diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9dedaa27d..49b374d9e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,8 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
+### Fixed
+- [cpp] When fetching them is disabled, still try to find them. ([#478](https://github.com/cucumber/messages/pull/478))
 
 ## [34.0.1] - 2026-07-05
 ### Fixed
diff --git a/cpp/cmake/dependencies.cpm.cmake b/cpp/cmake/dependencies.cpm.cmake
index 5268b1700..b6557a9d8 100644
--- a/cpp/cmake/dependencies.cpm.cmake
+++ b/cpp/cmake/dependencies.cpm.cmake
@@ -36,4 +36,6 @@ if(CUCUMBER_MESSAGES_FETCH_DEPS)
             set(CMAKE_PREFIX_PATH "${CMAKE_PREFIX_PATH}" PARENT_SCOPE)
         endif()
     endif()
+else()
+    find_package(nlohmann_json 3.12.0 REQUIRED)
 endif()