diff --git a/src/levanter/infra/ray_tpu.py b/src/levanter/infra/ray_tpu.py
index 57f484770..c53d42f82 100644
--- a/src/levanter/infra/ray_tpu.py
+++ b/src/levanter/infra/ray_tpu.py
@@ -11,6 +11,7 @@
 from typing import Callable, Optional, Sequence
 
 import draccus
+import mergedeep
 import ray
 from ray._private.accelerators import TPUAcceleratorManager
 from ray.dashboard.modules.job.sdk import JobSubmissionClient
@@ -198,10 +199,15 @@ def _redecorate_remote_fn_for_tpu(remote_fn, num_hosts, **runtime_env):
     tpu_name = ray.util.accelerators.tpu.get_current_pod_name()  # -> my-tpu
     num_tpus_per_host = TPUAcceleratorManager.get_current_node_num_accelerators()  # -> 8
 
+    # ray doesn't merge the runtime envs properly, so we have to do it ourselves
+    # we need to do a deep merge
+    runtime_env = mergedeep.merge({}, runtime_env, remote_fn._runtime_env, strategy=mergedeep.Strategy.ADDITIVE)
+
     remote_fn = remote_fn.options(
         runtime_env=runtime_env,
         resources={tpu_name: 1, "TPU": num_tpus_per_host},
     )
+
     logger.info(f"Running on TPU {tpu_name} with {num_hosts} hosts and {num_tpus_per_host} TPUs per host")
     return remote_fn, tpu_name
 
@@ -583,6 +589,16 @@ def _make_unique_job_id(client, run_id):
     return job_id
 
 
+def _deep_merge_envs(env1, env2):
+    """
+    Merge two environment dictionaries, deeply.
+    """
+
+    merged = mergedeep.merge({}, env1, env2, strategy=mergedeep.Strategy.ADDITIVE)
+
+    return merged
+
+
 @draccus.wrap()
 def main(args: RunDockerOnPodConfig):
     """