diff --git a/bin/commit-info b/bin/commit-info
new file mode 100755
index 0000000..c70e9c5
--- /dev/null
+++ b/bin/commit-info
@@ -0,0 +1,52 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+require 'optparse'
+
+require_relative '../lib/commit_info'
+require_relative '../lib/errors'
+require_relative '../lib/log'
+
+options = {
+  repo: 'emacs-mirror/emacs',
+  output: File.expand_path('../tarballs', __dir__),
+  log_level: :info
+}
+
+OptionParser.new do |opts|
+  opts.banner = <<~TXT
+    Usage: ./commit-info [options] <branch/tag/sha>
+
+    Fetch commit info of given GitHub repository branch, tag, or SHA.
+
+    Options:
+  TXT
+
+  opts.on('-r', '--repo STRING',
+          "GitHub repository (default: #{options[:repo]})") do |v|
+    options[:repo] = v
+  end
+
+  opts.on('-o', '--output DIR', 'Directory to save tarball in ' \
+          "(default: #{options[:output]})") do |v|
+    options[:output] = v
+  end
+
+  opts.on('-l', '--log-level LEVEL', 'Log level ' \
+          "(default: #{options[:log_level]})") do |v|
+    options[:log_level] = v.to_sym
+  end
+end.parse!
+
+begin
+  logger = Log.new('commit-info', options[:log_level])
+  commit = CommitInfo.new(
+    ref: ARGV[0],
+    repo: options[:repo],
+    logger: logger
+  ).perform
+
+  puts commit.to_yaml
+rescue Error => e
+  handle_error(e)
+end
diff --git a/bin/download-tarball b/bin/download-tarball
index c61ac97..f067c2a 100755
--- a/bin/download-tarball
+++ b/bin/download-tarball
@@ -5,6 +5,7 @@ require 'optparse'
 
 require_relative '../lib/download_tarball'
 require_relative '../lib/errors'
+require_relative '../lib/log'
 
 options = {
   repo: 'emacs-mirror/emacs',
@@ -38,7 +39,13 @@ OptionParser.new do |opts|
 end.parse!
 
 begin
-  tarball = DownloadTarball.new(ref: ARGV[0], **options).perform
+  logger = Log.new('download-tarball', options[:log_level])
+  tarball = DownloadTarball.new(
+    ref: ARGV[0],
+    repo: options[:repo],
+    output: options[:output],
+    logger: logger
+  ).perform
 
   puts tarball.to_yaml
 rescue Error => e
diff --git a/lib/base_action.rb b/lib/base_action.rb
new file mode 100644
index 0000000..909e151
--- /dev/null
+++ b/lib/base_action.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+require_relative './common'
+require_relative './output'
+
+class BaseAction
+  include Common
+  include Output
+end
diff --git a/lib/commit.rb b/lib/commit.rb
index ac608e3..adf9ce2 100644
--- a/lib/commit.rb
+++ b/lib/commit.rb
@@ -1,14 +1,27 @@
 # frozen_string_literal: true
 
+require 'json'
+require 'time'
 require 'yaml'
 
+require_relative './errors'
+require_relative './common'
+
 class Commit
+  include Common
+
+  attr_reader :repo
+  attr_reader :ref
+  attr_reader :message
   attr_reader :sha
   attr_reader :time
 
-  def initialize(sha:, time:)
+  def initialize(sha:, time:, repo: nil, ref: nil, message: nil)
     @sha = sha
     @time = time
+    @repo = repo
+    @ref = ref
+    @message = message
   end
 
   def sha_short
@@ -17,9 +30,13 @@ class Commit
 
   def to_hash
     {
+      'repo' => repo,
+      'ref' => ref,
       'sha' => sha,
       'sha_short' => sha_short,
-      'time' => time
+      'time' => time.utc,
+      'timestamp' => time.utc.to_i,
+      'message' => message
     }
   end
 
diff --git a/lib/commit_info.rb b/lib/commit_info.rb
new file mode 100644
index 0000000..464dcf0
--- /dev/null
+++ b/lib/commit_info.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+require_relative './base_action'
+require_relative './commit'
+
+class CommitInfo < BaseAction
+  COMMIT_URL = 'https://api.github.com/repos/%s/commits/%s'
+
+  attr_reader :ref
+  attr_reader :repo
+  attr_reader :logger
+
+  def initialize(ref:, repo:, logger:)
+    @ref = ref
+    @repo = repo
+    @logger = logger
+
+    err 'branch/tag/sha argument cannot be empty' if ref.nil? || ref.empty?
+  end
+
+  def perform
+    info "Fetching info for git ref: #{ref}"
+
+    url = format(COMMIT_URL, repo, ref)
+    commit_json = http_get(url)
+
+    err "Failed to get commit info about: #{ref}" if commit_json.nil?
+
+    parsed = JSON.parse(commit_json)
+    commit = Commit.new(
+      repo: repo,
+      ref: ref,
+      sha: parsed&.dig('sha'),
+      message: parsed&.dig('commit', 'message'),
+      time: Time.parse(parsed&.dig('commit', 'committer', 'date')).utc
+    )
+
+    err 'Failed to get commit SHA' if commit.sha.nil? || commit.sha.empty?
+    err 'Failed to get commit time' if commit.time.nil?
+
+    commit
+  end
+end
diff --git a/lib/common.rb b/lib/common.rb
index e25b463..bf17160 100644
--- a/lib/common.rb
+++ b/lib/common.rb
@@ -5,6 +5,10 @@ require 'net/http'
 module Common
   private
 
