Sign the cosign binary using the email of the service account, instead of using a kms key

Bug: https://b.corp.google.com/issues/240430539

Change-Id: Ib67500e2c9106cd046cb6605e3fb240e84141358
Reviewed-on: https://flutter-review.googlesource.com/c/recipes/+/32183
Reviewed-by: Godofredo Contreras <godofredoc@google.com>
Commit-Queue: Drew Roen <drewroen@google.com>
Reviewed-by: Jesse Seales <jseales@google.com>
diff --git a/recipes/packaging/packaging.expected/linux_beta_cosign.json b/recipes/packaging/packaging.expected/linux_beta_cosign.json
index b147d67..2baef77 100644
--- a/recipes/packaging/packaging.expected/linux_beta_cosign.json
+++ b/recipes/packaging/packaging.expected/linux_beta_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -625,6 +629,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -675,6 +680,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -726,6 +732,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -774,6 +781,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -816,11 +824,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/linux_beta_experimental_cosign.json b/recipes/packaging/packaging.expected/linux_beta_experimental_cosign.json
index d93a1fe..80cc8a4 100644
--- a/recipes/packaging/packaging.expected/linux_beta_experimental_cosign.json
+++ b/recipes/packaging/packaging.expected/linux_beta_experimental_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -624,6 +628,7 @@
       "--branch=beta"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -674,6 +679,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -725,6 +731,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -773,6 +780,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -815,11 +823,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/linux_beta_experimental_upload_cosign.json b/recipes/packaging/packaging.expected/linux_beta_experimental_upload_cosign.json
index d93a1fe..80cc8a4 100644
--- a/recipes/packaging/packaging.expected/linux_beta_experimental_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/linux_beta_experimental_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -624,6 +628,7 @@
       "--branch=beta"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -674,6 +679,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -725,6 +731,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -773,6 +780,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -815,11 +823,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/linux_beta_upload_cosign.json b/recipes/packaging/packaging.expected/linux_beta_upload_cosign.json
index b147d67..2baef77 100644
--- a/recipes/packaging/packaging.expected/linux_beta_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/linux_beta_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -625,6 +629,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -675,6 +680,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -726,6 +732,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -774,6 +781,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -816,11 +824,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/linux_stable_cosign.json b/recipes/packaging/packaging.expected/linux_stable_cosign.json
index 9a61255..07d7bf3 100644
--- a/recipes/packaging/packaging.expected/linux_stable_cosign.json
+++ b/recipes/packaging/packaging.expected/linux_stable_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -625,6 +629,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -675,6 +680,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -726,6 +732,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -774,6 +781,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -816,11 +824,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/linux_stable_experimental_cosign.json b/recipes/packaging/packaging.expected/linux_stable_experimental_cosign.json
index ab9e131..176621a 100644
--- a/recipes/packaging/packaging.expected/linux_stable_experimental_cosign.json
+++ b/recipes/packaging/packaging.expected/linux_stable_experimental_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -624,6 +628,7 @@
       "--branch=stable"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -674,6 +679,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -725,6 +731,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -773,6 +780,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -815,11 +823,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/linux_stable_experimental_upload_cosign.json b/recipes/packaging/packaging.expected/linux_stable_experimental_upload_cosign.json
index ab9e131..176621a 100644
--- a/recipes/packaging/packaging.expected/linux_stable_experimental_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/linux_stable_experimental_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -624,6 +628,7 @@
       "--branch=stable"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -674,6 +679,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -725,6 +731,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -773,6 +780,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -815,11 +823,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/linux_stable_upload_cosign.json b/recipes/packaging/packaging.expected/linux_stable_upload_cosign.json
index 9a61255..07d7bf3 100644
--- a/recipes/packaging/packaging.expected/linux_stable_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/linux_stable_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -625,6 +629,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -675,6 +680,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -726,6 +732,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -774,6 +781,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -816,11 +824,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/mac_beta_cosign.json b/recipes/packaging/packaging.expected/mac_beta_cosign.json
index d22d28b..dd3630c 100644
--- a/recipes/packaging/packaging.expected/mac_beta_cosign.json
+++ b/recipes/packaging/packaging.expected/mac_beta_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -625,6 +629,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -675,6 +680,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -726,6 +732,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -774,6 +781,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -816,11 +824,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/mac_beta_experimental_cosign.json b/recipes/packaging/packaging.expected/mac_beta_experimental_cosign.json
