diff --git a/Changelog.md b/Changelog.md
index ad51e2de..56ae57d1 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -23,6 +23,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Fixed relationship diagram to prevent linking to unknown symbols.
   #178 by @MattKiazyk.
 
+### Changed
+
+- Changed GitHub Action to use prebuilt Docker image.
+  #185 by @mattt and @MaxDesiatov.
+
 ## [1.0.0-beta.4] - 2020-07-31
 
 ### Added
diff --git a/action.yml b/action.yml
index c0ad7287..46c691e6 100644
--- a/action.yml
+++ b/action.yml
@@ -23,7 +23,7 @@ inputs:
 
 runs:
   using: "docker"
-  image: "Dockerfile"
+  image: "docker://swiftdoc/swift-doc:latest"
   args:
     [
       generate,