diff --git a/.buildkite/test_areas/basic_correctness.yaml b/.buildkite/test_areas/basic_correctness.yaml
index 0310945b086..1addd47c31b 100644
--- a/.buildkite/test_areas/basic_correctness.yaml
+++ b/.buildkite/test_areas/basic_correctness.yaml
@@ -12,7 +12,6 @@ steps:
   - tests/basic_correctness/test_cpu_offload
   - tests/basic_correctness/test_mem.py
   commands:
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - pytest -v -s basic_correctness/test_mem.py
-  - pytest -v -s basic_correctness/test_basic_correctness.py
-  - pytest -v -s basic_correctness/test_cpu_offload.py
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s basic_correctness/test_mem.py
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s basic_correctness/test_basic_correctness.py
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s basic_correctness/test_cpu_offload.py
diff --git a/.buildkite/test_areas/compile.yaml b/.buildkite/test_areas/compile.yaml
index 01248738d51..7691a92ab7a 100644
--- a/.buildkite/test_areas/compile.yaml
+++ b/.buildkite/test_areas/compile.yaml
@@ -14,8 +14,7 @@ steps:
   - vllm/v1/cudagraph_dispatcher.py
   - tests/compile/correctness_e2e/test_sequence_parallel.py
   commands:
-  - export VLLM_TEST_CLEAN_GPU_MEMORY=1
-  - pytest -v -s tests/compile/correctness_e2e/test_sequence_parallel.py
+  - VLLM_TEST_CLEAN_GPU_MEMORY=1 pytest -v -s tests/compile/correctness_e2e/test_sequence_parallel.py
 
 - label: Sequence Parallel Correctness Tests (2xH100)
   key: sequence-parallel-correctness-tests-2xh100
@@ -25,8 +24,7 @@ steps:
   optional: true
   num_devices: 2
   commands:
-  - export VLLM_TEST_CLEAN_GPU_MEMORY=1
-  - pytest -v -s tests/compile/correctness_e2e/test_sequence_parallel.py
+  - VLLM_TEST_CLEAN_GPU_MEMORY=1 pytest -v -s tests/compile/correctness_e2e/test_sequence_parallel.py
 
 - label: AsyncTP Correctness Tests (2xH100)
   key: asynctp-correctness-tests-2xh100
@@ -36,8 +34,7 @@ steps:
   optional: true
   num_devices: 2
   commands:
-  - export VLLM_TEST_CLEAN_GPU_MEMORY=1
-  - pytest -v -s tests/compile/correctness_e2e/test_async_tp.py
+  - VLLM_TEST_CLEAN_GPU_MEMORY=1 pytest -v -s tests/compile/correctness_e2e/test_async_tp.py
 
 - label: AsyncTP Correctness Tests (B200)
   key: asynctp-correctness-tests-b200
@@ -47,8 +44,7 @@ steps:
   optional: true
   num_devices: 2
   commands:
-  - export VLLM_TEST_CLEAN_GPU_MEMORY=1
-  - pytest -v -s tests/compile/correctness_e2e/test_async_tp.py
+  - VLLM_TEST_CLEAN_GPU_MEMORY=1 pytest -v -s tests/compile/correctness_e2e/test_async_tp.py
 
 - label: Distributed Compile Unit Tests (2xH100)
   key: distributed-compile-unit-tests-2xh100
@@ -61,8 +57,7 @@ steps:
   - vllm/model_executor/layers
   - tests/compile/passes/distributed/
   commands:
-  - export VLLM_TEST_CLEAN_GPU_MEMORY=1
-  - pytest -s -v tests/compile/passes/distributed
+  - VLLM_TEST_CLEAN_GPU_MEMORY=1 pytest -s -v tests/compile/passes/distributed
 
 - label: Fusion and Compile Unit Tests (2xB200)
   key: fusion-and-compile-unit-tests-2xb200
diff --git a/.buildkite/test_areas/distributed.yaml b/.buildkite/test_areas/distributed.yaml
index 8aa41a9a26a..159f9a443f8 100644
--- a/.buildkite/test_areas/distributed.yaml
+++ b/.buildkite/test_areas/distributed.yaml
@@ -32,11 +32,10 @@ steps:
   - tests/entrypoints/openai/test_multi_api_servers.py
   commands:
   # https://github.com/NVIDIA/nccl/issues/1838
-  - export NCCL_CUMEM_HOST_ENABLE=0
-  - TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_async_llm_dp.py
-  - TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_eagle_dp.py
-  - TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_external_lb_dp.py
-  - DP_SIZE=2 pytest -v -s entrypoints/openai/test_multi_api_servers.py
+  - NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_async_llm_dp.py
+  - NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_eagle_dp.py
+  - NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_external_lb_dp.py
+  - NCCL_CUMEM_HOST_ENABLE=0 DP_SIZE=2 pytest -v -s entrypoints/openai/test_multi_api_servers.py
 
 - label: Distributed Compile + RPC Tests (2 GPUs)
   key: distributed-compile-rpc-tests-2-gpus
@@ -56,10 +55,9 @@ steps:
   - tests/entrypoints/llm/test_collective_rpc.py
   commands:
   # https://github.com/NVIDIA/nccl/issues/1838
-  - export NCCL_CUMEM_HOST_ENABLE=0
-  - pytest -v -s entrypoints/llm/test_collective_rpc.py
-  - pytest -v -s ./compile/fullgraph/test_basic_correctness.py
-  - pytest -v -s ./compile/test_wrapper.py
+  - NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s entrypoints/llm/test_collective_rpc.py
+  - NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s ./compile/fullgraph/test_basic_correctness.py
+  - NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s ./compile/test_wrapper.py
 
 - label: Distributed Torchrun + Shutdown Tests (2 GPUs)
   key: distributed-torchrun-shutdown-tests-2-gpus
@@ -78,11 +76,10 @@ steps:
   - tests/v1/worker/test_worker_memory_snapshot.py
   commands:
   # https://github.com/NVIDIA/nccl/issues/1838
-  - export NCCL_CUMEM_HOST_ENABLE=0
-  - VLLM_TEST_SAME_HOST=1 torchrun --nproc-per-node=4 distributed/test_same_node.py | grep 'Same node test passed'
-  - VLLM_TEST_SAME_HOST=1 VLLM_TEST_WITH_DEFAULT_DEVICE_SET=1 torchrun --nproc-per-node=4 distributed/test_same_node.py | grep 'Same node test passed'
-  - CUDA_VISIBLE_DEVICES=0,1 pytest -v -s v1/shutdown
-  - pytest -v -s v1/worker/test_worker_memory_snapshot.py
+  - NCCL_CUMEM_HOST_ENABLE=0 VLLM_TEST_SAME_HOST=1 torchrun --nproc-per-node=4 distributed/test_same_node.py | grep 'Same node test passed'
+  - NCCL_CUMEM_HOST_ENABLE=0 VLLM_TEST_SAME_HOST=1 VLLM_TEST_WITH_DEFAULT_DEVICE_SET=1 torchrun --nproc-per-node=4 distributed/test_same_node.py | grep 'Same node test passed'
+  - NCCL_CUMEM_HOST_ENABLE=0 CUDA_VISIBLE_DEVICES=0,1 pytest -v -s v1/shutdown
+  - NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s v1/worker/test_worker_memory_snapshot.py
 
 - label: Distributed Torchrun + Examples (4 GPUs)
   key: distributed-torchrun-examples-4-gpus
@@ -97,24 +94,23 @@ steps:
   - tests/examples/features/data_parallel/data_parallel_offline.py
   commands:
   # https://github.com/NVIDIA/nccl/issues/1838
-  - export NCCL_CUMEM_HOST_ENABLE=0
   # test with torchrun tp=2 and external_dp=2
-  - torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example.py
+  - NCCL_CUMEM_HOST_ENABLE=0 torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example.py
   # test with torchrun tp=2 and pp=2
-  - PP_SIZE=2 torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example.py
+  - NCCL_CUMEM_HOST_ENABLE=0 PP_SIZE=2 torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example.py
   # test with torchrun tp=4 and dp=1
-  - TP_SIZE=4 torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example_moe.py
+  - NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=4 torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example_moe.py
   # test with torchrun tp=2, pp=2 and dp=1
-  - PP_SIZE=2 TP_SIZE=2 torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example_moe.py
+  - NCCL_CUMEM_HOST_ENABLE=0 PP_SIZE=2 TP_SIZE=2 torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example_moe.py
   # test with torchrun tp=1 and dp=4 with ep
-  - DP_SIZE=4 ENABLE_EP=1 torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example_moe.py
+  - NCCL_CUMEM_HOST_ENABLE=0 DP_SIZE=4 ENABLE_EP=1 torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example_moe.py
   # test with torchrun tp=2 and dp=2 with ep
-  - TP_SIZE=2 DP_SIZE=2 ENABLE_EP=1 torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example_moe.py
+  - NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=2 DP_SIZE=2 ENABLE_EP=1 torchrun --nproc-per-node=4 tests/distributed/test_torchrun_example_moe.py
   # test with internal dp
-  - python3 examples/features/data_parallel/data_parallel_offline.py --enforce-eager
+  - NCCL_CUMEM_HOST_ENABLE=0 python3 examples/features/data_parallel/data_parallel_offline.py --enforce-eager
   # rlhf examples
-  - VLLM_ALLOW_INSECURE_SERIALIZATION=1 python3 examples/rl/rlhf_nccl.py
-  - VLLM_ALLOW_INSECURE_SERIALIZATION=1 python3 examples/rl/rlhf_ipc.py
+  - NCCL_CUMEM_HOST_ENABLE=0 VLLM_ALLOW_INSECURE_SERIALIZATION=1 python3 examples/rl/rlhf_nccl.py
+  - NCCL_CUMEM_HOST_ENABLE=0 VLLM_ALLOW_INSECURE_SERIALIZATION=1 python3 examples/rl/rlhf_ipc.py
 
 - label: Distributed DP Tests (4 GPUs)
   key: distributed-dp-tests-4-gpus
@@ -128,14 +124,13 @@ steps:
   - tests/distributed/test_utils
   commands:
   # https://github.com/NVIDIA/nccl/issues/1838
-  - export NCCL_CUMEM_HOST_ENABLE=0
-  - TP_SIZE=2 DP_SIZE=2 pytest -v -s v1/distributed/test_async_llm_dp.py
-  - TP_SIZE=2 DP_SIZE=2 pytest -v -s v1/distributed/test_eagle_dp.py
-  - TP_SIZE=2 DP_SIZE=2 pytest -v -s v1/distributed/test_external_lb_dp.py
-  - TP_SIZE=1 DP_SIZE=4 pytest -v -s v1/distributed/test_internal_lb_dp.py
-  - TP_SIZE=1 DP_SIZE=4 pytest -v -s v1/distributed/test_hybrid_lb_dp.py
-  - pytest -v -s v1/engine/test_engine_core_client.py::test_kv_cache_events_dp
-  - pytest -v -s distributed/test_utils.py
+  - NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=2 DP_SIZE=2 pytest -v -s v1/distributed/test_async_llm_dp.py
+  - NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=2 DP_SIZE=2 pytest -v -s v1/distributed/test_eagle_dp.py
+  - NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=2 DP_SIZE=2 pytest -v -s v1/distributed/test_external_lb_dp.py
+  - NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=1 DP_SIZE=4 pytest -v -s v1/distributed/test_internal_lb_dp.py
+  - NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=1 DP_SIZE=4 pytest -v -s v1/distributed/test_hybrid_lb_dp.py
+  - NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s v1/engine/test_engine_core_client.py::test_kv_cache_events_dp
+  - NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s distributed/test_utils.py
 
 - label: Distributed Compile + Comm (4 GPUs)
   key: distributed-compile-comm-4-gpus
@@ -151,13 +146,12 @@ steps:
   - tests/distributed/test_multiproc_executor.py
   commands:
   # https://github.com/NVIDIA/nccl/issues/1838
-  - export NCCL_CUMEM_HOST_ENABLE=0
-  - pytest -v -s compile/fullgraph/test_basic_correctness.py
-  - pytest -v -s distributed/test_pynccl.py
-  - pytest -v -s distributed/test_events.py
-  - pytest -v -s distributed/test_symm_mem_allreduce.py
+  - NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s compile/fullgraph/test_basic_correctness.py
+  - NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s distributed/test_pynccl.py
+  - NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s distributed/test_events.py
+  - NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s distributed/test_symm_mem_allreduce.py
   # test multi-node TP with multiproc executor (simulated on single node)
-  - pytest -v -s distributed/test_multiproc_executor.py::test_multiproc_executor_multi_node
+  - NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s distributed/test_multiproc_executor.py::test_multiproc_executor_multi_node
 
