diff --git a/rebar.config b/rebar.config
index f012197..cf73030 100644
--- a/rebar.config
+++ b/rebar.config
@@ -14,7 +14,7 @@
   {murmur, ".*",
     {git, "https://github.com/lpgauth/murmur.git", {tag, "0.1.0"}}},
   {shackle, ".*",
-    {git, "https://github.com/lpgauth/shackle.git", {tag, "0.5.4"}}}
+    {git, "https://github.com/lpgauth/shackle.git", {tag, "0.6.0"}}}
 ]}.
 
 {edoc_opts, [
diff --git a/rebar.lock b/rebar.lock
index 54ea4e3..9f1f10f 100644
--- a/rebar.lock
+++ b/rebar.lock
@@ -14,5 +14,5 @@
   0},
  {<<"shackle">>,
   {git,"https://github.com/lpgauth/shackle.git",
-       {ref,"2affa3623105a87732140773c9e66d3445f1649b"}},
+       {ref,"d8a837c36f6e675e91b7e78f249f233c78f45cd5"}},
   0}].
diff --git a/src/marina_client.erl b/src/marina_client.erl
index 3acac52..45bb20a 100644
--- a/src/marina_client.erl
+++ b/src/marina_client.erl
@@ -6,7 +6,7 @@
 
 -behavior(shackle_client).
 -export([
-    init/0,
+    init/1,
     setup/2,
     handle_request/2,
     handle_data/2,
@@ -22,10 +22,10 @@
 -type state() :: #state {}.
 
 %% shackle_server callbacks
--spec init() ->
+-spec init(undefined) ->
     {ok, state()}.
 
-init() ->
+init(_Opts) ->
     {ok, #state {
         frame_flags = marina_utils:frame_flags()
     }}.