diff --git a/lib/en57/event.rb b/lib/en57/event.rb
index 1ae38a1..b174294 100644
--- a/lib/en57/event.rb
+++ b/lib/en57/event.rb
@@ -5,7 +5,7 @@ require "securerandom"
 module En57
   Event =
     Data.define(:id, :type, :data, :tags) do
-      def initialize(id: SecureRandom.uuid, type:, data: {}, tags: [])
+      def initialize(id: SecureRandom.uuid_v7, type:, data: {}, tags: [])
         super(id:, type:, data:, tags:)
       end
     end
diff --git a/test/test_event.rb b/test/test_event.rb
index d46f7d5..b75bd5d 100644
--- a/test/test_event.rb
+++ b/test/test_event.rb
@@ -6,11 +6,11 @@ module En57
   class TestEvent < Minitest::Test
     cover Event
 
-    def test_generates_uuid_by_default
+    def test_generates_uuid_v7_by_default
       event = Event.new(type: "OrderPlaced")
 
       assert_match(
-        /\A[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}\z/,
+        /\A[0-9a-f]{8}-[0-9a-f]{4}-7[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}\z/,
         event.id,
       )
     end
diff --git a/test/test_integration.rb b/test/test_integration.rb
index 810c303..678a7e5 100644
--- a/test/test_integration.rb
+++ b/test/test_integration.rb
@@ -13,7 +13,7 @@ module En57
       SERVER.shutdown
     end
 
-    def ids = @ids ||= Hash.new { |h, k| h[k] = SecureRandom.uuid }
+    def ids = @ids ||= Hash.new { |h, k| h[k] = SecureRandom.uuid_v7 }
 
     def with_event_store =
       yield EventStore.new(PgRepository.new(CONNECTION, JsonSerializer.new))
diff --git a/test/test_pg_repository.rb b/test/test_pg_repository.rb
index e671400..dec8789 100644
--- a/test/test_pg_repository.rb
+++ b/test/test_pg_repository.rb
@@ -6,7 +6,7 @@ module En57
   class TestPgRepository < Minitest::Test
     cover PgRepository
 
-    def ids = @ids ||= Hash.new { |h, k| h[k] = SecureRandom.uuid }
+    def ids = @ids ||= Hash.new { |h, k| h[k] = SecureRandom.uuid_v7 }
 
     def array_encoder = @array_encoder ||= PG::TextEncoder::Array.new