diff --git a/Makefile b/Makefile
index 607a206d..91b36eb6 100644
--- a/Makefile
+++ b/Makefile
@@ -2,7 +2,7 @@
 
 PROJECT = cowboy
 PROJECT_DESCRIPTION = Small, fast, modular HTTP server.
-PROJECT_VERSION = 2.0.0-pre.2
+PROJECT_VERSION = 2.0.0-pre.4
 PROJECT_REGISTERED = cowboy_clock
 
 # Options.
@@ -11,7 +11,7 @@ COMPILE_FIRST = cowboy_middleware cowboy_stream cowboy_sub_protocol
 PLT_APPS = public_key ssl
 CT_OPTS += -ct_hooks cowboy_ct_hook [] # -boot start_sasl
 
-CI_OTP = OTP-18.0.3 OTP-18.1.5 OTP-18.2.2
+CI_OTP = OTP-18.0.3 OTP-18.1.5 OTP-18.2.4.1 OTP-18.3.3 OTP-19.0
 
 # Dependencies.