From 5712ffa6cff3d7cc9b31d10fb35aad10ac747881 Mon Sep 17 00:00:00 2001
From: Igor Unanua <igor.unanua@datadoghq.com>
Date: Mon, 2 Mar 2026 15:08:24 +0100
Subject: [PATCH 1/3] Use a shared cache

---
 .github/workflows/coverage.yml                  | 2 ++
 .github/workflows/fuzz.yml                      | 2 ++
 .github/workflows/lint.yml                      | 4 ++++
 .github/workflows/miri.yml                      | 2 ++
 .github/workflows/pr-metadata-docs-and-deps.yml | 4 ++++
 .github/workflows/pr-title-semver-check.yml     | 2 ++
 .github/workflows/release-proposal-dispatch.yml | 2 ++
 .github/workflows/test.yml                      | 8 ++++++++
 .github/workflows/verify-proto-files.yml        | 2 ++
 9 files changed, 28 insertions(+)

diff --git a/.github/workflows/coverage.yml b/.github/workflows/coverage.yml
index c37c9c663d..fdea9aa0ba 100644
--- a/.github/workflows/coverage.yml
+++ b/.github/workflows/coverage.yml
@@ -37,6 +37,8 @@ jobs:
         with:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
+          shared-key: shared-${{ runner.os }}
+          # save-if: ${{ github.ref == 'refs/heads/main' }}
       - name: Generate code coverage (including doc tests)
         run: |
           cargo llvm-cov --all-features --workspace --no-report nextest
diff --git a/.github/workflows/fuzz.yml b/.github/workflows/fuzz.yml
index a44010700f..c57b7e8121 100644
--- a/.github/workflows/fuzz.yml
+++ b/.github/workflows/fuzz.yml
@@ -26,6 +26,8 @@ jobs:
       with:
         cache-targets: true # cache build artifacts
         cache-bin: true # cache the ~/.cargo/bin directory
+        shared-key: shared-${{ runner.os }}
+        # save-if: ${{ github.ref == 'refs/heads/main' }}
     - run: |
         set -e
         # cargo bolero list outputs {"package":"package-name","test":"test-name"}
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index b33af83d94..614155b137 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -29,6 +29,8 @@ jobs:
         with:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
+          shared-key: shared-${{ runner.os }}
+          # save-if: ${{ github.ref == 'refs/heads/main' }}
       - run: cargo fmt --all -- --check
   clippy:
     name: "clippy #${{ matrix.platform }} ${{ matrix.rust_version }}"
@@ -48,6 +50,8 @@ jobs:
         with:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
+          shared-key: shared-${{ runner.os }}
+          # save-if: ${{ github.ref == 'refs/heads/main' }}
       - name: Run clippy on ${{ matrix.platform }} ${{ matrix.rust_version }}
         shell: bash
         run: |
diff --git a/.github/workflows/miri.yml b/.github/workflows/miri.yml
index ddb8bdbe69..5138f0075f 100644
--- a/.github/workflows/miri.yml
+++ b/.github/workflows/miri.yml
@@ -28,6 +28,8 @@ jobs:
         with:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
+          shared-key: shared-${{ runner.os }}
+          # save-if: ${{ github.ref == 'refs/heads/main' }}
       - run: MIRIFLAGS="-Zmiri-disable-isolation" cargo miri nextest run --partition count:${{ matrix.partition }}/5
       # We need to disable isolation because
       # "unsupported operation: `clock_gettime` with `REALTIME` clocks not available when isolation is enabled"
diff --git a/.github/workflows/pr-metadata-docs-and-deps.yml b/.github/workflows/pr-metadata-docs-and-deps.yml
index 0406c8658c..da350ef094 100644
--- a/.github/workflows/pr-metadata-docs-and-deps.yml
+++ b/.github/workflows/pr-metadata-docs-and-deps.yml
@@ -103,6 +103,8 @@ jobs:
     - uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # v2.8.1
       with:
         cache-targets: true
+        shared-key: shared-${{ runner.os }}
+        # save-if: ${{ github.ref == 'refs/heads/main' }}
     - uses: dtolnay/rust-toolchain@stable
     - name: Check missing docs
       id: missing-docs
@@ -274,6 +276,8 @@ jobs:
     - uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # v2.8.1
       with:
         cache-targets: true
+        shared-key: shared-${{ runner.os }}
+        # save-if: ${{ github.ref == 'refs/heads/main' }}
     - uses: dtolnay/rust-toolchain@stable
     - uses: taiki-e/cache-cargo-install-action@7447f04c51f2ba27ca35e7f1e28fab848c5b3ba7 # 2.3.1
       with:
diff --git a/.github/workflows/pr-title-semver-check.yml b/.github/workflows/pr-title-semver-check.yml
index 288f9dbfd7..48303dac26 100644
--- a/.github/workflows/pr-title-semver-check.yml
+++ b/.github/workflows/pr-title-semver-check.yml
@@ -99,6 +99,8 @@ jobs:
         uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # 2.8.1
         with:
           cache-targets: true
+          shared-key: shared-${{ runner.os }}
+          # save-if: ${{ github.ref == 'refs/heads/main' }}
 
       - name: Install dependencies
         run: |
diff --git a/.github/workflows/release-proposal-dispatch.yml b/.github/workflows/release-proposal-dispatch.yml
index f69e238aa8..9f56b2c3d3 100644
--- a/.github/workflows/release-proposal-dispatch.yml
+++ b/.github/workflows/release-proposal-dispatch.yml
@@ -142,6 +142,8 @@ jobs:
       - uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # v2.8.1
         with:
           cache-targets: true
+          shared-key: shared-${{ runner.os }}
+          # save-if: ${{ github.ref == 'refs/heads/main' }}
       - uses: dtolnay/rust-toolchain@nightly
         with:
           toolchain: nightly-2026-02-08
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 258cefff39..fa3b153404 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -46,11 +46,15 @@ jobs:
         uses: taiki-e/install-action@2c41309d51ede152b6f2ee6bf3b71e6dc9a8b7df # 2.49.27
         with:
           tool: nextest@0.9.96
+      # shared-key = one cache per (OS, lockfile, toolchain) shared across workflows
+      # save-if: main = only save on default branch to avoid filling GH cache with PR runs
       - name: Cache [rust]
         uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # 2.8.1
         with:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
+          shared-key: shared-${{ runner.os }}
+          # save-if: ${{ github.ref == 'refs/heads/main' }}
       - name: "Remove nextest CI report"
         shell: bash
         run: rm -rf target/nextest/ci/junit.xml
@@ -189,6 +193,8 @@ jobs:
         with:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
+          shared-key: shared-${{ runner.os }}
+          # save-if: ${{ github.ref == 'refs/heads/main' }}
       - name: "Generate profiling FFI"
         shell: bash
         env:
@@ -302,6 +308,8 @@ jobs:
         with:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
+          shared-key: shared-${{ runner.os }}
+          # save-if: ${{ github.ref == 'refs/heads/main' }}
       - run: cargo install cross || true
       - run: cross build --workspace --target x86_64-unknown-linux-gnu --exclude builder
       - run: cross test --workspace --features libdd-crashtracker/generate-unit-test-files --target x86_64-unknown-linux-gnu --exclude builder  -- --skip "::single_threaded_tests::" --skip "tracing_integration_tests::"
diff --git a/.github/workflows/verify-proto-files.yml b/.github/workflows/verify-proto-files.yml
index 0e7b570bdc..57933ce04d 100644
--- a/.github/workflows/verify-proto-files.yml
+++ b/.github/workflows/verify-proto-files.yml
@@ -52,6 +52,8 @@ jobs:
         with:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
+          shared-key: shared-${{ runner.os }}
+          # save-if: ${{ github.ref == 'refs/heads/main' }}
       - name: diff pb.rs
         working-directory: libdd-trace-protobuf
         run: |

From 9af709c610d9f42d5b5c970d441ba163ced83be1 Mon Sep 17 00:00:00 2001
From: Igor Unanua <igor.unanua@datadoghq.com>
Date: Tue, 3 Mar 2026 16:49:10 +0100
Subject: [PATCH 2/3] save-if main

---
 .github/workflows/coverage.yml                  | 2 +-
 .github/workflows/fuzz.yml                      | 2 +-
 .github/workflows/lint.yml                      | 4 ++--
 .github/workflows/miri.yml                      | 2 +-
 .github/workflows/pr-metadata-docs-and-deps.yml | 4 ++--
 .github/workflows/pr-title-semver-check.yml     | 2 +-
 .github/workflows/release-proposal-dispatch.yml | 2 +-
 .github/workflows/test.yml                      | 6 +++---
 .github/workflows/verify-proto-files.yml        | 2 +-
 9 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/.github/workflows/coverage.yml b/.github/workflows/coverage.yml
index fdea9aa0ba..ec8a92f321 100644
--- a/.github/workflows/coverage.yml
+++ b/.github/workflows/coverage.yml
@@ -38,7 +38,7 @@ jobs:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
           shared-key: shared-${{ runner.os }}
-          # save-if: ${{ github.ref == 'refs/heads/main' }}
+          save-if: ${{ github.ref == 'refs/heads/main' }}
       - name: Generate code coverage (including doc tests)
         run: |
           cargo llvm-cov --all-features --workspace --no-report nextest
diff --git a/.github/workflows/fuzz.yml b/.github/workflows/fuzz.yml
index c57b7e8121..40c323f6c4 100644
--- a/.github/workflows/fuzz.yml
+++ b/.github/workflows/fuzz.yml
@@ -27,7 +27,7 @@ jobs:
         cache-targets: true # cache build artifacts
         cache-bin: true # cache the ~/.cargo/bin directory
         shared-key: shared-${{ runner.os }}
-        # save-if: ${{ github.ref == 'refs/heads/main' }}
+        save-if: ${{ github.ref == 'refs/heads/main' }}
     - run: |
         set -e
         # cargo bolero list outputs {"package":"package-name","test":"test-name"}
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 614155b137..f72ac1c29f 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -30,7 +30,7 @@ jobs:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
           shared-key: shared-${{ runner.os }}
-          # save-if: ${{ github.ref == 'refs/heads/main' }}
+          save-if: ${{ github.ref == 'refs/heads/main' }}
       - run: cargo fmt --all -- --check
   clippy:
     name: "clippy #${{ matrix.platform }} ${{ matrix.rust_version }}"
@@ -51,7 +51,7 @@ jobs:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
           shared-key: shared-${{ runner.os }}
-          # save-if: ${{ github.ref == 'refs/heads/main' }}
+          save-if: ${{ github.ref == 'refs/heads/main' }}
       - name: Run clippy on ${{ matrix.platform }} ${{ matrix.rust_version }}
         shell: bash
         run: |
diff --git a/.github/workflows/miri.yml b/.github/workflows/miri.yml
index 5138f0075f..0cd706b3b3 100644
--- a/.github/workflows/miri.yml
+++ b/.github/workflows/miri.yml
@@ -29,7 +29,7 @@ jobs:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
           shared-key: shared-${{ runner.os }}
-          # save-if: ${{ github.ref == 'refs/heads/main' }}
+          save-if: ${{ github.ref == 'refs/heads/main' }}
       - run: MIRIFLAGS="-Zmiri-disable-isolation" cargo miri nextest run --partition count:${{ matrix.partition }}/5
       # We need to disable isolation because
       # "unsupported operation: `clock_gettime` with `REALTIME` clocks not available when isolation is enabled"
diff --git a/.github/workflows/pr-metadata-docs-and-deps.yml b/.github/workflows/pr-metadata-docs-and-deps.yml
index da350ef094..5b9ec53a65 100644
--- a/.github/workflows/pr-metadata-docs-and-deps.yml
+++ b/.github/workflows/pr-metadata-docs-and-deps.yml
@@ -104,7 +104,7 @@ jobs:
       with:
         cache-targets: true
         shared-key: shared-${{ runner.os }}
-        # save-if: ${{ github.ref == 'refs/heads/main' }}
+        save-if: ${{ github.ref == 'refs/heads/main' }}
     - uses: dtolnay/rust-toolchain@stable
     - name: Check missing docs
       id: missing-docs
@@ -277,7 +277,7 @@ jobs:
       with:
         cache-targets: true
         shared-key: shared-${{ runner.os }}
-        # save-if: ${{ github.ref == 'refs/heads/main' }}
+        save-if: ${{ github.ref == 'refs/heads/main' }}
     - uses: dtolnay/rust-toolchain@stable
     - uses: taiki-e/cache-cargo-install-action@7447f04c51f2ba27ca35e7f1e28fab848c5b3ba7 # 2.3.1
       with:
diff --git a/.github/workflows/pr-title-semver-check.yml b/.github/workflows/pr-title-semver-check.yml
index 48303dac26..a510027de4 100644
--- a/.github/workflows/pr-title-semver-check.yml
+++ b/.github/workflows/pr-title-semver-check.yml
@@ -100,7 +100,7 @@ jobs:
         with:
           cache-targets: true
           shared-key: shared-${{ runner.os }}
-          # save-if: ${{ github.ref == 'refs/heads/main' }}
+          save-if: ${{ github.ref == 'refs/heads/main' }}
 