index ae3bf20..9fcaf05 100644
--- a/recipes/packaging/packaging.expected/mac_beta_experimental_cosign.json
+++ b/recipes/packaging/packaging.expected/mac_beta_experimental_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -624,6 +628,7 @@
       "--branch=beta"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -674,6 +679,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -725,6 +731,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -773,6 +780,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -815,11 +823,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/mac_beta_experimental_upload_cosign.json b/recipes/packaging/packaging.expected/mac_beta_experimental_upload_cosign.json
index ae3bf20..9fcaf05 100644
--- a/recipes/packaging/packaging.expected/mac_beta_experimental_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/mac_beta_experimental_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -624,6 +628,7 @@
       "--branch=beta"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -674,6 +679,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -725,6 +731,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -773,6 +780,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -815,11 +823,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/mac_beta_upload_cosign.json b/recipes/packaging/packaging.expected/mac_beta_upload_cosign.json
index d22d28b..dd3630c 100644
--- a/recipes/packaging/packaging.expected/mac_beta_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/mac_beta_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -625,6 +629,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -675,6 +680,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -726,6 +732,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -774,6 +781,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -816,11 +824,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/mac_stable_cosign.json b/recipes/packaging/packaging.expected/mac_stable_cosign.json
index baab111..7d7ac4c 100644
--- a/recipes/packaging/packaging.expected/mac_stable_cosign.json
+++ b/recipes/packaging/packaging.expected/mac_stable_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -625,6 +629,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -675,6 +680,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -726,6 +732,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -774,6 +781,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -816,11 +824,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/mac_stable_experimental_cosign.json b/recipes/packaging/packaging.expected/mac_stable_experimental_cosign.json
index 85c6b5a..30aaa0c 100644
--- a/recipes/packaging/packaging.expected/mac_stable_experimental_cosign.json
+++ b/recipes/packaging/packaging.expected/mac_stable_experimental_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -624,6 +628,7 @@
       "--branch=stable"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -674,6 +679,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -725,6 +731,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -773,6 +780,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -815,11 +823,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/mac_stable_experimental_upload_cosign.json b/recipes/packaging/packaging.expected/mac_stable_experimental_upload_cosign.json
index 85c6b5a..30aaa0c 100644
--- a/recipes/packaging/packaging.expected/mac_stable_experimental_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/mac_stable_experimental_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -624,6 +628,7 @@
       "--branch=stable"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -674,6 +679,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -725,6 +731,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -773,6 +780,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -815,11 +823,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/mac_stable_upload_cosign.json b/recipes/packaging/packaging.expected/mac_stable_upload_cosign.json
index baab111..7d7ac4c 100644
--- a/recipes/packaging/packaging.expected/mac_stable_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/mac_stable_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]/archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -625,6 +629,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -675,6 +680,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -726,6 +732,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -774,6 +781,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -816,11 +824,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/win_beta_cosign.json b/recipes/packaging/packaging.expected/win_beta_cosign.json
index 356ea42..fe9b707 100644
--- a/recipes/packaging/packaging.expected/win_beta_cosign.json
+++ b/recipes/packaging/packaging.expected/win_beta_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -629,6 +633,7 @@
       "/path/to/tmp/json"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -690,6 +695,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -741,6 +747,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -793,6 +800,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -842,6 +850,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -885,11 +894,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/win_beta_experimental_cosign.json b/recipes/packaging/packaging.expected/win_beta_experimental_cosign.json
index b656a69..c7bd1b8 100644
--- a/recipes/packaging/packaging.expected/win_beta_experimental_cosign.json
+++ b/recipes/packaging/packaging.expected/win_beta_experimental_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -629,6 +633,7 @@
       "/path/to/tmp/json"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -689,6 +694,7 @@
       "--branch=beta"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -740,6 +746,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -792,6 +799,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -841,6 +849,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -884,11 +893,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/win_beta_experimental_upload_cosign.json b/recipes/packaging/packaging.expected/win_beta_experimental_upload_cosign.json
index b656a69..c7bd1b8 100644
