diff --git a/CHANGELOG.md b/CHANGELOG.md
index 437e43ae..c965fb35 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,14 @@
 
 All notable changes to this project will be documented in this file. See [standard-version](https://github.com/conventional-changelog/standard-version) for commit guidelines.
 
+### [8.1.1](https://github.com/istanbuljs/v8-to-istanbul/compare/v8.1.0...v8.1.1) (2022-01-10)
+
+
+### Bug Fixes
+
+* handle undefined sourcesContent and null sourcesContent entry ([6c2e2ec](https://github.com/istanbuljs/v8-to-istanbul/commit/6c2e2ecd2aece8b01543f75dfa203744f8a785b9))
+* **perf:** optimize hit counting and source map performance ([3f83226](https://github.com/istanbuljs/v8-to-istanbul/commit/3f83226212e9fd26231bb313b36db4f2d0661970)), closes [#159](https://github.com/istanbuljs/v8-to-istanbul/issues/159)
+
 ## [8.1.0](https://www.github.com/istanbuljs/v8-to-istanbul/compare/v8.0.0...v8.1.0) (2021-09-27)
 
 
diff --git a/package-lock.json b/package-lock.json
index 61cd15cf..f0b1a6e1 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "v8-to-istanbul",
-  "version": "8.1.0",
+  "version": "8.1.1",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "v8-to-istanbul",
-      "version": "8.1.0",
+      "version": "8.1.1",
       "license": "ISC",
       "dependencies": {
         "@types/istanbul-lib-coverage": "^2.0.1",
diff --git a/package.json b/package.json
index 18b6b625..50abafb4 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "v8-to-istanbul",
-  "version": "8.1.0",
+  "version": "8.1.1",
   "description": "convert from v8 coverage format to istanbul's format",
   "main": "index.js",
   "types": "index.d.ts",