diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 367e798afc..82a088d398 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -8,10 +8,12 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        ruby: ["3.0", "3.1", "3.2"]
+        ruby: ["3.0", "3.1", "3.2", "truffleruby", "truffleruby-head"]
         exclude:
           - os: windows-latest
-            ruby: "3.3"
+            ruby: "truffleruby-head"
+          - os: windows-latest
+            ruby: "truffleruby"
     runs-on: ${{ matrix.os }}
     name: Ruby ${{ matrix.ruby }} on ${{ matrix.os }}
     steps:
diff --git a/test/integration_test.rb b/test/integration_test.rb
index 146ad637f9..86a4189649 100644
--- a/test/integration_test.rb
+++ b/test/integration_test.rb
@@ -41,10 +41,22 @@ def teardown
     make_request("shutdown")
     send_request("exit")
 
-    # Make sure IOs are closed
-    @stdin.close
-    @stdout.close
-    @stderr.close
+    # Give the server some time to process the "shutdown" and "exit" messages before
+    # closing the streams. Otherwise, it's possible the server misses one or both of them
+    # depending on what it's currently processing. This is wrapped in a timeout in case
+    # the server fails to process the messages.
+    begin
+      Timeout.timeout(60) do
+        sleep(0.010) while @wait_thr.alive?
+      end
+    rescue Timeout::Error
+      raise "The LSP server failed to shut down cleanly."
+    ensure
+      # Make sure IOs are closed
+      @stdin.close
+      @stdout.close
+      @stderr.close
+    end
 
     # Make sure the exit status is zero
     assert_equal(0, @wait_thr.value)
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 94fda1e01a..99b1491913 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -10,11 +10,13 @@
 require "minitest/autorun"
 require "minitest/reporters"
 require "tempfile"
-require "debug"
 require "mocha/minitest"
 
-sorbet_paths = Gem.loaded_specs["sorbet-runtime"].full_require_paths.freeze
-DEBUGGER__::CONFIG[:skip_path] = Array(DEBUGGER__::CONFIG[:skip_path]) + sorbet_paths
+unless RUBY_ENGINE == "truffleruby" || RUBY_PLATFORM =~ /mingw|mswin/
+  require "debug"
+  sorbet_paths = Gem.loaded_specs["sorbet-runtime"].full_require_paths.freeze
+  DEBUGGER__::CONFIG[:skip_path] = Array(DEBUGGER__::CONFIG[:skip_path]) + sorbet_paths
+end
 
 minitest_reporter = if ENV["SPEC_REPORTER"]
   Minitest::Reporters::SpecReporter.new(color: true)