 - label: Distributed Tests (8 GPUs)(H100)
   key: distributed-tests-8-gpus-h100
@@ -176,9 +170,8 @@ steps:
 
   commands:
   # https://github.com/NVIDIA/nccl/issues/1838
-  - export NCCL_CUMEM_HOST_ENABLE=0
   # test with torchrun tp=2 and dp=4 with ep
-  - torchrun --nproc-per-node=8 ../examples/features/torchrun/torchrun_dp_example_offline.py --tp-size=2 --pp-size=1 --dp-size=4 --enable-ep
+  - NCCL_CUMEM_HOST_ENABLE=0 torchrun --nproc-per-node=8 ../examples/features/torchrun/torchrun_dp_example_offline.py --tp-size=2 --pp-size=1 --dp-size=4 --enable-ep
 
 - label: Distributed Tests (4 GPUs)(A100)
   key: distributed-tests-4-gpus-a100
@@ -271,9 +264,7 @@ steps:
   - tests/distributed/test_pipeline_parallel.py
   - tests/basic_correctness/test_basic_correctness.py
   commands:
-  - export VLLM_USE_RAY_V2_EXECUTOR_BACKEND=1
-  - export NCCL_CUMEM_HOST_ENABLE=0
-  - pytest -v -s distributed/test_ray_v2_executor.py
-  - pytest -v -s distributed/test_ray_v2_executor_e2e.py
-  - pytest -v -s distributed/test_pipeline_parallel.py -k "ray"
-  - TARGET_TEST_SUITE=L4 pytest -v -s basic_correctness/test_basic_correctness.py -k "ray"
+  - VLLM_USE_RAY_V2_EXECUTOR_BACKEND=1 NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s distributed/test_ray_v2_executor.py
+  - VLLM_USE_RAY_V2_EXECUTOR_BACKEND=1 NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s distributed/test_ray_v2_executor_e2e.py
+  - VLLM_USE_RAY_V2_EXECUTOR_BACKEND=1 NCCL_CUMEM_HOST_ENABLE=0 pytest -v -s distributed/test_pipeline_parallel.py -k "ray"
+  - VLLM_USE_RAY_V2_EXECUTOR_BACKEND=1 NCCL_CUMEM_HOST_ENABLE=0 TARGET_TEST_SUITE=L4 pytest -v -s basic_correctness/test_basic_correctness.py -k "ray"
diff --git a/.buildkite/test_areas/entrypoints.yaml b/.buildkite/test_areas/entrypoints.yaml
index f6307f097d9..40e3916ba5b 100644
--- a/.buildkite/test_areas/entrypoints.yaml
+++ b/.buildkite/test_areas/entrypoints.yaml
@@ -22,10 +22,9 @@ steps:
   - vllm/
   - tests/entrypoints/llm
   commands:
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - pytest -v -s entrypoints/llm --ignore=entrypoints/llm/test_generate.py --ignore=entrypoints/llm/test_collective_rpc.py --ignore=entrypoints/llm/offline_mode
-  - pytest -v -s entrypoints/llm/test_generate.py # it needs a clean process
-  - pytest -v -s entrypoints/llm/offline_mode # Needs to avoid interference with other tests
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/llm --ignore=entrypoints/llm/test_generate.py --ignore=entrypoints/llm/test_collective_rpc.py --ignore=entrypoints/llm/offline_mode
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/llm/test_generate.py # it needs a clean process
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/llm/offline_mode # Needs to avoid interference with other tests
   mirror:
     amd:
       device: mi325_1
@@ -41,9 +40,8 @@ steps:
   - vllm/
   - tests/entrypoints/serve
   commands:
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - pytest -v -s entrypoints/serve --ignore=entrypoints/serve/dev/rpc
-  - PYTHONPATH=/vllm-workspace pytest -v -s entrypoints/serve/dev/rpc
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/serve --ignore=entrypoints/serve/dev/rpc
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn PYTHONPATH=/vllm-workspace pytest -v -s entrypoints/serve/dev/rpc
   mirror:
     amd:
       device: mi325_1
@@ -59,8 +57,7 @@ steps:
   - tests/entrypoints/openai
   - tests/entrypoints/test_chat_utils
   commands:
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - pytest -v -s entrypoints/openai --ignore=entrypoints/openai/completion --ignore=entrypoints/openai/chat_completion --ignore=entrypoints/openai/responses --ignore=entrypoints/openai/correctness
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/openai --ignore=entrypoints/openai/completion --ignore=entrypoints/openai/chat_completion --ignore=entrypoints/openai/responses --ignore=entrypoints/openai/correctness
   mirror:
     amd:
       device: mi325_1
@@ -77,9 +74,8 @@ steps:
   - tests/entrypoints/openai
   - tests/entrypoints/test_chat_utils
   commands:
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - pytest -v -s entrypoints/openai/chat_completion
-  - pytest -v -s entrypoints/openai/completion --ignore=entrypoints/openai/completion/test_tensorizer_entrypoint.py
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/openai/chat_completion
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/openai/completion --ignore=entrypoints/openai/completion/test_tensorizer_entrypoint.py
   mirror:
     amd:
       device: mi325_1
@@ -128,8 +124,7 @@ steps:
   - vllm/
   - tests/entrypoints/speech_to_text
   commands:
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - pytest -v -s entrypoints/speech_to_text
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/speech_to_text
 
 - label: Entrypoints Integration (Multimodal)
   device: h200_35gb
@@ -140,8 +135,7 @@ steps:
   - vllm/
   - tests/entrypoints/multimodal
   commands:
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - pytest -v -s entrypoints/multimodal
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/multimodal
 
 - label: Entrypoints Integration (Pooling)
   key: entrypoints-integration-pooling
@@ -151,8 +145,7 @@ steps:
   - vllm/
   - tests/entrypoints/pooling
   commands:
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - pytest -v -s entrypoints/pooling
+  - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/pooling
 
