diff --git a/recipe_modules/shard_util_v2/api.py b/recipe_modules/shard_util_v2/api.py
index 90e1ec6..2070ba1 100644
--- a/recipe_modules/shard_util_v2/api.py
+++ b/recipe_modules/shard_util_v2/api.py
@@ -184,6 +184,7 @@
       drone_properties.pop('dependencies', None)
       drone_properties.update(build.get('properties', []))
       drone_properties['build'] = build
+      drone_properties['gclient_variables'] = build.get('gclient_variables', {})
       drone_properties['task_name'] = task_name
       # Delete builds property if it exists.
       drone_properties.pop('builds', None)
diff --git a/recipe_modules/shard_util_v2/examples/full.expected/presubmit_led.json b/recipe_modules/shard_util_v2/examples/full.expected/presubmit_led.json
index 5f190dd..769c435 100644
--- a/recipe_modules/shard_util_v2/examples/full.expected/presubmit_led.json
+++ b/recipe_modules/shard_util_v2/examples/full.expected/presubmit_led.json
@@ -56,6 +56,8 @@
       "-p",
       "environment=\"Staging\"",
       "-p",
+      "gclient_variables={}",
+      "-p",
       "git_ref=\"refs/123/master\"",
       "-p",
       "git_url=\"http://abc\"",
@@ -167,6 +169,7 @@
       "@@@STEP_LOG_LINE@proto.output@            },@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"builder_name_suffix\": \"-try\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"environment\": \"Staging\",@@@",
+      "@@@STEP_LOG_LINE@proto.output@            \"gclient_variables\": {},@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_ref\": \"refs/123/master\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_url\": \"http://abc\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"recipe\": \"engine_v2/builder\",@@@",
@@ -214,7 +217,7 @@
       }
     },
     "name": "launch builds.led edit (2)",
-    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    }\n  }\n}",
+    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"gclient_variables\": {},\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    }\n  }\n}",
     "~followup_annotations": [
       "@@@STEP_NEST_LEVEL@1@@@",
       "@@@STEP_LOG_LINE@proto.output@{@@@",
@@ -302,6 +305,7 @@
       "@@@STEP_LOG_LINE@proto.output@            },@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"builder_name_suffix\": \"-try\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"environment\": \"Staging\",@@@",
+      "@@@STEP_LOG_LINE@proto.output@            \"gclient_variables\": {},@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_ref\": \"refs/123/master\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_url\": \"http://abc\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"recipe\": \"engine_v2/builder\",@@@",
@@ -350,7 +354,7 @@
       }
     },
     "name": "launch builds.led edit (3)",
-    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"ios_debug\"\n  }\n}",
+    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"gclient_variables\": {},\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"ios_debug\"\n  }\n}",
     "~followup_annotations": [
       "@@@STEP_NEST_LEVEL@1@@@",
       "@@@STEP_LOG_LINE@proto.output@{@@@",
@@ -438,6 +442,7 @@
       "@@@STEP_LOG_LINE@proto.output@            },@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"builder_name_suffix\": \"-try\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"environment\": \"Staging\",@@@",
+      "@@@STEP_LOG_LINE@proto.output@            \"gclient_variables\": {},@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_ref\": \"refs/123/master\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_url\": \"http://abc\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"recipe\": \"engine_v2/builder\",@@@",
@@ -486,7 +491,7 @@
       }
     },
     "name": "launch builds.led edit (4)",
-    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"ios_debug\"\n  }\n}",
+    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"gclient_variables\": {},\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"ios_debug\"\n  }\n}",
     "~followup_annotations": [
       "@@@STEP_NEST_LEVEL@1@@@",
       "@@@STEP_LOG_LINE@proto.output@{@@@",
@@ -574,6 +579,7 @@
       "@@@STEP_LOG_LINE@proto.output@            },@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"builder_name_suffix\": \"-try\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"environment\": \"Staging\",@@@",
+      "@@@STEP_LOG_LINE@proto.output@            \"gclient_variables\": {},@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_ref\": \"refs/123/master\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_url\": \"http://abc\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"recipe\": \"engine_v2/builder\",@@@",
@@ -622,7 +628,7 @@
       }
     },
     "name": "launch builds.led edit (5)",
-    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"ios_debug\"\n  }\n}",
+    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"gclient_variables\": {},\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"ios_debug\"\n  }\n}",
     "~followup_annotations": [
       "@@@STEP_NEST_LEVEL@1@@@",
       "@@@STEP_LOG_LINE@proto.output@{@@@",
@@ -710,6 +716,7 @@
       "@@@STEP_LOG_LINE@proto.output@            },@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"builder_name_suffix\": \"-try\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"environment\": \"Staging\",@@@",
+      "@@@STEP_LOG_LINE@proto.output@            \"gclient_variables\": {},@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_ref\": \"refs/123/master\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_url\": \"http://abc\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"recipe\": \"engine_v2/builder\",@@@",
