update source_maps constraint (#19)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9b9df6a..720b50d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,8 @@
-## 2.1.0
+## 2.10.0-nullsafety.1
+
+* Update source_maps constraint.
+
+## 2.10.0-nullsafety
 
 * Migrate to null safety.
 
diff --git a/pubspec.yaml b/pubspec.yaml
index c867622..cd78eae 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: source_map_stack_trace
-version: 2.1.0-nullsafety
+version: 2.1.0-nullsafety.1
 description: A package for applying source maps to stack traces.
 homepage: https://github.com/dart-lang/source_map_stack_trace
 
@@ -10,7 +10,7 @@
 dependencies:
   path: '>=1.8.0-nullsafety <1.8.0'
   stack_trace: '>=1.10.0-nullsafety <1.10.0'
-  source_maps: '>=0.11.0-nullsafety <0.11.0'
+  source_maps: '>=0.10.10-nullsafety <0.10.10'
 
 dev_dependencies:
   source_span: ^1.6.0