diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 22f246ff..206e298f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -57,4 +57,9 @@ jobs:
       - name: Upload coverage data to CodeScene
         if: env.CS_ACCESS_TOKEN
         run: cs-coverage upload --format "lcov" --metric "line-coverage" "lcov.info"
+      - name: Upload coverage data to Codecov
+        # v5.4.3
+        uses: codecov/codecov-action@18283e04ce6e62d37312384ff67231eb8fd56d24
+        with:
+          files: lcov.info
 
diff --git a/docs/multi-layered-testing-strategy.md b/docs/multi-layered-testing-strategy.md
index a02e7d08..d4f0c0a4 100644
--- a/docs/multi-layered-testing-strategy.md
+++ b/docs/multi-layered-testing-strategy.md
@@ -15,6 +15,11 @@ reviewers. This approach ensures that we establish a baseline of correctness
 with simple tests before moving on to the more complex and subtle failure modes
 that can emerge in an asynchronous, high-concurrency system.
 
+Code coverage is measured with `cargo tarpaulin`.  The CI workflow uploads the
+generated `lcov.info` report to Codecov using a pinned version of the Codecov
+GitHub Action (`18283e04ce6e62d37312384ff67231eb8fd56d24`, corresponding to
+v5.4.3) to make coverage visible across pull requests.
+
 ## 2. Layer 1: Foundational Correctness (Unit & Integration)
 
 **Objective:** To verify that each component behaves correctly in isolation and
@@ -473,7 +478,7 @@ workload.
 
 2. **Latency:** The round-trip time for a single message.
 
-3. **Push Latency:** The time from `push_handle.push()` to the client receiving
+3. **Push latency:** The time from `push_handle.push()` to the client receiving
    the frame.
 
 **Measurable Objective:** For small frames on [localhost](http://localhost):