diff --git a/.coveralls.yml b/.coveralls.yml
deleted file mode 100644
index 5d03fa3..0000000
--- a/.coveralls.yml
+++ /dev/null
@@ -1,2 +0,0 @@
-service-name: github
-repo_token: 5JHbEro1j0uJyxWvQSF67Ds1U6UPHyOmj
diff --git a/.github/workflows/coveralls.yml b/.github/workflows/coveralls.yml
index 8dd184f..7bd5fcd 100644
--- a/.github/workflows/coveralls.yml
+++ b/.github/workflows/coveralls.yml
@@ -1,14 +1,19 @@
 # Check the test coverage of the code.
 #
-# This runs as a Github Action.
+# This runs as a Github Action. Note that the Coverall repository token is
+# injected as an environment variable, instead of being read from
+#`.coveralls.yaml` config file.
 #
 # See https://github.com/marketplace/actions/coveralls-github-action
+#
+# Also see
 
 name: Test Coveralls
 on: ["push", "pull_request"]
 
 env:
   COVERAGE: true
+  COVERALLS_REPO_TOKEN: ${{ secrets.COVERALLS_REPO_TOKEN }}
 
 jobs:
   test: