diff --git a/Gemfile b/Gemfile
index adaf808..84c4af5 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,12 +2,15 @@
 
 source 'https://rubygems.org'
 
-LOCAL_GEM_PATH = ENV.fetch('LOCAL_GEMS', '..')
+AVAILABLE_LOCAL_GEMS = %w[ffi].freeze
+LOCAL_GEM_PATH = ENV.fetch('LOCAL_GEM_PATH', '..')
+LOCAL_GEMS = ENV.fetch('LOCAL_GEMS', AVAILABLE_LOCAL_GEMS.join(';')).split(/[,;]|\s+/)
+
 def local_gem(gem_name, **options)
   options[:path] = "#{LOCAL_GEM_PATH}/#{gem_name}" if Dir.exist?("#{LOCAL_GEM_PATH}/#{gem_name}")
   gem gem_name, **options
 end
 
-%w[ffi].each { |g| local_gem g }
+(AVAILABLE_LOCAL_GEMS & LOCAL_GEMS).each { |g| local_gem(g) }
 
 gemspec
diff --git a/lib/ffi/libfuse/gem_helper.rb b/lib/ffi/libfuse/gem_helper.rb
index f731850..bdc916e 100644
--- a/lib/ffi/libfuse/gem_helper.rb
+++ b/lib/ffi/libfuse/gem_helper.rb
@@ -5,13 +5,6 @@ module FFI
   module Libfuse
     # @!visibility private
     class GemHelper
-      SEMVER_TAG_REGEX = /^v\d+\.\d+\.\d+/.freeze
-
-      # branches the format is refs/heads/<branch_name>,
-      # tags it is refs/tags/<tag_name>.
-      # for pull requests it is refs/pull/<pr_number>/merge,
-      GIT_REF_TYPES = { 'heads' => :branch, 'tags' => :tag, 'pull' => :pull }.freeze
-
       class << self
         # set when install'd.
         attr_accessor :instance
@@ -33,7 +26,7 @@ def git_ref(env: ENV)
           return [ref, nil] unless ref&.start_with?('refs/')
 
           _refs, ref_type, ref_name = ref.split('/', 3)
-          [ref_name, GIT_REF_TYPES[ref_type]]
+          [ref_name, { 'heads' => :branch, 'tags' => :tag, 'pull' => :pull }[ref_type]]
         end
 
         def gem_version(main_branch:, version:, env: ENV)
@@ -44,7 +37,7 @@ def gem_version(main_branch:, version:, env: ENV)
             when :branch
               ref_name == main_branch ? [version] : [version, ref_name]
             when :tag
-              SEMVER_TAG_REGEX.match?(ref_name) ? [ref_name[1..]] : [version, ref_name]
+              /^v\d+\.\d+\.\d+/.match?(ref_name) ? [ref_name[1..]] : [version, ref_name]
             when :pull
               pr_number, merge, _rest = ref_name.split('/')
               # GITHUB_BASE_REF	The name of the base ref or target branch of the pull request in a workflow run