--- a/recipes/packaging/packaging.expected/win_beta_experimental_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/win_beta_experimental_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -629,6 +633,7 @@
       "/path/to/tmp/json"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -689,6 +694,7 @@
       "--branch=beta"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -740,6 +746,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -792,6 +799,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -841,6 +849,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -884,11 +893,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/win_beta_upload_cosign.json b/recipes/packaging/packaging.expected/win_beta_upload_cosign.json
index 356ea42..fe9b707 100644
--- a/recipes/packaging/packaging.expected/win_beta_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/win_beta_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -629,6 +633,7 @@
       "/path/to/tmp/json"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -690,6 +695,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -741,6 +747,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -793,6 +800,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -842,6 +850,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -885,11 +894,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/beta/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/win_stable_cosign.json b/recipes/packaging/packaging.expected/win_stable_cosign.json
index 1bef79f..6571045 100644
--- a/recipes/packaging/packaging.expected/win_stable_cosign.json
+++ b/recipes/packaging/packaging.expected/win_stable_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -629,6 +633,7 @@
       "/path/to/tmp/json"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -690,6 +695,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -741,6 +747,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -793,6 +800,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -842,6 +850,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -885,11 +894,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/win_stable_experimental_cosign.json b/recipes/packaging/packaging.expected/win_stable_experimental_cosign.json
index 9abca54..a0f9e53 100644
--- a/recipes/packaging/packaging.expected/win_stable_experimental_cosign.json
+++ b/recipes/packaging/packaging.expected/win_stable_experimental_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -629,6 +633,7 @@
       "/path/to/tmp/json"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -689,6 +694,7 @@
       "--branch=stable"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -740,6 +746,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -792,6 +799,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -841,6 +849,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -884,11 +893,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/win_stable_experimental_upload_cosign.json b/recipes/packaging/packaging.expected/win_stable_experimental_upload_cosign.json
index 9abca54..a0f9e53 100644
--- a/recipes/packaging/packaging.expected/win_stable_experimental_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/win_stable_experimental_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -629,6 +633,7 @@
       "/path/to/tmp/json"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -689,6 +694,7 @@
       "--branch=stable"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -740,6 +746,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -792,6 +799,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -841,6 +849,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -884,11 +893,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.expected/win_stable_upload_cosign.json b/recipes/packaging/packaging.expected/win_stable_upload_cosign.json
index 1bef79f..6571045 100644
--- a/recipes/packaging/packaging.expected/win_stable_upload_cosign.json
+++ b/recipes/packaging/packaging.expected/win_stable_upload_cosign.json
@@ -431,6 +431,7 @@
       "doctor"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -475,6 +476,7 @@
       "update-packages"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -524,6 +526,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -576,6 +579,7 @@
       "[START_DIR]\\archive"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -629,6 +633,7 @@
       "/path/to/tmp/json"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -690,6 +695,7 @@
       "--publish"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -741,6 +747,7 @@
       "*flutter*.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -793,6 +800,7 @@
       "us-docker.pkg.dev"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -842,6 +850,7 @@
       "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
@@ -885,11 +894,11 @@
     "cmd": [
       "cosign",
       "sign",
-      "--key",
-      "gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2",
-      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz"
+      "us-docker.pkg.dev/flutter-dashboard-dev/flutter-artifacts/stable/deadbeef/flutter-archive-package.tar.xz",
+      "--force"
     ],
     "env": {
+      "COSIGN_EXPERIMENTAL": "true",
       "DEPOT_TOOLS": "RECIPE_REPO[depot_tools]",
       "GIT_BRANCH": "",
       "LUCI_BRANCH": "",
diff --git a/recipes/packaging/packaging.py b/recipes/packaging/packaging.py
index 3661d65..d5524ca 100644
--- a/recipes/packaging/packaging.py
+++ b/recipes/packaging/packaging.py
@@ -100,12 +100,12 @@
       artifact_registry_url
   ]
 
+  ## The force parameter bypasses the confirmation prompt from cosign
   cosign_sign_args = [
       'cosign',
       'sign',
-      '--key',
-      'gcpkms://projects/flutter-dashboard-dev/locations/global/keyRings/flutter/cryptoKeys/mykey2',
-      artifact_registry_url
+      artifact_registry_url,
+      '--force'
   ]
   api.step('configure docker registry', gcloud_docker_config_args)
   api.step('upload through cosign', cosign_upload_args)
@@ -136,6 +136,12 @@
         ref='master',
     )
   env, env_prefixes = api.repo_util.flutter_environment(checkout_path)
+
+  # TODO(drewroen): Remove this once cosign supports keyless signing without enabling
+  # experimental features.
+  if api.properties.get('upload_with_cosign') is True:
+    env['COSIGN_EXPERIMENTAL'] = 'true'
+
   api.flutter_deps.required_deps(
       env, env_prefixes, api.properties.get('dependencies', [])
   )