diff --git a/spec/session_spec.cr b/spec/session_spec.cr
index 8d86cf8..1a121d6 100644
--- a/spec/session_spec.cr
+++ b/spec/session_spec.cr
@@ -59,7 +59,6 @@ describe "Session" do
     age = nil
     awesome = nil
     velocity = nil
-    arr = nil
     get "/" do |env|
       sess = env.session
       who = sess["who"]?
@@ -71,7 +70,6 @@ describe "Session" do
       sess["age"] = 2016
       sess["velocity"] = 9999.9
       sess["awesome"] = true
-      sess["arr"] = [1, "Serdar", true, 90000.0]
       "Hello"
     end
 
@@ -84,6 +82,5 @@ describe "Session" do
     age.should eq 2016
     velocity.should eq 9999.9
     awesome.should eq true
-    arr.should eq [1, "Serdar", true, 90000.0]
   end
 end
diff --git a/src/kemal/session.cr b/src/kemal/session.cr
index 96d86bc..4477751 100644
--- a/src/kemal/session.cr
+++ b/src/kemal/session.cr
@@ -16,7 +16,7 @@ module Kemal
   # Sessions are pruned hourly after 48 hours of inactivity.
   class Sessions
     # Session Types are String, Integer, Float and Boolean
-    alias SessionTypes = String | Int32 | Float64 | Bool | Array(String | Int32 | Float64 | Bool)
+    alias SessionTypes = String | Int32 | Float64 | Bool
 
     # In-memory, ephemeral datastore only.
     #