+  def self.included(base)
+    base.extend(self)
+  end
+
   def run_cmd(*args)
     info "executing: #{args.join(' ')}"
     system(*args) || err("Exit code: #{$CHILD_STATUS.exitstatus}")
diff --git a/lib/download_tarball.rb b/lib/download_tarball.rb
index ae37824..1bae8fb 100644
--- a/lib/download_tarball.rb
+++ b/lib/download_tarball.rb
@@ -4,30 +4,24 @@ require 'fileutils'
 require 'json'
 require 'time'
 
-require_relative './common'
-require_relative './commit'
-require_relative './output'
+require_relative './base_action'
+
+require_relative './commit_info'
 require_relative './tarball'
 
-class DownloadTarball
-  include Common
-  include Output
-
-  logger_name 'download-tarball'
-
+class DownloadTarball < BaseAction
   TARBALL_URL = 'https://github.com/%s/tarball/%s'
-  COMMIT_URL = 'https://api.github.com/repos/%s/commits/%s'
 
   attr_reader :ref
   attr_reader :repo
   attr_reader :output
-  attr_reader :log_level
+  attr_reader :logger
 
-  def initialize(ref:, repo:, output:, log_level:)
+  def initialize(ref:, repo:, output:, logger:)
     @ref = ref
     @repo = repo
     @output = output
-    @log_level = log_level
+    @logger = logger
 
     err 'branch/tag/sha argument cannot be empty' if ref.nil? || ref.empty?
   end
@@ -62,22 +56,6 @@ class DownloadTarball
   end
 
   def commit
-    return @commit if @commit
-
-    info "Fetching info for git ref: #{ref}"
-    url = format(COMMIT_URL, repo, ref)
-    commit_json = http_get(url)
-    err "Failed to get commit info about: #{ref}" if commit_json.nil?
-
-    parsed = JSON.parse(commit_json)
-    commit = Commit.new(
-      sha: parsed&.dig('sha'),
-      time: Time.parse(parsed&.dig('commit', 'committer', 'date'))
-    )
-
-    err 'Failed to get commit SHA' if commit.sha.nil? || commit.sha.empty?
-    err 'Failed to get commit time' if commit.time.nil?
-
-    @commit = commit
+    @commit ||= CommitInfo.new(ref: ref, repo: repo, logger: logger).perform
   end
 end
diff --git a/lib/errors.rb b/lib/errors.rb
index 5af62fd..02410a6 100644
--- a/lib/errors.rb
+++ b/lib/errors.rb
@@ -6,3 +6,7 @@ def handle_error(err)
 end
 
 class Error < StandardError; end
+
+class CommitNotFound < Error; end
+class NoCommitSHA < Error; end
+class NoCommitTime < Error; end
diff --git a/lib/log.rb b/lib/log.rb
new file mode 100644
index 0000000..31d1e97
--- /dev/null
+++ b/lib/log.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+class Log
+  extend Forwardable
+
+  attr_reader :name
+  attr_reader :level
+
+  def initialize(name, level = :info)
+    @name = name
+    @level = level
+  end
+
+  def_delegators :logger, :debug, :info, :warn, :error, :fatal, :unkonwn
+
+  private
+
+  def logger
+    @logger ||= Logger.new($stderr).tap do |l|
+      l.progname = name
+      l.level = level
+      l.formatter = formatter
+    end
+  end
+
+  def formatter
+    proc do |severity, _datetime, progname, msg|
+      "==> [#{progname}] #{severity}: #{msg}\n"
+    end
+  end
+end
diff --git a/lib/output.rb b/lib/output.rb
index 04f227c..571f478 100644
--- a/lib/output.rb
+++ b/lib/output.rb
@@ -25,25 +25,4 @@ module Output
   def err(msg = nil)
     raise Error, msg
   end
-
-  private
-
-  # override to set custom log level
-  def log_level
-    :info
-  end
-
-  def logger
-    @logger ||= Logger.new($stderr).tap do |l|
-      l.progname = self.class.logger_name
-      l.level = log_level
-      l.formatter = log_formatter
-    end
-  end
-
-  def log_formatter
-    proc do |severity, _datetime, progname, msg|
-      "==> [#{progname}] #{severity}: #{msg}\n"
-    end
-  end
 end