diff --git a/lib/solid_queue/configuration.rb b/lib/solid_queue/configuration.rb
index b547d12c..d04a0aaa 100644
--- a/lib/solid_queue/configuration.rb
+++ b/lib/solid_queue/configuration.rb
@@ -3,9 +3,12 @@
 module SolidQueue
   class Configuration
     include ActiveModel::Model
+    include ActiveModel::Validations::Callbacks
 
-    validate :ensure_configured_processes
-    validate :ensure_valid_recurring_tasks
+    validate :ensure_configured_processes, :ensure_valid_recurring_tasks
+    validate :warn_about_incorrectly_sized_thread_pool, :warn_about_missing_config_files
+
+    before_validation { warnings.clear }
 
     class Process < Struct.new(:kind, :attributes)
       def instantiate
@@ -46,43 +49,30 @@ def configured_processes
       end
     end
 
-    def error_messages
-      if configured_processes.none?
-        "No workers or processed configured. Exiting..."
-      else
-        error_messages = invalid_tasks.map do |task|
-            all_messages = task.errors.full_messages.map { |msg| "\t#{msg}" }.join("\n")
-            "#{task.key}:\n#{all_messages}"
-          end
-          .join("\n")
-
-        "Invalid processes configured:\n#{error_messages}"
-      end
-    end
-
     def mode
-      @options[:mode].to_s.inquiry
+      options[:mode].to_s.inquiry
     end
 
     def standalone?
-      mode.fork? || @options[:standalone]
+      mode.fork? || options[:standalone]
     end
 
     def warnings
-      @warnings ||= [ undersized_thread_pool_message ].compact
+      @warnings ||= ActiveModel::Errors.new(self)
     end
 
     def check
-      warnings.each { |warning| $stdout.puts "Warning: #{warning}" }
-
       if valid?
+        warnings.full_messages.each { |warning| $stderr.puts warning }
         $stdout.puts "Solid Queue configuration is valid."
+
         true
       else
-        $stderr.puts "Invalid Solid Queue configuration:"
-        errors.full_messages.each do |message|
+        $stderr.puts "Solid Queue configuration is invalid:"
+        (warnings.full_messages + errors.full_messages).each do |message|
           message.each_line { |line| $stderr.puts "  #{line.chomp}" }
         end
+
         false
       end
     end
@@ -90,18 +80,6 @@ def check
     private
       attr_reader :options
 
-      def undersized_thread_pool_message
-        db_pool_size = SolidQueue::Record.connection_pool&.size
-
-        if db_pool_size && db_pool_size < estimated_number_of_threads
-          "Solid Queue is configured to use #{estimated_number_of_threads} threads but the " \
-            "database connection pool is #{db_pool_size}. Increase it in `config/database.yml`"
-        end
-      rescue ActiveRecord::ActiveRecordError
-        # No usable database connection. Skip the pool-size warning in that case.
-        nil
-      end
-
       def ensure_configured_processes
         unless configured_processes.any?
           errors.add(:base, "No processes configured")
@@ -118,6 +96,28 @@ def ensure_valid_recurring_tasks
         end
       end
 
+      def warn_about_incorrectly_sized_thread_pool
+        db_pool_size = SolidQueue::Record.connection_pool&.size
+
+        if db_pool_size && db_pool_size < estimated_number_of_threads
+          warnings.add(:base, "Warning: Solid Queue is configured to use #{estimated_number_of_threads} threads but the " \
+            "database connection pool is #{db_pool_size}. Increase it in `config/database.yml`")
+        end
+      rescue ActiveRecord::ActiveRecordError
+        # No usable database connection. Skip the pool-size warning in that case.
+      end
+
+      def warn_about_missing_config_files
+        files = [ options[:config_file] ]
+        files << options[:recurring_schedule_file] unless skip_recurring_tasks?
+
+        files.compact.each do |file|
+          unless Pathname.new(file).exist?
+            warnings.add(:base, "Warning: provided configuration file '#{file}' does not exist. Falling back to default configuration.")
+          end
+        end
+      end
+
       def default_options
         {
           mode: ENV["SOLID_QUEUE_SUPERVISOR_MODE"] || :fork,
@@ -244,7 +244,6 @@ def load_config_from_file(file)
         if file.exist?
           ActiveSupport::ConfigurationFile.parse(file).deep_symbolize_keys
         else
-          puts "[solid_queue] WARNING: Provided configuration file '#{file}' does not exist. Falling back to default configuration."
           {}
         end
       end
diff --git a/lib/solid_queue/supervisor.rb b/lib/solid_queue/supervisor.rb
index ffd4d3bd..17b90c54 100644
--- a/lib/solid_queue/supervisor.rb
+++ b/lib/solid_queue/supervisor.rb
@@ -13,7 +13,7 @@ def start(**options)
         configuration = Configuration.new(**options)
 
         if configuration.valid?
-          configuration.warnings.each { |warning| SolidQueue.logger.warn(warning) }
+          configuration.warnings.full_messages.each { |warning| SolidQueue.logger.warn(warning) }
 
           klass = configuration.mode.fork? ? ForkSupervisor : AsyncSupervisor
           klass.new(configuration).tap(&:start)
diff --git a/lib/solid_queue/tasks.rb b/lib/solid_queue/tasks.rb
index 026cb42e..70422562 100644
--- a/lib/solid_queue/tasks.rb
+++ b/lib/solid_queue/tasks.rb
@@ -11,6 +11,7 @@
 
   desc "validate the Solid Queue configuration for the current Rails env without starting any process"
   task check: :environment do
-    exit 1 unless SolidQueue::Configuration.new.check
+    configuration = SolidQueue::Configuration.new
+    exit 1 unless configuration.check
   end
 end
diff --git a/test/unit/cli_test.rb b/test/unit/cli_test.rb
index 12e97dcf..f3d5415a 100644
--- a/test/unit/cli_test.rb
+++ b/test/unit/cli_test.rb
@@ -51,7 +51,7 @@ class CliTest < ActiveSupport::TestCase
     )
 
     assert_equal 1, exit_status
-    assert_match "Invalid Solid Queue configuration", err
+    assert_match "Solid Queue configuration is invalid", err
     assert_match "periodic_invalid_class", err
     assert_match "periodic_incorrect_schedule", err
     assert_empty out
diff --git a/test/unit/configuration_test.rb b/test/unit/configuration_test.rb
index aeec5e5b..7bb7f70a 100644
--- a/test/unit/configuration_test.rb
+++ b/test/unit/configuration_test.rb
@@ -27,10 +27,11 @@ class ConfigurationTest < ActiveSupport::TestCase
   end
 
   test "warns if provided configuration file does not exist" do
-    assert_output "[solid_queue] WARNING: Provided configuration file '/path/to/nowhere.yml' does not exist. Falling back to default configuration.\n" do
-      configuration = SolidQueue::Configuration.new(config_file: Pathname.new("/path/to/nowhere.yml"))
-      assert configuration.valid?
-    end
+    configuration = SolidQueue::Configuration.new(config_file: Pathname.new("/path/to/nowhere.yml"))
+
+    assert configuration.valid?
+    assert_includes configuration.warnings.full_messages,
+      "Warning: provided configuration file '/path/to/nowhere.yml' does not exist. Falling back to default configuration."
   end
 
   test "read configuration from default file" do
@@ -145,20 +146,20 @@ class ConfigurationTest < ActiveSupport::TestCase
     assert error.include?("periodic_invalid_class: Class name doesn't correspond to an existing class")
     assert error.include?("periodic_incorrect_schedule: Schedule is not a supported recurring schedule")
 
-    assert_output(/Provided configuration file '[^']+' does not exist\./) do
-      assert SolidQueue::Configuration.new(recurring_schedule_file: config_file_path(:empty_recurring)).valid?
-    end
+    configuration = SolidQueue::Configuration.new(recurring_schedule_file: config_file_path(:empty_recurring))
+    assert configuration.valid?
+    assert_match(/provided configuration file '[^']+' does not exist\./, configuration.warnings.full_messages.join)
+
     assert SolidQueue::Configuration.new(skip_recurring: true).valid?
 
