diff --git a/CHANGELOG.md b/CHANGELOG.md
index 34bc27cdc2..686004c5db 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Changelog
 
+## mdBook 0.4.21
+[92afe9b...8f01d02](https://github.com/rust-lang/mdBook/compare/92afe9b...8f01d02)
+
+### Fixed
+- Fixed an issue where mdBook would fail to compile with Rust nightly-2022-07-22.
+  [#1861](https://github.com/rust-lang/mdBook/pull/1861)
+
 ## mdBook 0.4.20
 [53055e0...da166e0](https://github.com/rust-lang/mdBook/compare/53055e0...da166e0)
 
diff --git a/Cargo.lock b/Cargo.lock
index dd7feff19f..10fae527f7 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -796,7 +796,7 @@ checksum = "a3e378b66a060d48947b590737b30a1be76706c8dd7b8ba0f2fe3989c68a853f"
 
 [[package]]
 name = "mdbook"
-version = "0.4.20"
+version = "0.4.21"
 dependencies = [
  "ammonia",
  "anyhow",
diff --git a/Cargo.toml b/Cargo.toml
index de7ff8c9cf..60472fb786 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "mdbook"
-version = "0.4.20"
+version = "0.4.21"
 authors = [
     "Mathieu David <mathieudavid@mathieudavid.org>",
     "Michael-F-Bryan <michaelfbryan@gmail.com>",
diff --git a/guide/src/continuous-integration.md b/guide/src/continuous-integration.md
index 64764d9a62..c39cb01009 100644
--- a/guide/src/continuous-integration.md
+++ b/guide/src/continuous-integration.md
@@ -21,7 +21,7 @@ A simple approach would be to use the popular `curl` CLI tool to download the ex
 
 ```sh
 mkdir bin
-curl -sSL https://github.com/rust-lang/mdBook/releases/download/v0.4.20/mdbook-v0.4.20-x86_64-unknown-linux-gnu.tar.gz | tar -xz --directory=bin
+curl -sSL https://github.com/rust-lang/mdBook/releases/download/v0.4.21/mdbook-v0.4.21-x86_64-unknown-linux-gnu.tar.gz | tar -xz --directory=bin
 bin/mdbook build
 ```