diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index e677a6b1..e3066e67 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -11,8 +11,6 @@ jobs:
         ruby-version:
           - "3.0"
           - "2.7"
-          - "2.6"
-          - "2.5"
 
     steps:
     - uses: actions/checkout@v2
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 69192d1f..97be47bd 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -11,8 +11,6 @@ jobs:
         ruby-version:
           - "3.0"
           - "2.7"
-          - "2.6"
-          - "2.5"
 
     steps:
     - uses: actions/checkout@v2
diff --git a/autobuild.gemspec b/autobuild.gemspec
index ef1cdf9b..d36f37bf 100644
--- a/autobuild.gemspec
+++ b/autobuild.gemspec
@@ -34,7 +34,7 @@ Gem::Specification.new do |s|
     s.add_runtime_dependency 'tty-screen', '~> 0.8.0'
     s.add_runtime_dependency "utilrb", "~> 3.0", ">= 3.0"
     s.add_development_dependency "fakefs"
-    s.add_development_dependency "flexmock", '~> 2.0', ">= 2.0.0"
+    s.add_development_dependency "flexmock"
     s.add_development_dependency "minitest", "~> 5.0", ">= 5.0"
     s.add_development_dependency "simplecov"
     s.add_development_dependency "timecop"
diff --git a/test/import/test_git.rb b/test/import/test_git.rb
index 1f64e432..f8917c26 100644
--- a/test/import/test_git.rb
+++ b/test/import/test_git.rb
@@ -275,7 +275,7 @@
                         any, :import, 'git', 'clone', '-o', 'autobuild',
                         File.join(tempdir, 'gitrepo.git'),
                         File.join(tempdir, 'git'), any
-                    )
+                    ).with_any_kw_args
 
                 flexmock(Autobuild::Subprocess).should_receive(:run).pass_thru
 
@@ -297,7 +297,7 @@ def assert_clone(*args)
                     any, :import, 'git', 'clone', '-o', 'autobuild', *args,
                     File.join(tempdir, 'gitrepo.git'),
                     File.join(tempdir, 'git'), any
-                ).once.pass_thru
+                ).with_any_kw_args.once.pass_thru
 
             flexmock(Autobuild::Subprocess).should_receive(:run).pass_thru
         end
@@ -992,6 +992,7 @@ def pin_importer(id, options = Hash.new)
                 .should_receive(:run)
                 .with(any, :import, 'git', '--git-dir', File.join(pkg.srcdir, ".git"),
                       'symbolic-ref', "refs/remotes/autobuild/HEAD", any)
+                .with_any_kw_args
                 .once
                 .and_return(['refs/remotes/autobuild/temp/branch', 'bla'])
             flexmock(Autobuild::Subprocess).should_receive(:run).pass_thru
@@ -1027,6 +1028,7 @@ def pin_importer(id, options = Hash.new)
                     any, :import, 'git', 'ls-remote', '--symref',
                     File.join(tempdir, 'gitrepo-nomaster.git'), any
                 )
+                .with_any_kw_args
                 .once
                 .and_return(['ref: refs/heads/temp/branch HEAD', 'bla'])
             flexmock(Autobuild::Subprocess).should_receive(:run).pass_thru