/lib' }
+
+  describe '#content' do
+    it "raises a NotImplementedError" do
+      expect { subject.content }.to raise_error(NotImplementedError)
+    end
+  end
+
+  describe '#files' do
+    it "raises a NotImplementedError" do
+      expect { subject.files }.to raise_error(NotImplementedError)
+    end
+
+    context "when #content is a string representing a lib/file" do
+      subject do
+        Class.new(described_class) { def content; "colors.sh"; end }.new
+      end
+      
+      it "returns an array of hashes" do
+        expect(subject.files).to be_an Array
+        expect(subject.files.first).to be_a Hash
+      end
+
+      it "returns the content and target paths of the library files" do
+        matter = subject.files.first
+        expect(matter.keys).to eq [:path, :content]
+        expect(matter[:path]).to eq "#{Settings.target_dir}/src/lib/#{subject.content}"
+        expect(matter[:content]).to eq File.read("#{lib_dir}/#{subject.content}")
+      end
+    end
+
+    context "when #content is a string representing a lib/dir" do
+      subject do
+        Class.new(described_class) { def content; "validations"; end }.new
+      end
+      
+      it "returns an array of hashes" do
+        expect(subject.files).to be_an Array
+        expect(subject.files.first).to be_a Hash
+      end
+      
+      it "returns an array as big as the library folder" do
+        expect(subject.files.count).to be > 1
+        expect(subject.files.count).to eq Dir["#{lib_dir}/#{subject.content}/*.sh"].count
+      end
+
+      it "returns the content and target paths of the library files" do
+        expect(subject.files.to_yaml).to match_approval 'library/base/dir'
+      end
+    end
+
+    context "when #content is a hash" do
+      subject do
+        Class.new(described_class) { def content; { some: 'hash' }; end }.new
+      end
+      
+      it "returns an array with the hash as its first and only element" do
+        expect(subject.files).to be_an Array
+        expect(subject.files.count).to eq 1
+        expect(subject.files.first).to eq subject.content
+      end
+    end
+
+    context "when #content is something else" do
+      subject do
+        Class.new(described_class) { def content; ["something else"]; end }.new
+      end
+      
+      it "returns it as is" do
+        expect(subject.files).to eq subject.content
+      end
+    end
+  end
+
+  describe '#post_install_message' do
+    it "returns nil" do
+      expect(subject.post_install_message).to be_nil
+    end
+  end
+end
diff --git a/spec/bashly/library/completions_spec.rb b/spec/bashly/library/completions_spec.rb
new file mode 100644
index 00000000..a13cdff8
--- /dev/null
+++ b/spec/bashly/library/completions_spec.rb
@@ -0,0 +1,9 @@
+require 'spec_helper'
+
+describe Library::Completions do
+  describe '#file_content' do
+    it "raises a NotImplementedError" do
+      expect { subject.content }.to raise_error(NotImplementedError)
+    end
+  end
+end