diff --git a/.ci_extras/pin-crate-vers-kani.sh b/.ci_extras/pin-crate-vers-kani.sh
new file mode 100755
index 00000000..7e7e366a
--- /dev/null
+++ b/.ci_extras/pin-crate-vers-kani.sh
@@ -0,0 +1,8 @@
+#!/bin/sh
+
+set -eux
+
+# Pin some dependencies to specific versions for the nightly toolchain
+# used by Kani verifier.
+cargo update -p syn@2.0 --precise 2.0.58
+cargo update -p proc-macro2 --precise 1.0.79
diff --git a/.github/workflows/Kani.yml b/.github/workflows/Kani.yml
index fe3be086..0c47f6a8 100644
--- a/.github/workflows/Kani.yml
+++ b/.github/workflows/Kani.yml
@@ -43,6 +43,12 @@ jobs:
           lscpu
           free -m
 
+      - name: Pin some dependencies to specific versions
+        run: ./.ci_extras/pin-crate-vers-kani.sh
+
+      - name: Show cargo tree
+        run: cargo tree
+
       - name: Run Kani
         uses: model-checking/kani-github-action@v1.0
         with: