diff --git a/.github/workflows/cargo-deny.yml b/.github/workflows/cargo-deny.yml
index 656c50ef2..bbadb57f9 100644
--- a/.github/workflows/cargo-deny.yml
+++ b/.github/workflows/cargo-deny.yml
@@ -6,6 +6,11 @@ on:
     branches:
       - main
 
+# Cargo's libgit2 transport has been flaky when fetching git dependencies with
+# nested submodules. Prefer the system git CLI across every Cargo invocation.
+env:
+  CARGO_NET_GIT_FETCH_WITH_CLI: "true"
+
 jobs:
   cargo-deny:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/rust-ci.yml b/.github/workflows/rust-ci.yml
index d1d7c0df9..9b50ae403 100644
--- a/.github/workflows/rust-ci.yml
+++ b/.github/workflows/rust-ci.yml
@@ -3,6 +3,11 @@ on:
   pull_request: {}
   workflow_dispatch:
 
+# Cargo's libgit2 transport has been flaky when fetching git dependencies with
+# nested submodules. Prefer the system git CLI across every Cargo invocation.
+env:
+  CARGO_NET_GIT_FETCH_WITH_CLI: "true"
+
 jobs:
   # --- Detect what changed so the fast PR workflow only runs relevant jobs ----
   changed:
diff --git a/.github/workflows/rust-release-argument-comment-lint.yml b/.github/workflows/rust-release-argument-comment-lint.yml
index 94f15af7d..7f5ad01aa 100644
--- a/.github/workflows/rust-release-argument-comment-lint.yml
+++ b/.github/workflows/rust-release-argument-comment-lint.yml
@@ -7,6 +7,11 @@ on:
         required: true
         type: boolean
 
+# Cargo's libgit2 transport has been flaky when fetching git dependencies with
+# nested submodules. Prefer the system git CLI across every Cargo invocation.
+env:
+  CARGO_NET_GIT_FETCH_WITH_CLI: "true"
+
 jobs:
   skip:
     if: ${{ !inputs.publish }}
diff --git a/.github/workflows/rust-release-windows.yml b/.github/workflows/rust-release-windows.yml
index 91887cbe0..f0fd6b90f 100644
--- a/.github/workflows/rust-release-windows.yml
+++ b/.github/workflows/rust-release-windows.yml
@@ -20,6 +20,11 @@ on:
       AZURE_TRUSTED_SIGNING_CERTIFICATE_PROFILE_NAME:
         required: true
 
+# Cargo's libgit2 transport has been flaky when fetching git dependencies with
+# nested submodules. Prefer the system git CLI across every Cargo invocation.
+env:
+  CARGO_NET_GIT_FETCH_WITH_CLI: "true"
+
 jobs:
   build-windows-binaries:
     name: Build Windows binaries - ${{ matrix.runner }} - ${{ matrix.target }} - ${{ matrix.bundle }}
diff --git a/.github/workflows/rusty-v8-release.yml b/.github/workflows/rusty-v8-release.yml
index d98cdb2c4..4b5320dcb 100644
--- a/.github/workflows/rusty-v8-release.yml
+++ b/.github/workflows/rusty-v8-release.yml
@@ -5,6 +5,11 @@ on:
     tags:
       - "rusty-v8-v*.*.*"
 
+# Cargo's libgit2 transport has been flaky when fetching git dependencies with
+# nested submodules. Prefer the system git CLI for Cargo smoke tests.
+env:
+  CARGO_NET_GIT_FETCH_WITH_CLI: "true"
+
 concurrency:
   group: ${{ github.workflow }}::${{ github.ref_name }}
   cancel-in-progress: false
diff --git a/.github/workflows/v8-canary.yml b/.github/workflows/v8-canary.yml
index 6341f218a..71ce5d786 100644
--- a/.github/workflows/v8-canary.yml
+++ b/.github/workflows/v8-canary.yml
@@ -37,6 +37,11 @@ on:
       - "third_party/v8/**"
   workflow_dispatch:
 
+# Cargo's libgit2 transport has been flaky when fetching git dependencies with
+# nested submodules. Prefer the system git CLI for Cargo builds and smoke tests.
+env:
+  CARGO_NET_GIT_FETCH_WITH_CLI: "true"
+
 concurrency:
   group: ${{ github.workflow }}::${{ github.event.pull_request.number > 0 && format('pr-{0}', github.event.pull_request.number) || github.ref_name }}
   cancel-in-progress: ${{ github.ref_name != 'main' }}