 - label: OpenAI API Correctness
   key: openai-api-correctness
diff --git a/.buildkite/test_areas/lm_eval.yaml b/.buildkite/test_areas/lm_eval.yaml
index a5beb5ea36c..594b3d73c9e 100644
--- a/.buildkite/test_areas/lm_eval.yaml
+++ b/.buildkite/test_areas/lm_eval.yaml
@@ -50,8 +50,7 @@ steps:
   - csrc/
   - vllm/model_executor/layers/quantization
   commands:
-    - export VLLM_USE_DEEP_GEMM=0  # We found Triton is faster than DeepGEMM for H100
-    - pytest -s -v test_lm_eval_correctness.py --config-list-file=configs/models-large-hopper.txt --tp-size=4
+    - VLLM_USE_DEEP_GEMM=0 pytest -s -v test_lm_eval_correctness.py --config-list-file=configs/models-large-hopper.txt --tp-size=4  # Triton is faster than DeepGEMM for H100
 
 - label: LM Eval Small Models (B200)
   key: lm-eval-small-models-b200
@@ -108,9 +107,7 @@ steps:
       depends_on:
       - image-build-amd
       commands:
-      - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-      - export PYTORCH_ROCM_ARCH=gfx942 # Limit Quark compilation to save time
-      - pytest -s -v evals/gsm8k/test_gsm8k_correctness.py --config-list-file=configs/models-mi3xx.txt
+      - VLLM_WORKER_MULTIPROC_METHOD=spawn PYTORCH_ROCM_ARCH=gfx942 pytest -s -v evals/gsm8k/test_gsm8k_correctness.py --config-list-file=configs/models-mi3xx.txt  # Limit Quark compilation to save time
 
 - label: MoE Refactor Integration Test (H100 - TEMPORARY)
   key: moe-refactor-integration-test-h100-temporary
diff --git a/.buildkite/test_areas/lora.yaml b/.buildkite/test_areas/lora.yaml
index bd437c52265..6ccb7566c58 100644
--- a/.buildkite/test_areas/lora.yaml
+++ b/.buildkite/test_areas/lora.yaml
@@ -36,14 +36,14 @@ steps:
   commands:
     # FIXIT: find out which code initialize cuda before running the test
     # before the fix, we need to use spawn to test it
-    - export VLLM_WORKER_MULTIPROC_METHOD=spawn
+    #
     # Alot of these tests are on the edge of OOMing
-    - export PYTORCH_CUDA_ALLOC_CONF=expandable_segments:True
+    #
     # There is some Tensor Parallelism related processing logic in LoRA that
     # requires multi-GPU testing for validation.
-    - pytest -v -s -x lora/test_chatglm3_tp.py
-    - pytest -v -s -x lora/test_llama_tp.py
-    - pytest -v -s -x lora/test_qwen3_with_multi_loras.py
-    - pytest -v -s -x lora/test_olmoe_tp.py
-    - pytest -v -s -x lora/test_gptoss_tp.py
-    - pytest -v -s -x lora/test_qwen35_densemodel_lora.py
\ No newline at end of file
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn PYTORCH_CUDA_ALLOC_CONF=expandable_segments:True pytest -v -s -x lora/test_chatglm3_tp.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn PYTORCH_CUDA_ALLOC_CONF=expandable_segments:True pytest -v -s -x lora/test_llama_tp.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn PYTORCH_CUDA_ALLOC_CONF=expandable_segments:True pytest -v -s -x lora/test_qwen3_with_multi_loras.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn PYTORCH_CUDA_ALLOC_CONF=expandable_segments:True pytest -v -s -x lora/test_olmoe_tp.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn PYTORCH_CUDA_ALLOC_CONF=expandable_segments:True pytest -v -s -x lora/test_gptoss_tp.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn PYTORCH_CUDA_ALLOC_CONF=expandable_segments:True pytest -v -s -x lora/test_qwen35_densemodel_lora.py
\ No newline at end of file
diff --git a/.buildkite/test_areas/misc.yaml b/.buildkite/test_areas/misc.yaml
index 5c98006049f..5f429ff7019 100644
--- a/.buildkite/test_areas/misc.yaml
+++ b/.buildkite/test_areas/misc.yaml
@@ -18,9 +18,8 @@ steps:
     - vllm/v1/
     - tests/v1/spec_decode
   commands:
-    - export VLLM_WORKER_MULTIPROC_METHOD=spawn
     # TODO: create another `optional` test group for slow tests
-    - pytest -v -s -m 'not slow_test' v1/spec_decode
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s -m 'not slow_test' v1/spec_decode
   mirror:
     amd:
       device: mi300_1
@@ -50,12 +49,11 @@ steps:
     - tests/v1/test_request.py
     - tests/v1/test_outputs.py
   commands:
-    - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-    - pytest -v -s v1/sample
-    - pytest -v -s v1/logits_processors
-    - pytest -v -s v1/test_oracle.py
-    - pytest -v -s v1/test_request.py
-    - pytest -v -s v1/test_outputs.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/sample
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/logits_processors
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/test_oracle.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/test_request.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/test_outputs.py
   mirror:
     amd:
       device: mi325_1
@@ -93,18 +91,17 @@ steps:
     - tests/entrypoints/openai/correctness/test_lmeval.py
   commands:
     - bash /vllm-workspace/.buildkite/scripts/install-kv-connectors.sh
-    - export VLLM_WORKER_MULTIPROC_METHOD=spawn
     # split the test to avoid interference
-    - pytest -v -s -m 'not cpu_test' v1/core
-    - pytest -v -s v1/executor
-    - pytest -v -s v1/kv_offload
-    - pytest -v -s v1/simple_kv_offload
-    - pytest -v -s v1/worker
-    - pytest -v -s -m 'not cpu_test' v1/kv_connector/unit
-    - pytest -v -s -m 'not cpu_test' v1/metrics
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s -m 'not cpu_test' v1/core
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/executor
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/kv_offload
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/simple_kv_offload
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/worker
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s -m 'not cpu_test' v1/kv_connector/unit
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s -m 'not cpu_test' v1/metrics
     # Integration test for streaming correctness (requires special branch).
     - pip install -U git+https://github.com/robertgshaw2-redhat/lm-evaluation-harness.git@streaming-api
-    - pytest -v -s entrypoints/openai/correctness/test_lmeval.py::test_lm_eval_accuracy_v1_engine
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/openai/correctness/test_lmeval.py::test_lm_eval_accuracy_v1_engine
   mirror:
     amd:
       device: mi325_1
@@ -153,8 +150,7 @@ steps:
     - vllm/distributed/kv_transfer/kv_connector/v1/example_hidden_states_connector.py
     - tests/v1/kv_connector/extract_hidden_states_integration
   commands:
-    - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-    - pytest -v -s v1/kv_connector/extract_hidden_states_integration
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/kv_connector/extract_hidden_states_integration
 
 - label: Extract Hidden States Integration (2 GPUs)
   key: extract-hidden-states-integration-2-gpus
@@ -167,8 +163,7 @@ steps:
     - vllm/distributed/kv_transfer/kv_connector/v1/example_hidden_states_connector.py
     - tests/v1/kv_connector/extract_hidden_states_integration
   commands:
-    - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-    - pytest -v -s -m 'distributed' v1/kv_connector/extract_hidden_states_integration
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s -m 'distributed' v1/kv_connector/extract_hidden_states_integration
 
 - label: Regression
   key: regression
@@ -360,10 +355,9 @@ steps:
     - vllm/model_executor/layers
     - tests/v1/determinism/
   commands:
-    - export VLLM_WORKER_MULTIPROC_METHOD=spawn
     - pip install pytest-timeout pytest-forked
-    - pytest -v -s v1/determinism/test_batch_invariance.py
-    - VLLM_TEST_MODEL=deepseek-ai/DeepSeek-V2-Lite-Chat pytest -v -s v1/determinism/test_batch_invariance.py::test_v1_generation_is_deterministic_across_batch_sizes_with_needle[TRITON_MLA]
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/determinism/test_batch_invariance.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn VLLM_TEST_MODEL=deepseek-ai/DeepSeek-V2-Lite-Chat pytest -v -s v1/determinism/test_batch_invariance.py::test_v1_generation_is_deterministic_across_batch_sizes_with_needle[TRITON_MLA]
 
 - label: Batch Invariance (H100)
   key: batch-invariance-h100
@@ -374,12 +368,11 @@ steps:
     - vllm/model_executor/layers
     - tests/v1/determinism/
   commands:
-    - export VLLM_WORKER_MULTIPROC_METHOD=spawn
     - pip install pytest-timeout pytest-forked
-    - pytest -v -s v1/determinism/test_batch_invariance.py
-    - pytest -v -s v1/determinism/test_rms_norm_batch_invariant.py
-    - VLLM_TEST_MODEL=deepseek-ai/DeepSeek-V2-Lite-Chat pytest -v -s v1/determinism/test_batch_invariance.py::test_v1_generation_is_deterministic_across_batch_sizes_with_needle[TRITON_MLA]
-    - VLLM_TEST_MODEL=Qwen/Qwen3-30B-A3B-Thinking-2507-FP8 pytest -v -s v1/determinism/test_batch_invariance.py::test_v1_generation_is_deterministic_across_batch_sizes_with_needle[FLASH_ATTN]
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/determinism/test_batch_invariance.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/determinism/test_rms_norm_batch_invariant.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn VLLM_TEST_MODEL=deepseek-ai/DeepSeek-V2-Lite-Chat pytest -v -s v1/determinism/test_batch_invariance.py::test_v1_generation_is_deterministic_across_batch_sizes_with_needle[TRITON_MLA]
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn VLLM_TEST_MODEL=Qwen/Qwen3-30B-A3B-Thinking-2507-FP8 pytest -v -s v1/determinism/test_batch_invariance.py::test_v1_generation_is_deterministic_across_batch_sizes_with_needle[FLASH_ATTN]
 
 - label: Batch Invariance (B200)
   key: batch-invariance-b200
@@ -390,14 +383,13 @@ steps:
     - vllm/model_executor/layers
     - tests/v1/determinism/
   commands:
-    - export VLLM_WORKER_MULTIPROC_METHOD=spawn
     - pip install pytest-timeout pytest-forked
-    - pytest -v -s v1/determinism/test_batch_invariance.py
-    - pytest -v -s v1/determinism/test_rms_norm_batch_invariant.py
-    - VLLM_TEST_MODEL=deepseek-ai/DeepSeek-V2-Lite-Chat pytest -v -s v1/determinism/test_batch_invariance.py::test_v1_generation_is_deterministic_across_batch_sizes_with_needle[TRITON_MLA]
-    - VLLM_TEST_MODEL=Qwen/Qwen3-30B-A3B-Thinking-2507-FP8 pytest -v -s v1/determinism/test_batch_invariance.py::test_v1_generation_is_deterministic_across_batch_sizes_with_needle[FLASH_ATTN]
-    - pytest -v -s v1/determinism/test_nvfp4_batch_invariant.py
-    - pytest -v -s v1/determinism/test_nvfp4_batch_invariant_scaled_mm.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/determinism/test_batch_invariance.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/determinism/test_rms_norm_batch_invariant.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn VLLM_TEST_MODEL=deepseek-ai/DeepSeek-V2-Lite-Chat pytest -v -s v1/determinism/test_batch_invariance.py::test_v1_generation_is_deterministic_across_batch_sizes_with_needle[TRITON_MLA]
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn VLLM_TEST_MODEL=Qwen/Qwen3-30B-A3B-Thinking-2507-FP8 pytest -v -s v1/determinism/test_batch_invariance.py::test_v1_generation_is_deterministic_across_batch_sizes_with_needle[FLASH_ATTN]
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/determinism/test_nvfp4_batch_invariant.py
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/determinism/test_nvfp4_batch_invariant_scaled_mm.py
   
