diff --git a/client/pubspec.yaml b/client/pubspec.yaml
index 6345d70..ba9945e 100644
--- a/client/pubspec.yaml
+++ b/client/pubspec.yaml
@@ -2,6 +2,9 @@ name: musicus_client
 description: Client library for the Musicus server.
 version: 0.0.1
 
+environment:
+  sdk: ">=2.3.0 <3.0.0"
+
 dependencies:
   http:
   musicus_database:
diff --git a/server/pubspec.yaml b/server/pubspec.yaml
index 2356dcb..869aeb2 100644
--- a/server/pubspec.yaml
+++ b/server/pubspec.yaml
@@ -2,6 +2,9 @@ name: musicus_server
 description: A server hosting a Musicus database.
 version: 0.0.1
 
+environment:
+  sdk: ">=2.3.0 <3.0.0"
+
 dependencies:
   aqueduct:
   moor_ffi: