diff --git a/Library/Homebrew/cli/args.rbi b/Library/Homebrew/cli/args.rbi
index 32b1cd8e6e..e0aaee87f1 100644
--- a/Library/Homebrew/cli/args.rbi
+++ b/Library/Homebrew/cli/args.rbi
@@ -300,6 +300,15 @@ module Homebrew
       sig { returns(T.nilable(String)) }
       def screen_saverdir; end
 
+      sig { returns(T::Array[String])}
+      def repositories; end
+
+      sig { returns(T.nilable(String)) }
+      def from; end
+
+      sig { returns(T.nilable(String)) }
+      def to; end
+
       sig { returns(T.nilable(T::Array[String])) }
       def groups; end
 
diff --git a/Library/Homebrew/dev-cmd/contributions.rb b/Library/Homebrew/dev-cmd/contributions.rb
new file mode 100755
index 0000000000..946c40b8f1
--- /dev/null
+++ b/Library/Homebrew/dev-cmd/contributions.rb
@@ -0,0 +1,109 @@
+# typed: true
+# frozen_string_literal: true
+
+require "cli/parser"
+
+module Homebrew
+  extend T::Sig
+
+  module_function
+
+  SUPPORTED_REPOS = [
+    %w[brew core cask],
+    OFFICIAL_CMD_TAPS.keys.map { |t| t.delete_prefix("homebrew/") },
+    OFFICIAL_CASK_TAPS.reject { |t| t == "cask" },
+  ].flatten.freeze
+
+  sig { returns(CLI::Parser) }
+  def contributions_args
+    Homebrew::CLI::Parser.new do
+      usage_banner "`contributions` <email|name> [<--repositories>`=`]"
+      description <<~EOS
+        Contributions to Homebrew repos for a user.
+
+        The first argument is a name (e.g. "BrewTestBot") or an email address (e.g. "brewtestbot@brew.sh").
+      EOS
+
+      comma_array "--repositories",
+                  description: "Specify a comma-separated (no spaces) list of repositories to search. " \
+                               "Supported repositories: #{SUPPORTED_REPOS.map { |t| "`#{t}`" }.to_sentence}." \
+                               "Omitting this flag, or specifying `--repositories=all`, will search all repositories."
+      flag "--from=",
+           description: "Date (ISO-8601 format) to start searching contributions."
+
+      flag "--to=",
+           description: "Date (ISO-8601 format) to stop searching contributions."
+
+      named_args number: 1
+    end
+  end
+
+  sig { void }
+  def contributions
+    args = contributions_args.parse
+
+    commits = 0
+    coauthorships = 0
+
+    all_repos = args.repositories.nil? || args.repositories.include?("all")
+    repos = all_repos ? SUPPORTED_REPOS : args.repositories
+
+    repos.each do |repo|
+      if SUPPORTED_REPOS.exclude?(repo)
+        return ofail "Unsupported repository: #{repo}. Try one of #{SUPPORTED_REPOS.join(", ")}."
+      end
+
+      repo_path = find_repo_path_for_repo(repo)
+      unless repo_path.exist?
+
+        opoo "Repository #{repo} not yet tapped! Tapping it now..."
+        Tap.fetch("homebrew", repo).install
+      end
+
+      commits += git_log_author_cmd(T.must(repo_path), args)
+      coauthorships += git_log_coauthor_cmd(T.must(repo_path), args)
+    end
+
+    sentence = "#{args.named.first} directly authored #{commits} commits " \
+               "and co-authored #{coauthorships} commits " \
+               "across #{all_repos ? "all Homebrew repos" : repos.to_sentence}"
+    sentence += if args.from && args.to
+      " between #{args.from} and #{args.to}"
+    elsif args.from
+      " after #{args.from}"
+    elsif args.to
+      " before #{args.to}"
+    else
+      " in all time"
+    end
+    sentence += "."
+
+    puts sentence
+  end
+
+  sig { params(repo: String).returns(Pathname) }
+  def find_repo_path_for_repo(repo)
+    return HOMEBREW_REPOSITORY if repo == "brew"
+
+    Tap.fetch("homebrew", repo).path
+  end
+
+  sig { params(repo_path: Pathname, args: Homebrew::CLI::Args).returns(Integer) }
+  def git_log_author_cmd(repo_path, args)
+    cmd = ["git", "-C", repo_path, "log", "--oneline", "--author=#{args.named.first}"]
+    cmd << "--before=#{args.to}" if args.to
+    cmd << "--after=#{args.from}" if args.from
+
+    Utils.safe_popen_read(*cmd).lines.count
+  end
+
+  sig { params(repo_path: Pathname, args: Homebrew::CLI::Args).returns(Integer) }
+  def git_log_coauthor_cmd(repo_path, args)
+    cmd = ["git", "-C", repo_path, "log", "--oneline"]
+    cmd << "--format='%(trailers:key=Co-authored-by:)'"
+    cmd << "--before=#{args.to}" if args.to
+    cmd << "--after=#{args.from}" if args.from
+
+    Utils.safe_popen_read(*cmd).lines.count { |l| l.include?(args.named.first) }
+  end
+end
diff --git a/Library/Homebrew/test/dev-cmd/contributions_spec.rb b/Library/Homebrew/test/dev-cmd/contributions_spec.rb
new file mode 100644
index 0000000000..bd60333dc0
--- /dev/null
+++ b/Library/Homebrew/test/dev-cmd/contributions_spec.rb
@@ -0,0 +1,8 @@
+# typed: false
+# frozen_string_literal: true
+
+require "cmd/shared_examples/args_parse"
+
+describe "brew contributions" do
+  it_behaves_like "parseable arguments"
+end