 - label: Acceptance Length Test (Large Models) # optional
   device: h200_35gb
@@ -412,5 +404,4 @@ steps:
   - vllm/model_executor/models/mlp_speculator.py
   - tests/v1/spec_decode/test_acceptance_length.py
   commands:
-    - export VLLM_ALLOW_INSECURE_SERIALIZATION=1
-    - pytest -v -s v1/spec_decode/test_acceptance_length.py -m slow_test
+    - VLLM_ALLOW_INSECURE_SERIALIZATION=1 pytest -v -s v1/spec_decode/test_acceptance_length.py -m slow_test
diff --git a/.buildkite/test_areas/model_executor.yaml b/.buildkite/test_areas/model_executor.yaml
index e34b7eadfac..df9c6818a97 100644
--- a/.buildkite/test_areas/model_executor.yaml
+++ b/.buildkite/test_areas/model_executor.yaml
@@ -13,13 +13,12 @@ steps:
   - tests/entrypoints/openai/completion/test_tensorizer_entrypoint.py
   commands:
     - apt-get update && apt-get install -y curl libsodium23
-    - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-    # Dump tracebacks of all threads if a test hangs, so a wedged GPU/CUDA
-    # init surfaces a stack instead of silently stalling.
-    - export PYTHONFAULTHANDLER=1
     # Per-test watchdog: a single hung test (e.g. stuck during engine/CUDA
     # init) fails fast with a traceback instead of running until the global
     # build timeout. The `thread` method also handles hangs inside C/CUDA
     # calls that the signal method cannot interrupt.
-    - pytest -v -s model_executor -m '(not slow_test)' --timeout=900 --timeout-method=thread
-    - pytest -v -s entrypoints/openai/completion/test_tensorizer_entrypoint.py --timeout=900 --timeout-method=thread
+    #
+    # Env vars are inlined because CONTINUE_ON_FAILURE wraps each command
+    # in a subshell, so a standalone `export` would be lost.
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn PYTHONFAULTHANDLER=1 pytest -v -s model_executor -m '(not slow_test)' --timeout=900 --timeout-method=thread
+    - VLLM_WORKER_MULTIPROC_METHOD=spawn PYTHONFAULTHANDLER=1 pytest -v -s entrypoints/openai/completion/test_tensorizer_entrypoint.py --timeout=900 --timeout-method=thread
diff --git a/.buildkite/test_areas/model_runner_v2.yaml b/.buildkite/test_areas/model_runner_v2.yaml
index 617c80b2fec..7170d0ab1cf 100644
--- a/.buildkite/test_areas/model_runner_v2.yaml
+++ b/.buildkite/test_areas/model_runner_v2.yaml
@@ -16,15 +16,14 @@ steps:
   - tests/entrypoints/llm/test_struct_output_generate.py
   commands:
   - set -x
-  - export VLLM_USE_V2_MODEL_RUNNER=1
-  - pytest -v -s v1/engine/test_llm_engine.py -k "not test_engine_metrics"
+  - VLLM_USE_V2_MODEL_RUNNER=1 pytest -v -s v1/engine/test_llm_engine.py -k "not test_engine_metrics"
   # This requires eager until we sort out CG correctness issues.
   # TODO: remove ENFORCE_EAGER here after https://github.com/vllm-project/vllm/pull/32936 is merged.
-  - ENFORCE_EAGER=1 pytest -v -s v1/e2e/general/test_async_scheduling.py -k "not ngram"
-  - pytest -v -s v1/e2e/general/test_context_length.py
-  - pytest -v -s v1/e2e/general/test_min_tokens.py
+  - VLLM_USE_V2_MODEL_RUNNER=1 ENFORCE_EAGER=1 pytest -v -s v1/e2e/general/test_async_scheduling.py -k "not ngram"
+  - VLLM_USE_V2_MODEL_RUNNER=1 pytest -v -s v1/e2e/general/test_context_length.py
+  - VLLM_USE_V2_MODEL_RUNNER=1 pytest -v -s v1/e2e/general/test_min_tokens.py
   # Temporary hack filter to exclude ngram spec decoding based tests.
-  - pytest -v -s entrypoints/llm/test_struct_output_generate.py -k "xgrammar and not speculative_config6 and not speculative_config7 and not speculative_config8 and not speculative_config0"
+  - VLLM_USE_V2_MODEL_RUNNER=1 pytest -v -s entrypoints/llm/test_struct_output_generate.py -k "xgrammar and not speculative_config6 and not speculative_config7 and not speculative_config8 and not speculative_config0"
 
 - label: Model Runner V2 Examples
   device: h200_35gb
@@ -42,26 +41,25 @@ steps:
     - examples/features/tensorize_vllm_model.py
   commands:
     - set -x
-    - export VLLM_USE_V2_MODEL_RUNNER=1
     - pip install tensorizer # for tensorizer test
-    - python3 basic/offline_inference/chat.py # for basic
-    - python3 basic/offline_inference/generate.py --model facebook/opt-125m
-    #- python3 basic/offline_inference/generate.py --model meta-llama/Llama-2-13b-chat-hf --cpu-offload-gb 10  # TODO
-    #- python3 basic/offline_inference/embed.py   # TODO
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 basic/offline_inference/chat.py # for basic
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 basic/offline_inference/generate.py --model facebook/opt-125m
+    #- VLLM_USE_V2_MODEL_RUNNER=1 python3 basic/offline_inference/generate.py --model meta-llama/Llama-2-13b-chat-hf --cpu-offload-gb 10  # TODO
+    #- VLLM_USE_V2_MODEL_RUNNER=1 python3 basic/offline_inference/embed.py   # TODO
     # for multi-modal models
-    - python3 generate/multimodal/audio_language_offline.py --seed 0
-    - python3 generate/multimodal/vision_language_offline.py --seed 0
-    - python3 generate/multimodal/vision_language_multi_image_offline.py --seed 0
-    - python3 generate/multimodal/encoder_decoder_multimodal_offline.py --model-type whisper --seed 0
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 generate/multimodal/audio_language_offline.py --seed 0
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 generate/multimodal/vision_language_offline.py --seed 0
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 generate/multimodal/vision_language_multi_image_offline.py --seed 0
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 generate/multimodal/encoder_decoder_multimodal_offline.py --model-type whisper --seed 0
     # for pooling models
-    - python3 pooling/embed/vision_embedding_offline.py --seed 0
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 pooling/embed/vision_embedding_offline.py --seed 0
     # for features demo
-    - python3 features/automatic_prefix_caching/prefix_caching_offline.py
-    - python3 deployment/llm_engine_example.py
-    - python3 features/tensorize_vllm_model.py --model facebook/opt-125m serialize --serialized-directory /tmp/ --suffix v1 && python3 features/tensorize_vllm_model.py --model facebook/opt-125m deserialize --path-to-tensors /tmp/vllm/facebook/opt-125m/v1/model.tensors
-    - python3 features/speculative_decoding/spec_decode_offline.py --test --method eagle --num_spec_tokens 3 --dataset-name hf --dataset-path philschmid/mt-bench --num-prompts 80 --temp 0 --top-p 1.0 --top-k -1 --tp 1 --enable-chunked-prefill --max-model-len 2048
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 features/automatic_prefix_caching/prefix_caching_offline.py
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 deployment/llm_engine_example.py
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 features/tensorize_vllm_model.py --model facebook/opt-125m serialize --serialized-directory /tmp/ --suffix v1 && VLLM_USE_V2_MODEL_RUNNER=1 python3 features/tensorize_vllm_model.py --model facebook/opt-125m deserialize --path-to-tensors /tmp/vllm/facebook/opt-125m/v1/model.tensors
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 features/speculative_decoding/spec_decode_offline.py --test --method eagle --num_spec_tokens 3 --dataset-name hf --dataset-path philschmid/mt-bench --num-prompts 80 --temp 0 --top-p 1.0 --top-k -1 --tp 1 --enable-chunked-prefill --max-model-len 2048
     # https://github.com/vllm-project/vllm/pull/26682 uses slightly more memory in PyTorch 2.9+ causing this test to OOM in 1xL4 GPU
-    - python3 features/speculative_decoding/spec_decode_offline.py --test --method eagle3 --num_spec_tokens 3 --dataset-name hf --dataset-path philschmid/mt-bench --num-prompts 80 --temp 0 --top-p 1.0 --top-k -1 --tp 1 --enable-chunked-prefill --max-model-len 1536
+    - VLLM_USE_V2_MODEL_RUNNER=1 python3 features/speculative_decoding/spec_decode_offline.py --test --method eagle3 --num_spec_tokens 3 --dataset-name hf --dataset-path philschmid/mt-bench --num-prompts 80 --temp 0 --top-p 1.0 --top-k -1 --tp 1 --enable-chunked-prefill --max-model-len 1536
 
