diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 032ba6de..4e350d3d 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -9,6 +9,14 @@ on:
         required: false
         type: string
 
+# One run per branch (and event): a newer push cancels the older run, so on basic / v2 the
+# "latest" release always gets the build of the newest commit, not of the run that finished
+# last (#90). Every manual run has a group of its own: never cancelled, never replaced by
+# another manual run waiting in the same group.
+concurrency:
+  group: ${{ github.event_name == 'workflow_dispatch' && format('manual-{0}', github.run_id) || format('build-{0}-{1}', github.event_name, github.ref) }}
+  cancel-in-progress: ${{ github.event_name != 'workflow_dispatch' }}
+
 jobs:
   # Unit tests and lint; also runs for pull requests from forks (no secrets needed)
   test: