diff --git a/post_test.go b/post_test.go
index a2217dc..d9c087c 100644
--- a/post_test.go
+++ b/post_test.go
@@ -550,3 +550,62 @@ func TestComplexParallelWebmentions(t *testing.T) {
 		t.Errorf("Expected 20 webmentions, got %d", len(outs))
 	}
 }
+func TestComplexParallelSimulatedProcessesWebmentions(t *testing.T) {
+	repoName := testRepoName()
+	repo, _ := owl.CreateRepository(repoName, owl.RepoConfig{})
+	repo.HttpClient = &MockHttpClient{}
+	repo.Parser = &MockParseLinksHtmlParser{
+		Links: []string{
+			"http://example.com/1",
+			"http://example.com/2",
+			"http://example.com/3",
+		},
+	}
+	user, _ := repo.CreateUser("testuser")
+	post, _ := user.CreateNewPost("testpost")
+
+	wg := sync.WaitGroup{}
+	wg.Add(40)
+
+	for i := 0; i < 20; i++ {
+		go func(k int) {
+			defer wg.Done()
+			fRepo, _ := owl.OpenRepository(repoName)
+			fUser, _ := fRepo.GetUser("testuser")
+			fPost, err := fUser.GetPost(post.Id())
+			if err != nil {
+				t.Error(err)
+				return
+			}
+			fPost.AddIncomingWebmention("http://example.com/" + strconv.Itoa(k))
+		}(i)
+		go func(k int) {
+			defer wg.Done()
+			fRepo, _ := owl.OpenRepository(repoName)
+			fUser, _ := fRepo.GetUser("testuser")
+			fPost, err := fUser.GetPost(post.Id())
+			if err != nil {
+				t.Error(err)
+				return
+			}
+			webmention := owl.WebmentionOut{
+				Target: "http://example.com/" + strconv.Itoa(k),
+			}
+			fPost.SendWebmention(webmention)
+		}(i)
+	}
+
+	wg.Wait()
+
+	ins := post.IncomingWebmentions()
+
+	if len(ins) != 20 {
+		t.Errorf("Expected 20 webmentions, got %d", len(ins))
+	}
+
+	outs := post.OutgoingWebmentions()
+
+	if len(outs) != 20 {
+		t.Errorf("Expected 20 webmentions, got %d", len(outs))
+	}
+}