       - name: Install dependencies
         run: |
diff --git a/.github/workflows/release-proposal-dispatch.yml b/.github/workflows/release-proposal-dispatch.yml
index 9f56b2c3d3..8488b50b19 100644
--- a/.github/workflows/release-proposal-dispatch.yml
+++ b/.github/workflows/release-proposal-dispatch.yml
@@ -143,7 +143,7 @@ jobs:
         with:
           cache-targets: true
           shared-key: shared-${{ runner.os }}
-          # save-if: ${{ github.ref == 'refs/heads/main' }}
+          save-if: ${{ github.ref == 'refs/heads/main' }}
       - uses: dtolnay/rust-toolchain@nightly
         with:
           toolchain: nightly-2026-02-08
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index fa3b153404..126878a5d7 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -54,7 +54,7 @@ jobs:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
           shared-key: shared-${{ runner.os }}
-          # save-if: ${{ github.ref == 'refs/heads/main' }}
+          save-if: ${{ github.ref == 'refs/heads/main' }}
       - name: "Remove nextest CI report"
         shell: bash
         run: rm -rf target/nextest/ci/junit.xml
@@ -194,7 +194,7 @@ jobs:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
           shared-key: shared-${{ runner.os }}
-          # save-if: ${{ github.ref == 'refs/heads/main' }}
+          save-if: ${{ github.ref == 'refs/heads/main' }}
       - name: "Generate profiling FFI"
         shell: bash
         env:
@@ -309,7 +309,7 @@ jobs:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
           shared-key: shared-${{ runner.os }}
-          # save-if: ${{ github.ref == 'refs/heads/main' }}
+          save-if: ${{ github.ref == 'refs/heads/main' }}
       - run: cargo install cross || true
       - run: cross build --workspace --target x86_64-unknown-linux-gnu --exclude builder
       - run: cross test --workspace --features libdd-crashtracker/generate-unit-test-files --target x86_64-unknown-linux-gnu --exclude builder  -- --skip "::single_threaded_tests::" --skip "tracing_integration_tests::"
diff --git a/.github/workflows/verify-proto-files.yml b/.github/workflows/verify-proto-files.yml
index 57933ce04d..9b6db0faad 100644
--- a/.github/workflows/verify-proto-files.yml
+++ b/.github/workflows/verify-proto-files.yml
@@ -53,7 +53,7 @@ jobs:
           cache-targets: true # cache build artifacts
           cache-bin: true # cache the ~/.cargo/bin directory
           shared-key: shared-${{ runner.os }}
-          # save-if: ${{ github.ref == 'refs/heads/main' }}
+          save-if: ${{ github.ref == 'refs/heads/main' }}
       - name: diff pb.rs
         working-directory: libdd-trace-protobuf
         run: |

From e0703d7d6ec7b55487c6549b010024335b5afca0 Mon Sep 17 00:00:00 2001
From: Igor Unanua <igor.unanua@datadoghq.com>
Date: Tue, 3 Mar 2026 17:05:51 +0100
Subject: [PATCH 3/3] remove comment

---
 .github/workflows/test.yml | 2 --
 1 file changed, 2 deletions(-)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 126878a5d7..45bcbc5e1b 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -46,8 +46,6 @@ jobs:
         uses: taiki-e/install-action@2c41309d51ede152b6f2ee6bf3b71e6dc9a8b7df # 2.49.27
         with:
           tool: nextest@0.9.96
-      # shared-key = one cache per (OS, lockfile, toolchain) shared across workflows
-      # save-if: main = only save on default branch to avoid filling GH cache with PR runs
       - name: Cache [rust]
         uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # 2.8.1
         with: