Reraise the error so the outer executor can grab the error

app/models/solid_queue/claimed_execution.rb

@@ -87,6 +87,7 @@ def failed_with(error)
       job.failed_with(error)
       destroy!
     end
+    raise error
   end
 
   private

lib/solid_queue/pool.rb

@@ -19,14 +19,16 @@ def post(execution)
       available_threads.decrement
 
       future = Concurrent::Future.new(args: [ execution ], executor: executor) do |thread_execution|
-        thread_execution.perform
-      ensure
-        available_threads.increment
-        mutex.synchronize { on_idle.try(:call) if idle? }
-      end
-
-      future.add_observer do |_, _, error|
-        handle_thread_error(error) if error
+        begin
+          wrap_in_app_executor do
+            thread_execution.perform
+          end
+        rescue Exception
+          nil
+        ensure
+          available_threads.increment
+          mutex.synchronize { on_idle.try(:call) if idle? }
+        end
       end
 
       future.execute

test/unit/worker_test.rb

@@ -51,6 +51,28 @@ class WorkerTest < ActiveSupport::TestCase
     subscriber = ErrorBuffer.new
     Rails.error.subscribe(subscriber)
 
+    SolidQueue::ClaimedExecution::Result.expects(:new).raises(RuntimeError.new("everything is broken")).at_least_once
+
+    AddToBufferJob.perform_later "hey!"
+
+    @worker.start
+
+    wait_for_jobs_to_finish_for(1.second)
+    @worker.wake_up
+
+    assert_equal 1, subscriber.errors.count
+    assert_equal "everything is broken", subscriber.messages.first
+  ensure
+    Rails.error.unsubscribe(subscriber) if Rails.error.respond_to?(:unsubscribe)
+    SolidQueue.on_thread_error = original_on_thread_error
+  end
+
+  test "errors on claimed executions are reported via Rails error subscriber" do
+    original_on_thread_error, SolidQueue.on_thread_error = SolidQueue.on_thread_error, nil
+
+    subscriber = ErrorBuffer.new
+    Rails.error.subscribe(subscriber)
+
     RaisingJob.perform_later(RuntimeError, "B")
 
     @worker.start