diff --git a/CHANGELOG b/CHANGELOG
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,7 @@
+2025-09-07
+        * Version bump (4.5.1). (#666)
+        * Add hello world example for FPGA. (#657)
+
 2025-07-07
         * Version bump (4.5). (#642)
 
diff --git a/copilot.cabal b/copilot.cabal
--- a/copilot.cabal
+++ b/copilot.cabal
@@ -1,5 +1,5 @@
 name:                copilot
-version:             4.5
+version:             4.5.1
 cabal-version:       >= 1.10
 license:             BSD3
 license-file:        LICENSE
@@ -52,12 +52,12 @@
                      , directory             >= 1.3  && < 1.4
                      , filepath              >= 1.4  && < 1.6
 
-                     , copilot-core          >= 4.5 && < 4.6
-                     , copilot-theorem       >= 4.5 && < 4.6
-                     , copilot-language      >= 4.5 && < 4.6
-                     , copilot-libraries     >= 4.5 && < 4.6
-                     , copilot-c99           >= 4.5 && < 4.6
-                     , copilot-prettyprinter >= 4.5 && < 4.6
+                     , copilot-core          >= 4.5.1 && < 4.6
+                     , copilot-theorem       >= 4.5.1 && < 4.6
+                     , copilot-language      >= 4.5.1 && < 4.6
+                     , copilot-libraries     >= 4.5.1 && < 4.6
+                     , copilot-c99           >= 4.5.1 && < 4.6
+                     , copilot-prettyprinter >= 4.5.1 && < 4.6
 
 
     exposed-modules: Language.Copilot, Language.Copilot.Main