diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0656510..fe12357 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -36,4 +36,7 @@
 - Fix sign
 
 ## 2.0.0
-- Add null-safety
\ No newline at end of file
+- Add null-safety
+
+## 2.0.1
+- Updated pointycastle to allow 4.0.0.
\ No newline at end of file
diff --git a/pubspec.yaml b/pubspec.yaml
index eaaf70d..813f2e3 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,13 +1,13 @@
 name: bip32
 description: A BIP32 (https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki) compatible library for Flutter writing by Dart.
-version: 2.0.0
+version: 2.0.1
 homepage: https://github.com/dart-bitcoin/bip32-dart
 
 environment:
   sdk: ">=2.12.0 <3.0.0"
 
 dependencies:
-  pointycastle: ^3.0.1
+  pointycastle: ">=3.0.1 <=4.0.0"
   hex: ^0.2.0
   bs58check: ^1.0.2