diff --git a/judoscale-ruby/lib/judoscale/config.rb b/judoscale-ruby/lib/judoscale/config.rb
index 0da928f5..c3951c4b 100644
--- a/judoscale-ruby/lib/judoscale/config.rb
+++ b/judoscale-ruby/lib/judoscale/config.rb
@@ -89,9 +89,11 @@ def reset
         @api_base_url ||= "https://adapter.judoscale.com/api/#{ENV["RENDER_SERVICE_ID"]}"
       elsif ENV["DYNO"]
         @current_runtime_container = RuntimeContainer.new ENV["DYNO"]
+      elsif (metadata_uri = ENV["ECS_CONTAINER_METADATA_URI"])
+        @current_runtime_container = RuntimeContainer.new(metadata_uri.split("/").last)
       else
         # unsupported platform? Don't want to leave @current_runtime_container nil though
-        @current_runtime_container = RuntimeContainer.new
+        @current_runtime_container = RuntimeContainer.new("")
       end
     end
 
diff --git a/judoscale-ruby/test/config_test.rb b/judoscale-ruby/test/config_test.rb
index 45c0e4a9..ad4c34ba 100644
--- a/judoscale-ruby/test/config_test.rb
+++ b/judoscale-ruby/test/config_test.rb
@@ -60,6 +60,20 @@ module Judoscale
       end
     end
 
+    it "initializes the config from default Amazon ECS ENV vars" do
+      # Users must set JUDOSCALE_URL manually when using Amazon ECS.
+      env = {
+        "ECS_CONTAINER_METADATA_URI" => "http://169.254.170.2/v3/a8880ee042bc4db3ba878dce65b769b6-2750272591",
+        "JUDOSCALE_URL" => "https://adapter.judoscale.com/api/1234567890"
+      }
+
+      use_env env do
+        config = Config.instance
+        _(config.api_base_url).must_equal "https://adapter.judoscale.com/api/1234567890"
+        _(config.current_runtime_container).must_equal "a8880ee042bc4db3ba878dce65b769b6-2750272591"
+      end
+    end
+
     it "allows ENV vars config overrides for the debug and URL" do
       env = {
         "DYNO" => "web.2",