 - label: Model Runner V2 Distributed (2 GPUs)
   key: model-runner-v2-distributed-2-gpus
@@ -76,13 +74,11 @@ steps:
     - tests/v1/distributed/test_eagle_dp.py
   commands:
     - set -x
-    - export VLLM_USE_V2_MODEL_RUNNER=1
     # The "and not True" here is a hacky way to exclude the prompt_embeds cases which aren't yet supported.
-    - TARGET_TEST_SUITE=L4 pytest -v -s basic_correctness/test_basic_correctness.py -m 'distributed(num_gpus=2)' -k "not ray and not True"
+    - VLLM_USE_V2_MODEL_RUNNER=1 TARGET_TEST_SUITE=L4 pytest -v -s basic_correctness/test_basic_correctness.py -m 'distributed(num_gpus=2)' -k "not ray and not True"
     # https://github.com/NVIDIA/nccl/issues/1838
-    - export NCCL_CUMEM_HOST_ENABLE=0
-    - TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_async_llm_dp.py -k "not ray"
-    - TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_eagle_dp.py
+    - VLLM_USE_V2_MODEL_RUNNER=1 NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_async_llm_dp.py -k "not ray"
+    - VLLM_USE_V2_MODEL_RUNNER=1 NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_eagle_dp.py
 
 - label: Model Runner V2 Pipeline Parallelism (4 GPUs)
   key: model-runner-v2-pipeline-parallelism-4-gpus
@@ -97,10 +93,9 @@ steps:
     - tests/v1/distributed/test_pp_dp_v2.py
   commands:
     - set -x
-    - export VLLM_USE_V2_MODEL_RUNNER=1
-    - pytest -v -s distributed/test_pipeline_parallel.py -k "not ray and not Jamba"
-    - pytest -v -s distributed/test_pp_cudagraph.py -k "not ray"
-    - pytest -v -s v1/distributed/test_pp_dp_v2.py
+    - VLLM_USE_V2_MODEL_RUNNER=1 pytest -v -s distributed/test_pipeline_parallel.py -k "not ray and not Jamba"
+    - VLLM_USE_V2_MODEL_RUNNER=1 pytest -v -s distributed/test_pp_cudagraph.py -k "not ray"
+    - VLLM_USE_V2_MODEL_RUNNER=1 pytest -v -s v1/distributed/test_pp_dp_v2.py
 
 - label: Model Runner V2 Spec Decode
   device: h200_35gb
@@ -115,8 +110,7 @@ steps:
   - tests/v1/e2e/spec_decode/test_spec_decode.py
   commands:
   - set -x
-  - export VLLM_USE_V2_MODEL_RUNNER=1
-  - pytest -v -s v1/spec_decode/test_max_len.py -k "eagle or mtp"
-  - pytest -v -s v1/spec_decode/test_rejection_sampler_utils.py
-  - pytest -v -s v1/spec_decode/test_synthetic_rejection_sampler_utils.py
-  - pytest -v -s v1/e2e/spec_decode/test_spec_decode.py -k "eagle or mtp"
+  - VLLM_USE_V2_MODEL_RUNNER=1 pytest -v -s v1/spec_decode/test_max_len.py -k "eagle or mtp"
+  - VLLM_USE_V2_MODEL_RUNNER=1 pytest -v -s v1/spec_decode/test_rejection_sampler_utils.py
+  - VLLM_USE_V2_MODEL_RUNNER=1 pytest -v -s v1/spec_decode/test_synthetic_rejection_sampler_utils.py
+  - VLLM_USE_V2_MODEL_RUNNER=1 pytest -v -s v1/e2e/spec_decode/test_spec_decode.py -k "eagle or mtp"
diff --git a/.buildkite/test_areas/rust_frontend.yaml b/.buildkite/test_areas/rust_frontend.yaml
index f9abac2004e..dedd18d7a25 100644
--- a/.buildkite/test_areas/rust_frontend.yaml
+++ b/.buildkite/test_areas/rust_frontend.yaml
@@ -23,17 +23,15 @@ steps:
   # - tests/entrypoints/openai/test_uds.py
   - tests/v1/sample/test_logprobs_e2e.py
   commands:
-  - export VLLM_USE_RUST_FRONTEND=1
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - pytest -v -s benchmarks/test_serve_cli.py -k "not insecure and not (test_bench_serve and not test_bench_serve_chat)"
-  - pytest -v -s entrypoints/openai/chat_completion/test_chat_completion.py
-  # - pytest -v -s entrypoints/openai/chat_completion/test_chat_logit_bias_validation.py -k "not invalid"
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s benchmarks/test_serve_cli.py -k "not insecure and not (test_bench_serve and not test_bench_serve_chat)"
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/openai/chat_completion/test_chat_completion.py
+  # - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/openai/chat_completion/test_chat_logit_bias_validation.py -k "not invalid"
 
