diff --git a/.github/workflows/plugin-linting.yml b/.github/workflows/plugin-linting.yml
index c807794..6d2bb97 100644
--- a/.github/workflows/plugin-linting.yml
+++ b/.github/workflows/plugin-linting.yml
@@ -55,3 +55,12 @@ jobs:
       - name: Rubocop
         if: ${{ !cancelled() }}
         run: bundle exec rubocop .
+
+      - name: Syntax Tree
+        if: ${{ !cancelled() }}
+        run: |
+          if test -f .streerc; then
+            bundle exec stree check Gemfile $(git ls-files '*.rb') $(git ls-files '*.rake')
+          else
+            echo "Stree config not detected for this repository. Skipping."
+          fi
diff --git a/.github/workflows/plugin-tests.yml b/.github/workflows/plugin-tests.yml
index 9d390bc..f30a5be 100644
--- a/.github/workflows/plugin-tests.yml
+++ b/.github/workflows/plugin-tests.yml
@@ -80,7 +80,7 @@ jobs:
 
       - name: Get yarn cache directory
         id: yarn-cache-dir
-        run: echo "::set-output name=dir::$(yarn cache dir)"
+        run: echo "dir=$(yarn cache dir)" >> $GITHUB_OUTPUT
 
       - name: Yarn cache
         uses: actions/cache@v3
@@ -130,7 +130,7 @@ jobs:
         shell: bash
         run: |
           if [ 0 -lt $(find plugins/${{ github.event.repository.name }}/spec -type f -name "*.rb" 2> /dev/null | wc -l) ]; then
-            echo "::set-output name=files_exist::true"
+            echo "files_exist=true" >> $GITHUB_OUTPUT
           fi
 
       - name: Plugin RSpec
@@ -142,7 +142,7 @@ jobs:
         shell: bash
         run: |
           if [ 0 -lt $(find plugins/${{ github.event.repository.name }}/test/javascripts -type f \( -name "*.js" -or -name "*.es6" \) 2> /dev/null | wc -l) ]; then
-            echo "::set-output name=files_exist::true"
+            echo "files_exist=true" >> $GITHUB_OUTPUT
           fi
 
       - name: Plugin QUnit
diff --git a/.rubocop.yml b/.rubocop.yml
index d46296c..fb14dfa 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,2 +1,2 @@
 inherit_gem:
-  rubocop-discourse: default.yml
+  rubocop-discourse: stree-compat.yml
diff --git a/.streerc b/.streerc
new file mode 100644
index 0000000..0bc4379
--- /dev/null
+++ b/.streerc
@@ -0,0 +1,2 @@
+--print-width=100
+--plugins=plugin/trailing_comma
diff --git a/Gemfile.lock b/Gemfile.lock
index 9ccd6c3..8c5185d 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -6,7 +6,7 @@ GEM
     parallel (1.22.1)
     parser (3.1.3.0)
       ast (~> 2.4.1)
-    prettier_print (0.1.0)
+    prettier_print (1.1.0)
     rainbow (3.1.1)
     regexp_parser (2.6.1)
     rexml (3.2.5)
@@ -28,8 +28,8 @@ GEM
     rubocop-rspec (2.16.0)
       rubocop (~> 1.33)
     ruby-progressbar (1.11.0)
-    syntax_tree (3.2.1)
-      prettier_print
+    syntax_tree (5.0.1)
+      prettier_print (>= 1.1.0)
     unicode-display_width (2.3.0)
 
 PLATFORMS
diff --git a/lib/discourse_calendar.rb b/lib/discourse_calendar.rb
index 3e7f36f..837ce11 100644
--- a/lib/discourse_calendar.rb
+++ b/lib/discourse_calendar.rb
@@ -2,6 +2,6 @@
 
 module DiscourseAssign
   module DiscourseCalendar
-    HOLIDAY_CUSTOM_FIELD ||= 'on_holiday'
+    HOLIDAY_CUSTOM_FIELD ||= "on_holiday"
   end
 end
diff --git a/lib/random_assign_utils.rb b/lib/random_assign_utils.rb
index 4531239..fc0edaa 100644
--- a/lib/random_assign_utils.rb
+++ b/lib/random_assign_utils.rb
@@ -23,9 +23,9 @@ class RandomAssignUtils
     min_hours = fields.dig("minimum_time_between_assignments", "value").presence
     if min_hours &&
          TopicCustomField
-             .where(name: "assigned_to_id", topic_id: topic_id)
-             .where("created_at < ?", min_hours.to_i.hours.ago)
-             .exists?
+           .where(name: "assigned_to_id", topic_id: topic_id)
+           .where("created_at < ?", min_hours.to_i.hours.ago)
+           .exists?
       log_info(automation, "Topic(#{topic_id}) has already been assigned recently")
       return
     end
diff --git a/spec/lib/assigner_spec.rb b/spec/lib/assigner_spec.rb
index 6360e3e..4f9b9bb 100644
--- a/spec/lib/assigner_spec.rb
+++ b/spec/lib/assigner_spec.rb
@@ -46,14 +46,13 @@ RSpec.describe Assigner do
     it "deletes notification for original assignee when reassigning" do
       Jobs.run_immediately!
 
-      expect {
-        described_class.new(topic, admin).assign(moderator)
-      }.to change { moderator.notifications.count }.by(1)
+      expect { described_class.new(topic, admin).assign(moderator) }.to change {
+        moderator.notifications.count
+      }.by(1)
 
-      expect {
-        described_class.new(topic, admin).assign(moderator_2)
-      }.to change { moderator.notifications.count }.by(-1)
-        .and change { moderator_2.notifications.count }.by(1)
+      expect { described_class.new(topic, admin).assign(moderator_2) }.to change {
+        moderator.notifications.count
+      }.by(-1).and change { moderator_2.notifications.count }.by(1)
     end
 
     it "can assign with note" do
diff --git a/spec/requests/assign_controller_spec.rb b/spec/requests/assign_controller_spec.rb
index 90b9422..c9611b7 100644
--- a/spec/requests/assign_controller_spec.rb
+++ b/spec/requests/assign_controller_spec.rb
@@ -10,7 +10,12 @@ RSpec.describe DiscourseAssign::AssignController do
   let(:user) { Fabricate(:admin, name: "Robin Ward", username: "eviltrout") }
   fab!(:post) { Fabricate(:post) }
   fab!(:user2) do
-    Fabricate(:active_user, name: "David Taylor", username: "david", groups: [default_allowed_group])
+    Fabricate(
+      :active_user,
+      name: "David Taylor",
+      username: "david",
+      groups: [default_allowed_group],
+    )
   end
   let(:non_admin) { Fabricate(:user, groups: [default_allowed_group]) }
   fab!(:normal_user) { Fabricate(:user) }
@@ -91,9 +96,7 @@ RSpec.describe DiscourseAssign::AssignController do
   end
 
   describe "#suggestions" do
-    before do
-      sign_in(user)
-    end
+    before { sign_in(user) }
 
     it "suggests the current user + the last 6 previously assigned users" do
       assignees = 10.times.map { |_| assign_user_to_post.username }
@@ -106,7 +109,9 @@ RSpec.describe DiscourseAssign::AssignController do
 
     it "doesn't suggest users on holiday" do
       user_on_vacation = assign_user_to_post
-      user_on_vacation.upsert_custom_fields(DiscourseAssign::DiscourseCalendar::HOLIDAY_CUSTOM_FIELD => "t")
+      user_on_vacation.upsert_custom_fields(
+        DiscourseAssign::DiscourseCalendar::HOLIDAY_CUSTOM_FIELD => "t",
+      )
 
       get "/assign/suggestions.json"