diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 4ce239fd..627f0da7 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -22,6 +22,13 @@ env:
   NUGET_FEED: https://api.nuget.org/v3/index.json
   NUGET_KEY: ${{ secrets.NUGET_KEY }}
 
+# Kill other jobs when we trigger this workflow by sending new commits
+# to the PR.
+# https://stackoverflow.com/a/72408109
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ${{ matrix.os }}