diff --git a/rebar.config b/rebar.config
index a28ea33..7aa7bcc 100644
--- a/rebar.config
+++ b/rebar.config
@@ -1,4 +1,5 @@
 {erl_opts, [warnings_as_errors,
+	    {platform_define, "^2[0-1]{1}", fsm_deprecated},
             {platform_define, "^1[7-8]{1}", old_rand},
             {platform_define, "^R", old_rand},
             {platform_define, "^R", no_sync}]}.
diff --git a/src/leveled_cdb.erl b/src/leveled_cdb.erl
index 431710d..524de3a 100644
--- a/src/leveled_cdb.erl
+++ b/src/leveled_cdb.erl
@@ -46,6 +46,17 @@
 -behaviour(gen_fsm).
 -include("include/leveled.hrl").
 
+
+-ifdef(fsm_deprecated).
+-compile({nowarn_deprecated_function, 
+            [{gen_fsm, start, 3},
+                {gen_fsm, sync_send_event, 3},
+                {gen_fsm, sync_send_event, 2},
+                {gen_fsm, send_event, 2},
+                {gen_fsm, sync_send_all_state_event, 3},
+                {gen_fsm, send_all_state_event, 2}]}).
+-endif.
+
 -export([init/1,
             handle_sync_event/4,
             handle_event/3,
diff --git a/src/leveled_sst.erl b/src/leveled_sst.erl
index 03a0504..fd0638e 100644
--- a/src/leveled_sst.erl
+++ b/src/leveled_sst.erl
@@ -62,6 +62,14 @@
 
 -behaviour(gen_fsm).
 
+-ifdef(fsm_deprecated).
+-compile({nowarn_deprecated_function, 
+            [{gen_fsm, start, 3},
+                {gen_fsm, sync_send_event, 3},
+                {gen_fsm, send_event, 2},
+                {gen_fsm, send_all_state_event, 2}]}).
+-endif.
+
 -include("include/leveled.hrl").
 
 -define(MAX_SLOTS, 256).