diff --git a/packages/amm/CHANGELOG.md b/packages/amm/CHANGELOG.md
index d53913f3..0b7bdb64 100644
--- a/packages/amm/CHANGELOG.md
+++ b/packages/amm/CHANGELOG.md
@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.9.1] - 2022-03-16
+
+### Fixed
+
+- Fix peer dependency version of `@hifi/protocol`.
+
 ## [1.9.0] - 2022-03-16
 
 ### Changed
@@ -170,6 +176,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 - First release of the package.
 
+[1.9.1]: https://github.com/hifi-finance/hifi/compare/@hifi/amm@1.9.0...@hifi/amm@1.9.1
 [1.9.0]: https://github.com/hifi-finance/hifi/compare/@hifi/amm@1.8.2...@hifi/amm@1.9.0
 [1.8.2]: https://github.com/hifi-finance/hifi/compare/@hifi/amm@1.8.1...@hifi/amm@1.8.2
 [1.8.1]: https://github.com/hifi-finance/hifi/compare/@hifi/amm@1.8.0...@hifi/amm@1.8.1
diff --git a/packages/amm/package.json b/packages/amm/package.json
index 3b8534c2..8e2a84da 100644
--- a/packages/amm/package.json
+++ b/packages/amm/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@hifi/amm",
   "description": "Dedicated AMM for market-making hTokens",
-  "version": "1.9.0",
+  "version": "1.9.1",
   "author": {
     "name": "Hifi",
     "email": "contact@hifi.finance",
@@ -87,7 +87,7 @@
   ],
   "license": "BUSL-1.1",
   "peerDependencies": {
-    "@hifi/protocol": "workspace:*",
+    "@hifi/protocol": "1.9.0",
     "@prb/contracts": "3.8.0",
     "@prb/math": "2.5.0",
     "ethers": "^5.5.4"
diff --git a/yarn.lock b/yarn.lock
index 6a0df112..e36aed2e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1416,7 +1416,7 @@ __metadata:
     typechain: ^7.0.0
     typescript: ^4.5.5
   peerDependencies:
-    "@hifi/protocol": "workspace:*"
+    "@hifi/protocol": 1.9.0
     "@prb/contracts": 3.8.0
     "@prb/math": 2.5.0
     ethers: ^5.5.4