diff --git a/spec/requests/articles/show_spec.cr b/spec/requests/articles/show_spec.cr
new file mode 100644
index 0000000..56ad415
--- /dev/null
+++ b/spec/requests/articles/show_spec.cr
@@ -0,0 +1,71 @@
+require "../../spec_helper"
+
+class TestClient < MediumClient
+  class_property last_post_id : String = ""
+
+  def self.post_data(post_id : String) : PostResponse::Root
+    self.last_post_id = post_id
+    PostResponse::Root.from_json <<-JSON
+      {
+        "data": {
+          "post": {
+            "title": "a title",
+            "createdAt": 0,
+            "creator": { "id": "0", "name": "username" },
+            "content": { "bodyModel": { "paragraphs": [] } }
+          }
+        }
+      }
+    JSON
+  end
+end
+
+class Articles::Show
+  def client_class
+    TestClient
+  end
+end
+
+describe Articles::Show do
+  it "parses the post id for urls like /@user/:post_slug" do
+    HttpClient.get("/@user/my-post-111111abcdef")
+
+    TestClient.last_post_id.should eq("111111abcdef")
+  end
+
+  it "parses the post id for urls like /user/:post_slug" do
+    HttpClient.get("/user/my-post-222222abcdef")
+
+    TestClient.last_post_id.should eq("222222abcdef")
+  end
+
+  it "parses the post id for urls like /p/:post_slug" do
+    HttpClient.get("/p/my-post-333333abcdef")
+
+    TestClient.last_post_id.should eq("333333abcdef")
+  end
+
+  it "parses the post id for urls like /posts/:post_slug" do
+    HttpClient.get("/posts/my-post-444444abcdef")
+
+    TestClient.last_post_id.should eq("444444abcdef")
+  end
+
+  it "parses the post id for urls like /p/:post_id" do
+    HttpClient.get("/p/555555abcdef")
+
+    TestClient.last_post_id.should eq("555555abcdef")
+  end
+
+  it "parses the post id for urls like /:post_slug" do
+    HttpClient.get("/my-post-666666abcdef")
+
+    TestClient.last_post_id.should eq("666666abcdef")
+  end
+
+  it "parses the post id for urls like /https:/medium.com/@user/:post_slug" do
+    HttpClient.get("/https:/medium.com/@user/777777abcdef")
+
+    TestClient.last_post_id.should eq("777777abcdef")
+  end
+end
diff --git a/spec/support/api_client.cr b/spec/support/api_client.cr
deleted file mode 100644
index 6bd08dc..0000000
--- a/spec/support/api_client.cr
+++ /dev/null
@@ -1,6 +0,0 @@
-class ApiClient < Lucky::BaseHTTPClient
-  def initialize
-    super
-    headers("Content-Type": "application/json")
-  end
-end
diff --git a/spec/support/http_client.cr b/spec/support/http_client.cr
new file mode 100644
index 0000000..b25118b
--- /dev/null
+++ b/spec/support/http_client.cr
@@ -0,0 +1,2 @@
+class HttpClient < Lucky::BaseHTTPClient
+end
diff --git a/src/actions/articles/show.cr b/src/actions/articles/show.cr
index 35a66f7..8bf9fa7 100644
--- a/src/actions/articles/show.cr
+++ b/src/actions/articles/show.cr
@@ -1,23 +1,34 @@
 require "json"
 
 class Articles::Show < BrowserAction
-  get "/posts/:post_slug" do
-    id_match = post_slug.match(/([0-9a-f]{12})$/i)
-    if id_match
-      post_id = id_match[1]
-    else
-      return html(
+  fallback do
+    maybe_post_id = post_id(context.request.path)
+    case maybe_post_id
+    in Monads::Just
+      response = client_class.post_data(maybe_post_id.value!)
+      page = PageConverter.new.convert(response.data)
+      html ShowPage, page: page
+    in Monads::Nothing, Monads::Maybe
+      html(
         Errors::ShowPage,
         message: "Error parsing the URL",
         status: 500,
       )
     end
+  end
+
+  def post_id(request_path : String)
+    Monads::Try(Regex::MatchData)
+      .new(->{ request_path.match(/([0-9a-f]+)$/i) })
+      .to_maybe
+      .fmap(->(matches : Regex::MatchData) { matches[1] })
+  end
+
+  def client_class
     if Lucky::Env.use_local?
-      response = LocalClient.post_data(post_id)
+      LocalClient
     else
-      response = MediumClient.post_data(post_id)
+      MediumClient
     end
-    page = PageConverter.new.convert(response.data)
-    html ShowPage, page: page
   end
 end