diff --git a/what4/CHANGES.md b/what4/CHANGES.md
index 974484c2..892ab402 100644
--- a/what4/CHANGES.md
+++ b/what4/CHANGES.md
@@ -1,4 +1,4 @@
-# next (TBA)
+# 1.5.1 (October 2023)
 
 * Require building with `versions >= 6.0.2`.
 
diff --git a/what4/what4.cabal b/what4/what4.cabal
index c20a85fb..689c4700 100644
--- a/what4/what4.cabal
+++ b/what4/what4.cabal
@@ -1,6 +1,6 @@
 Cabal-version: 2.4
 Name:          what4
-Version:       1.5.0.0.99
+Version:       1.5.1
 Author:        Galois Inc.
 Maintainer:    rscott@galois.com, kquick@galois.com
 Copyright:     (c) Galois, Inc 2014-2023