@@ -758,7 +765,7 @@
       }
     },
     "name": "launch builds.led edit (6)",
-    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"ios_debug\"\n  }\n}",
+    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"gclient_variables\": {},\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"ios_debug\"\n  }\n}",
     "~followup_annotations": [
       "@@@STEP_NEST_LEVEL@1@@@",
       "@@@STEP_LOG_LINE@proto.output@{@@@",
@@ -865,6 +872,7 @@
       "@@@STEP_LOG_LINE@proto.output@            },@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"builder_name_suffix\": \"-try\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"environment\": \"Staging\",@@@",
+      "@@@STEP_LOG_LINE@proto.output@            \"gclient_variables\": {},@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_ref\": \"refs/123/master\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_url\": \"http://abc\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"recipe\": \"engine_v2/builder\",@@@",
@@ -912,7 +920,7 @@
       }
     },
     "name": "launch builds.led launch",
-    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"buildbucket\": {\n            \"agent\": {\n              \"input\": {\n                \"data\": {\n                  \"kitchen-checkout\": {\n                    \"cas\": {\n                      \"digest\": {\n                        \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                        \"size_bytes\": \"91\"\n                      }\n                    }\n                  }\n                }\n              },\n              \"purposes\": {\n                \"kitchen-checkout\": \"PURPOSE_EXE_PAYLOAD\"\n              }\n            }\n          },\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"ios_debug\"\n  }\n}",
+    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"custom drone builder-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"buildbucket\": {\n            \"agent\": {\n              \"input\": {\n                \"data\": {\n                  \"kitchen-checkout\": {\n                    \"cas\": {\n                      \"digest\": {\n                        \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                        \"size_bytes\": \"91\"\n                      }\n                    }\n                  }\n                }\n              },\n              \"purposes\": {\n                \"kitchen-checkout\": \"PURPOSE_EXE_PAYLOAD\"\n              }\n            }\n          },\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dimensions\": {\n                \"cpu\": \"arm64\"\n              },\n              \"drone_builder_name\": \"custom drone builder\",\n              \"drone_dimensions\": [\n                \"dimension1=abc\"\n              ],\n              \"gn\": [],\n              \"name\": \"ios_debug\",\n              \"ninja\": [\n                \"ios_debug\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"gclient_variables\": {},\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/builder\",\n            \"task_name\": \"ios_debug\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"ios_debug\"\n  }\n}",
     "~followup_annotations": [
       "@@@STEP_NEST_LEVEL@1@@@",
       "@@@STEP_LOG_LINE@json.output@{@@@",
@@ -1508,6 +1516,8 @@
       "-p",
       "environment=\"Staging\"",
       "-p",
+      "gclient_variables={}",
+      "-p",
       "git_ref=\"refs/123/master\"",
       "-p",
       "git_url=\"http://abc\"",
@@ -1623,6 +1633,7 @@
       "@@@STEP_LOG_LINE@proto.output@            },@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"builder_name_suffix\": \"-try\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"environment\": \"Staging\",@@@",
+      "@@@STEP_LOG_LINE@proto.output@            \"gclient_variables\": {},@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_ref\": \"refs/123/master\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"git_url\": \"http://abc\",@@@",
       "@@@STEP_LOG_LINE@proto.output@            \"recipe\": \"engine_v2/tester\",@@@",
@@ -1670,7 +1681,7 @@
       }
     },
     "name": "launch builds (2).led edit (2)",
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     "name": "launch builds (2).led launch",
-    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"Linux Engine Drone-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"buildbucket\": {\n            \"agent\": {\n              \"input\": {\n                \"data\": {\n                  \"kitchen-checkout\": {\n                    \"cas\": {\n                      \"digest\": {\n                        \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                        \"size_bytes\": \"91\"\n                      }\n                    }\n                  }\n                }\n              },\n              \"purposes\": {\n                \"kitchen-checkout\": \"PURPOSE_EXE_PAYLOAD\"\n              }\n            }\n          },\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dependencies\": [\n                \"ios_debug\"\n              ],\n              \"name\": \"felt_test\",\n              \"parameters\": [\n                \"test\"\n              ],\n              \"resolved_deps\": [\n                {\n                  \"ios_debug\": \"bcd\",\n                  \"web_tests\": \"abc\"\n                }\n              ],\n              \"scripts\": [\n                \"out/script.sh\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/tester\",\n            \"task_name\": \"felt_test\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"felt_test\"\n  }\n}",
+    "stdin": "{\n  \"buildbucket\": {\n    \"bbagent_args\": {\n      \"build\": {\n        \"builder\": {\n          \"bucket\": \"try\",\n          \"builder\": \"Linux Engine Drone-try\",\n          \"project\": \"proj\"\n        },\n        \"infra\": {\n          \"buildbucket\": {\n            \"agent\": {\n              \"input\": {\n                \"data\": {\n                  \"kitchen-checkout\": {\n                    \"cas\": {\n                      \"digest\": {\n                        \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                        \"size_bytes\": \"91\"\n                      }\n                    }\n                  }\n                }\n              },\n              \"purposes\": {\n                \"kitchen-checkout\": \"PURPOSE_EXE_PAYLOAD\"\n              }\n            }\n          },\n          \"swarming\": {\n            \"priority\": -20\n          }\n        },\n        \"input\": {\n          \"properties\": {\n            \"$recipe_engine/buildbucket\": {\n              \"build\": {\n                \"builder\": {\n                  \"bucket\": \"try\",\n                  \"builder\": \"try-builder\",\n                  \"project\": \"proj\"\n                },\n                \"createTime\": \"2018-05-25T23:50:17Z\",\n                \"createdBy\": \"project:proj\",\n                \"id\": \"8945511751514863184\",\n                \"infra\": {\n                  \"resultdb\": {\n                    \"invocation\": \"invocations/build:8945511751514863184\"\n                  },\n                  \"swarming\": {\n                    \"priority\": 30.0\n                  }\n                },\n                \"input\": {\n                  \"gerritChanges\": [\n                    {\n                      \"change\": \"123456\",\n                      \"host\": \"github.com\",\n                      \"patchset\": \"7\",\n                      \"project\": \"repo/a\"\n                    }\n                  ],\n                  \"gitilesCommit\": {\n                    \"host\": \"github.com\",\n                    \"id\": \"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\n                    \"project\": \"repo/a\",\n                    \"ref\": \"refs/heads/main\"\n                  }\n                },\n                \"number\": 123.0,\n                \"tags\": [\n                  {\n                    \"key\": \"cq_experimental\",\n                    \"value\": \"false\"\n                  }\n                ]\n              }\n            },\n            \"$recipe_engine/led\": {\n              \"led_run_id\": \"flutter/led/abc_google.com/b9861e3db1034eee460599837221ab468e03bc43f9fd05684a08157fd646abfc\",\n              \"rbe_cas_input\": {\n                \"cas_instance\": \"projects/chromium-swarm/instances/default_instance\",\n                \"digest\": {\n                  \"hash\": \"146d56311043bb141309968d570e23d05a108d13ce2e20b5aeb40a9b95629b3e\",\n                  \"size_bytes\": 91.0\n                }\n              }\n            },\n            \"build\": {\n              \"dependencies\": [\n                \"ios_debug\"\n              ],\n              \"name\": \"felt_test\",\n              \"parameters\": [\n                \"test\"\n              ],\n              \"resolved_deps\": [\n                {\n                  \"ios_debug\": \"bcd\",\n                  \"web_tests\": \"abc\"\n                }\n              ],\n              \"scripts\": [\n                \"out/script.sh\"\n              ]\n            },\n            \"builder_name_suffix\": \"-try\",\n            \"environment\": \"Staging\",\n            \"gclient_variables\": {},\n            \"git_ref\": \"refs/123/master\",\n            \"git_url\": \"http://abc\",\n            \"recipe\": \"engine_v2/tester\",\n            \"task_name\": \"felt_test\",\n            \"tests\": [\n              {\n                \"dependencies\": [\n                  \"ios_debug\"\n                ],\n                \"name\": \"felt_test\",\n                \"parameters\": [\n                  \"test\"\n                ],\n                \"scripts\": [\n                  \"out/script.sh\"\n                ]\n              }\n            ]\n          }\n        }\n      }\n    },\n    \"name\": \"felt_test\"\n  }\n}",
     "~followup_annotations": [
       "@@@STEP_NEST_LEVEL@1@@@",
       "@@@STEP_LOG_LINE@json.output@{@@@",
diff --git a/recipes/engine_v2/builder.py b/recipes/engine_v2/builder.py
index e86e9a4..b78f0a0 100644
--- a/recipes/engine_v2/builder.py
+++ b/recipes/engine_v2/builder.py
@@ -156,6 +156,8 @@
   # with [cache]/builder and will adjust it to start using it consistently.
   env['ENGINE_PATH'] = api.path['cache'].join('builder')
 
+  # Pass gclient_variables to checkout.
+
   api.flutter_bcid.report_stage('fetch')
   if api.monorepo.is_monorepo_ci_build or api.monorepo.is_monorepo_try_build:
     api.repo_util.monorepo_checkout(cache_root, env, env_prefixes)
@@ -242,7 +244,7 @@
   )
 
   build_custom = dict(build)
-  build_custom["gclient_custom_vars"] = {"example_custom_var": True}
+  build_custom["gclient_variables"] = {"example_custom_var": True}
   build_custom["tests"] = []
   yield api.test(
       'dart-internal-flutter', api.properties(build=build, no_goma=True),