diff --git a/spec/acceptance/throttling_spec.rb b/spec/acceptance/throttling_spec.rb
index 2ad4605..396589a 100644
--- a/spec/acceptance/throttling_spec.rb
+++ b/spec/acceptance/throttling_spec.rb
@@ -2,9 +2,11 @@ require_relative "../spec_helper"
 require "timecop"
 
 describe "#throttle" do
-  it "allows one request per minute by IP" do
+  before do
     Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
+  end
 
+  it "allows one request per minute by IP" do
     Rack::Attack.throttle("by ip", limit: 1, period: 60) do |request|
       request.ip
     end
@@ -29,4 +31,85 @@ describe "#throttle" do
       assert_equal 200, last_response.status
     end
   end
+
+  it "supports limit to be dynamic" do
+    # Could be used to have different rate limits for authorized
+    # vs general requests
+    limit_proc = lambda do |request|
+      if request.env["X-APIKey"] == "private-secret"
+        2
+      else
+        1
+      end
+    end
+
+    Rack::Attack.throttle("by ip", limit: limit_proc, period: 60) do |request|
+      request.ip
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+    assert_equal 200, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+    assert_equal 429, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+    assert_equal 200, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+    assert_equal 200, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+    assert_equal 429, last_response.status
+  end
+
+  it "supports period to be dynamic" do
+    # Could be used to have different rate limits for authorized
+    # vs general requests
+    period_proc = lambda do |request|
+      if request.env["X-APIKey"] == "private-secret"
+        10
+      else
+        30
+      end
+    end
+
+    Rack::Attack.throttle("by ip", limit: 1, period: period_proc) do |request|
+      request.ip
+    end
+
+    # Using Time#at to align to start/end of periods exactly
+    # to achieve consistenty in different test runs
+
+    Timecop.travel(Time.at(0)) do
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      assert_equal 200, last_response.status
+
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      assert_equal 429, last_response.status
+    end
+
+    Timecop.travel(Time.at(10)) do
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      assert_equal 429, last_response.status
+    end
+
+    Timecop.travel(Time.at(30)) do
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      assert_equal 200, last_response.status
+    end
+
+    Timecop.travel(Time.at(0)) do
+      get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+      assert_equal 200, last_response.status
+
+      get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+      assert_equal 429, last_response.status
+    end
+
+    Timecop.travel(Time.at(10)) do
+      get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+      assert_equal 200, last_response.status
+    end
+  end
 end