     configuration = SolidQueue::Configuration.new(recurring_schedule_file: config_file_path(:recurring_with_production_only))
     assert configuration.valid?
     assert_processes configuration, :scheduler, 0
 
-    assert_output(/Provided configuration file '[^']+' does not exist\./) do
-      configuration = SolidQueue::Configuration.new(recurring_schedule_file: config_file_path(:recurring_with_empty))
-      assert configuration.valid?
-      assert_processes configuration, :scheduler, 0
-    end
+    configuration = SolidQueue::Configuration.new(recurring_schedule_file: config_file_path(:recurring_with_empty))
+    assert configuration.valid?
+    assert_processes configuration, :scheduler, 0
+    assert_match(/provided configuration file '[^']+' does not exist\./, configuration.warnings.full_messages.join)
 
     # No processes
     configuration = SolidQueue::Configuration.new(skip_recurring: true, dispatchers: [], workers: [])
@@ -175,15 +176,24 @@ class ConfigurationTest < ActiveSupport::TestCase
 
     assert configuration.valid?
     assert_equal 1, configuration.warnings.size
-    assert_match /Solid Queue is configured to use \d+ threads but the database connection pool is \d+\. Increase it in `config\/database.yml`/, configuration.warnings.first
+    assert_match /Solid Queue is configured to use \d+ threads but the database connection pool is \d+\. Increase it in `config\/database.yml`/, configuration.warnings.full_messages.first
   end
 
   test "has no warnings when the database connection pool is large enough" do
     configuration = SolidQueue::Configuration.new(workers: [ { queues: "background", threads: 1, polling_interval: 10 } ], skip_recurring: true)
 
+    assert configuration.valid?
     assert_empty configuration.warnings
   end
 
+  test "does not duplicate warnings when validated more than once" do
+    configuration = SolidQueue::Configuration.new(workers: [ { queues: "background", threads: 50, polling_interval: 10 } ], skip_recurring: true)
+
+    3.times { configuration.valid? }
+
+    assert_equal 1, configuration.warnings.size
+  end
+
   test "check prints a success message and returns true for a valid configuration" do
     out, err = capture_io do
       assert SolidQueue::Configuration.new(skip_recurring: true).check
@@ -193,13 +203,13 @@ class ConfigurationTest < ActiveSupport::TestCase
     assert_empty err
   end
 
-  test "check prints warnings to stdout on the valid path" do
-    out, _err = capture_io do
+  test "check prints warnings to stderr on the valid path" do
+    out, err = capture_io do
       assert SolidQueue::Configuration.new(workers: [ { queues: "background", threads: 50, polling_interval: 10 } ], skip_recurring: true).check
     end
 
     assert_match "Solid Queue configuration is valid.", out
-    assert_match /Warning: Solid Queue is configured to use \d+ threads but the database connection pool is \d+/, out
+    assert_match /Solid Queue is configured to use \d+ threads but the database connection pool is \d+/, err
   end
 
   test "check prints errors to stderr and returns false for an invalid configuration" do
@@ -207,7 +217,7 @@ class ConfigurationTest < ActiveSupport::TestCase
       assert_not SolidQueue::Configuration.new(recurring_schedule_file: config_file_path(:recurring_with_invalid)).check
     end
 
-    assert_match "Invalid Solid Queue configuration:", err
+    assert_match "Solid Queue configuration is invalid:", err
     assert_match "periodic_invalid_class", err
   end
 
diff --git a/test/unit/rake_tasks_test.rb b/test/unit/rake_tasks_test.rb
index 8b2de143..717bd980 100644
--- a/test/unit/rake_tasks_test.rb
+++ b/test/unit/rake_tasks_test.rb
@@ -44,7 +44,7 @@ class RakeTasksTest < ActiveSupport::TestCase
 
     assert_equal 1, status
     assert_empty out
-    assert_match "Invalid Solid Queue configuration:", err
+    assert_match "Solid Queue configuration is invalid:", err
     assert_match "broken", err
   end
 end