diff --git a/gemfiles/5.2.gemfile b/gemfiles/5.2.gemfile
deleted file mode 100644
index 7d57591..0000000
--- a/gemfiles/5.2.gemfile
+++ /dev/null
@@ -1,7 +0,0 @@
-# This file was generated by Appraisal
-
-source "https://rubygems.org"
-
-gem "activerecord", "~> 5.2"
-
-gemspec path: "../"
diff --git a/gemfiles/5.2.gemfile.lock b/gemfiles/5.2.gemfile.lock
deleted file mode 100644
index 1e43107..0000000
--- a/gemfiles/5.2.gemfile.lock
+++ /dev/null
@@ -1,79 +0,0 @@
-PATH
-  remote: ..
-  specs:
-    active_record_distinct_on (1.4.0)
-      activerecord (>= 5.2, < 7.1)
-
-GEM
-  remote: https://rubygems.org/
-  specs:
-    activemodel (5.2.6)
-      activesupport (= 5.2.6)
-    activerecord (5.2.6)
-      activemodel (= 5.2.6)
-      activesupport (= 5.2.6)
-      arel (>= 9.0)
-    activesupport (5.2.6)
-      concurrent-ruby (~> 1.0, >= 1.0.2)
-      i18n (>= 0.7, < 2)
-      minitest (~> 5.1)
-      tzinfo (~> 1.1)
-    appraisal (2.4.1)
-      bundler
-      rake
-      thor (>= 0.14.0)
-    arel (9.0.0)
-    coderay (1.1.3)
-    concurrent-ruby (1.1.9)
-    diff-lcs (1.4.4)
-    docile (1.4.0)
-    i18n (1.8.11)
-      concurrent-ruby (~> 1.0)
-    method_source (1.0.0)
-    minitest (5.14.4)
-    pry (0.14.1)
-      coderay (~> 1.1)
-      method_source (~> 1.0)
-    rake (13.0.6)
-    rspec (3.10.0)
-      rspec-core (~> 3.10.0)
-      rspec-expectations (~> 3.10.0)
-      rspec-mocks (~> 3.10.0)
-    rspec-core (3.10.1)
-      rspec-support (~> 3.10.0)
-    rspec-expectations (3.10.1)
-      diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.10.0)
-    rspec-mocks (3.10.2)
-      diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.10.0)
-    rspec-support (3.10.3)
-    simplecov (0.21.2)
-      docile (~> 1.1)
-      simplecov-html (~> 0.11)
-      simplecov_json_formatter (~> 0.1)
-    simplecov-html (0.12.3)
-    simplecov_json_formatter (0.1.3)
-    sqlite3 (1.4.2)
-    thor (1.1.0)
-    thread_safe (0.3.6)
-    tzinfo (1.2.9)
-      thread_safe (~> 0.1)
-
-PLATFORMS
-  ruby
-  x86_64-linux
-
-DEPENDENCIES
-  active_record_distinct_on!
-  activerecord (~> 5.2)
-  appraisal
-  bundler
-  pry
-  rake (>= 12.3.3)
-  rspec
-  simplecov
-  sqlite3
-
-BUNDLED WITH
-   2.2.31
diff --git a/gemfiles/6.0.gemfile b/gemfiles/6.0.gemfile
deleted file mode 100644
index 5b48be1..0000000
--- a/gemfiles/6.0.gemfile
+++ /dev/null
@@ -1,7 +0,0 @@
-# This file was generated by Appraisal
-
-source "https://rubygems.org"
-
-gem "activerecord", "~> 6.0"
-
-gemspec path: "../"
diff --git a/gemfiles/6.0.gemfile.lock b/gemfiles/6.0.gemfile.lock
deleted file mode 100644
index 7defade..0000000
--- a/gemfiles/6.0.gemfile.lock
+++ /dev/null
@@ -1,78 +0,0 @@
-PATH
-  remote: ..
-  specs:
-    active_record_distinct_on (1.4.0)
-      activerecord (>= 5.2, < 7.1)
-
-GEM
-  remote: https://rubygems.org/
-  specs:
-    activemodel (6.1.4.1)
-      activesupport (= 6.1.4.1)
-    activerecord (6.1.4.1)
-      activemodel (= 6.1.4.1)
-      activesupport (= 6.1.4.1)
-    activesupport (6.1.4.1)
-      concurrent-ruby (~> 1.0, >= 1.0.2)
-      i18n (>= 1.6, < 2)
-      minitest (>= 5.1)
-      tzinfo (~> 2.0)
-      zeitwerk (~> 2.3)
-    appraisal (2.4.1)
-      bundler
-      rake
-      thor (>= 0.14.0)
-    coderay (1.1.3)
-    concurrent-ruby (1.1.9)
-    diff-lcs (1.4.4)
-    docile (1.4.0)
-    i18n (1.8.11)
-      concurrent-ruby (~> 1.0)
-    method_source (1.0.0)
-    minitest (5.14.4)
-    pry (0.14.1)
-      coderay (~> 1.1)
-      method_source (~> 1.0)
-    rake (13.0.6)
-    rspec (3.10.0)
-      rspec-core (~> 3.10.0)
-      rspec-expectations (~> 3.10.0)
-      rspec-mocks (~> 3.10.0)
-    rspec-core (3.10.1)
-      rspec-support (~> 3.10.0)
-    rspec-expectations (3.10.1)
-      diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.10.0)
-    rspec-mocks (3.10.2)
-      diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.10.0)
-    rspec-support (3.10.3)
-    simplecov (0.21.2)
-      docile (~> 1.1)
-      simplecov-html (~> 0.11)
-      simplecov_json_formatter (~> 0.1)
-    simplecov-html (0.12.3)
-    simplecov_json_formatter (0.1.3)
-    sqlite3 (1.4.2)
-    thor (1.1.0)
-    tzinfo (2.0.4)
-      concurrent-ruby (~> 1.0)
-    zeitwerk (2.5.1)
-
-PLATFORMS
-  ruby
-  x86_64-linux
-
-DEPENDENCIES
-  active_record_distinct_on!
-  activerecord (~> 6.0)
-  appraisal
-  bundler
-  pry
-  rake (>= 12.3.3)
-  rspec
-  simplecov
-  sqlite3
-
-BUNDLED WITH
-   2.2.31