diff --git a/CHANGELOG.md b/CHANGELOG.md
index de0ce86..5e9148d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,7 +3,7 @@
 The release notes on GitHub are taken from this file: the section whose
 heading is the version number.
 
-## Unreleased
+## 2.5.6
 
 - Web UI: new Midnight theme (deep navy with cyan and violet, frosted-glass cards), the fifth in the theme picker. All three flow-line palettes and Auto (violet) work with it; the map ramp runs dark to bright. The four existing themes are unchanged.
 
diff --git a/cmd/traffic66/main.go b/cmd/traffic66/main.go
index 950c428..2987255 100644
--- a/cmd/traffic66/main.go
+++ b/cmd/traffic66/main.go
@@ -55,7 +55,7 @@ var version = ""
 // CHANGELOG.md. TestDevVersionMatchesChangelog keeps the two in step: the
 // default used to be a hardcoded 0.1.0-dev, and because nothing checked it
 // it stayed that way for two major versions.
-const devVersion = "2.5.5"
+const devVersion = "2.5.6"
 
 func init() {
 	if version == "" {