From b185799446e79bc141318ca5d2fcf901c87d5739 Mon Sep 17 00:00:00 2001
From: "Brian J. Cardiff" <bcardiff@manas.com.ar>
Date: Wed, 22 Feb 2017 13:41:18 -0300
Subject: [PATCH] fix build deferring agent initialization

ref #3988
---
 src/compiler/crystal/tools/playground/server.cr | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/compiler/crystal/tools/playground/server.cr b/src/compiler/crystal/tools/playground/server.cr
index b0f46d1f69d0..e1139d35f136 100644
--- a/src/compiler/crystal/tools/playground/server.cr
+++ b/src/compiler/crystal/tools/playground/server.cr
@@ -23,10 +23,8 @@ module Crystal::Playground
         require "compiler/crystal/tools/playground/agent"
 
         class Crystal::Playground::Agent
-          @@instance = Crystal::Playground::Agent.new("ws://localhost:#{port}/agent/#{session_key}/#{tag}", #{tag})
-
           def self.instance
-            @@instance
+            @@instance ||= Crystal::Playground::Agent.new("ws://localhost:#{port}/agent/#{session_key}/#{tag}", #{tag})
           end
         end