diff --git a/build_daemon/CHANGELOG.md b/build_daemon/CHANGELOG.md
index 7d35a7b96..dfe8c24f4 100644
--- a/build_daemon/CHANGELOG.md
+++ b/build_daemon/CHANGELOG.md
@@ -1,3 +1,9 @@
+# 2.1.5-dev
+
+- Allow the null safe built_collection, and built_value, but keep the old
+  built_value_generator and generated code which is compatible across both
+  versions of the core libs.
+
 # 2.1.4
 
 - Remove dependency on `package:package_resolver`.
diff --git a/build_daemon/pubspec.yaml b/build_daemon/pubspec.yaml
index 0129fcd91..97398209f 100644
--- a/build_daemon/pubspec.yaml
+++ b/build_daemon/pubspec.yaml
@@ -1,5 +1,5 @@
 name: build_daemon
-version: 2.1.4
+version: 2.1.5-dev
 description: A daemon for running Dart builds.
 homepage: https://github.com/dart-lang/build/tree/master/build_daemon
 
@@ -7,8 +7,8 @@ environment:
   sdk: ">=2.9.0 <3.0.0"
 
 dependencies:
-  built_collection: ^4.1.0
-  built_value: ^7.0.0
+  built_collection: '>=4.1.0 <6.0.0'
+  built_value: '>=7.0.0 <9.0.0'
   http_multi_server: ^2.0.0
   logging: ^0.11.0
   pedantic: ^1.0.0