diff --git a/project.clj b/project.clj
index 53468fc..5c0eec7 100644
--- a/project.clj
+++ b/project.clj
@@ -1,4 +1,4 @@
-(defproject com.taoensso/nippy "2.15.0-alpha3"
+(defproject com.taoensso/nippy "2.15.0-alpha4"
   :author "Peter Taoussanis <https://www.taoensso.com>"
   :description "High-performance serialization library for Clojure"
   :url "https://github.com/ptaoussanis/nippy"