diff --git a/pubspec.yaml b/pubspec.yaml
index d17601a..f6a433b 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,10 +1,10 @@
 name: dartssh2
-version: 2.9.0-pre
+version: 2.9.1-pre
 description: SSH and SFTP client written in pure Dart, aiming to be feature-rich as well as easy to use.
 homepage: https://github.com/TerminalStudio/dartssh2
 
 environment:
-  sdk: ">=2.15.0 <3.0.0"
+  sdk: ">=2.17.0 <3.0.0"
 
 dependencies:
   asn1lib: ^1.0.0