diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index 2b6f978..d9246dd 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "1.9.1"
+  ".": "1.10.0"
 }
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 69711e9..054872b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,13 @@
 
 All notable changes to the project will be documented in this file. This project adheres to [Semantic Versioning](http://semver.org).
 
+## [1.10.0](https://github.com/launchdarkly/eventsource/compare/v1.9.1...v1.10.0) (2025-07-01)
+
+
+### Features
+
+* Add header support ([#53](https://github.com/launchdarkly/eventsource/issues/53)) ([b3a725f](https://github.com/launchdarkly/eventsource/commit/b3a725fa09fb8fb5e6d4ec76483f278809c7f1f4))
+
 ## [1.9.1](https://github.com/launchdarkly/eventsource/compare/v1.9.0...v1.9.1) (2025-06-02)