-  # - pytest -v -s entrypoints/openai/completion/test_prompt_validation.py -k "not prompt_embeds"
-  - pytest -v -s entrypoints/openai/completion/test_shutdown.py -k "not engine_failure and not test_abort_timeout_exits_quickly"
-  # - pytest -v -s entrypoints/openai/test_return_token_ids.py
-  # - pytest -v -s entrypoints/openai/test_uds.py
-  - pytest -v -s v1/sample/test_logprobs_e2e.py -k "test_prompt_logprobs_e2e_server"
+  # - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/openai/completion/test_prompt_validation.py -k "not prompt_embeds"
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/openai/completion/test_shutdown.py -k "not engine_failure and not test_abort_timeout_exits_quickly"
+  # - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/openai/test_return_token_ids.py
+  # - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/openai/test_uds.py
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s v1/sample/test_logprobs_e2e.py -k "test_prompt_logprobs_e2e_server"
 
 - label: Rust Frontend Serve/Admin Coverage
   timeout_in_minutes: 60
@@ -51,13 +49,11 @@ steps:
   - tests/entrypoints/serve/instrumentator/test_metrics.py
   # - tests/entrypoints/serve/dev/test_sleep.py
   commands:
-  - export VLLM_USE_RUST_FRONTEND=1
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  # - pytest -v -s entrypoints/serve/dev/rpc/test_collective_rpc.py
-  - pytest -v -s entrypoints/serve/instrumentator/test_basic.py -k "not show_version and not server_load"
-  - pytest -v -s entrypoints/serve/disagg/test_serving_tokens.py -k "not stream and not lora and not test_generate_logprobs and not stop_string_workflow"
-  - pytest -v -s entrypoints/serve/instrumentator/test_metrics.py -k "text and not show and not run_batch and not test_metrics_counts and not test_metrics_exist"
-  # - pytest -v -s entrypoints/serve/dev/test_sleep.py
+  # - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/serve/dev/rpc/test_collective_rpc.py
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/serve/instrumentator/test_basic.py -k "not show_version and not server_load"
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/serve/disagg/test_serving_tokens.py -k "not stream and not lora and not test_generate_logprobs and not stop_string_workflow"
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/serve/instrumentator/test_metrics.py -k "text and not show and not run_batch and not test_metrics_counts and not test_metrics_exist"
+  # - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s entrypoints/serve/dev/test_sleep.py
 
 - label: Rust Frontend Core Correctness
   timeout_in_minutes: 30
@@ -69,9 +65,7 @@ steps:
   - tests/utils.py
   - tests/entrypoints/openai/correctness/test_lmeval.py
   commands:
-  - export VLLM_USE_RUST_FRONTEND=1
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - pytest -s entrypoints/openai/correctness/test_lmeval.py::test_lm_eval_accuracy_v1_engine
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -s entrypoints/openai/correctness/test_lmeval.py::test_lm_eval_accuracy_v1_engine
 
 - label: Rust Frontend Tool Use
   timeout_in_minutes: 60
@@ -83,9 +77,7 @@ steps:
   - tests/utils.py
   - tests/tool_use/
   commands:
-  - export VLLM_USE_RUST_FRONTEND=1
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - pytest -v -s tool_use --ignore=tool_use/mistral --models llama3.2 -k "not test_response_format_with_tool_choice_required and not test_parallel_tool_calls_false and not test_tool_call_and_choice"
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn pytest -v -s tool_use --ignore=tool_use/mistral --models llama3.2 -k "not test_response_format_with_tool_choice_required and not test_parallel_tool_calls_false and not test_tool_call_and_choice"
 
 - label: Rust Frontend Distributed
   timeout_in_minutes: 30
@@ -103,9 +95,6 @@ steps:
   - tests/v1/distributed/test_hybrid_lb_dp.py
   - tests/v1/distributed/test_internal_lb_dp.py
   commands:
-  - export VLLM_USE_RUST_FRONTEND=1
-  - export VLLM_WORKER_MULTIPROC_METHOD=spawn
-  - export NCCL_CUMEM_HOST_ENABLE=0
-  - TP_SIZE=1 DP_SIZE=4 pytest -v -s v1/distributed/test_internal_lb_dp.py -k "not 4 and not server_info"
-  - TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_external_lb_dp.py -k "not 4 and not server_info"
-  - TP_SIZE=1 DP_SIZE=4 pytest -v -s v1/distributed/test_hybrid_lb_dp.py -k "not 4 and not server_info"
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=1 DP_SIZE=4 pytest -v -s v1/distributed/test_internal_lb_dp.py -k "not 4 and not server_info"
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=1 DP_SIZE=2 pytest -v -s v1/distributed/test_external_lb_dp.py -k "not 4 and not server_info"
+  - VLLM_USE_RUST_FRONTEND=1 VLLM_WORKER_MULTIPROC_METHOD=spawn NCCL_CUMEM_HOST_ENABLE=0 TP_SIZE=1 DP_SIZE=4 pytest -v -s v1/distributed/test_hybrid_lb_dp.py -k "not 4 and not server_info"
diff --git a/.buildkite/test_areas/spec_decode.yaml b/.buildkite/test_areas/spec_decode.yaml
index 6e532eddc71..0f0fb3ce3d2 100644
--- a/.buildkite/test_areas/spec_decode.yaml
+++ b/.buildkite/test_areas/spec_decode.yaml
@@ -153,8 +153,7 @@ steps:
     - vllm/model_executor/models/qwen3_dflash.py
     - tests/v1/spec_decode/test_speculators_correctness.py
   commands:
-    - export VLLM_ALLOW_INSECURE_SERIALIZATION=1
-    - pytest -v -s v1/spec_decode/test_speculators_correctness.py -m slow_test
+    - VLLM_ALLOW_INSECURE_SERIALIZATION=1 pytest -v -s v1/spec_decode/test_speculators_correctness.py -m slow_test
 
 - label: Spec Decode MTP hybrid (B200)
   timeout_in_minutes: 30