diff --git a/src/dvsim/job/deploy.py b/src/dvsim/job/deploy.py
index 71247b85..54cf84a5 100644
--- a/src/dvsim/job/deploy.py
+++ b/src/dvsim/job/deploy.py
@@ -98,8 +98,16 @@ def __init__(self, sim_cfg: "SimCfg") -> None:
         # Do variable substitutions.
         self._subst_vars()
 
-        # List of vars required to be exported to sub-shell, as a dict.
-        self.exports = self._process_exports()
+        # List of vars required to be exported to sub-shell, as a dict. This
+        # has been loaded from the hjson as a list of dicts and we want to
+        # flatten it to a single dictionary.
+        #
+        # The slightly odd dance with the variables is to convince Pyright
+        # about the types we end up with.
+        exports_list: object = self.exports
+        if not isinstance(exports_list, list):
+            raise TypeError("Loaded exports value should be a list of dicts.")
+        self.exports: dict[str, str] = self._process_exports(exports_list)
 
         # Construct the job's command.
         self.cmd = self._construct_cmd()
@@ -276,7 +284,7 @@ def _subst_vars(self, ignored_subst_vars=None) -> None:
             ignore_error=False,
         )
 
-    def _process_exports(self) -> Mapping:
+    def _process_exports(self, exports_list: list[dict[str, str]]) -> dict[str, str]:
         """Convert 'exports' as a list of dicts in the HJson to a dict.
 
         Exports is a list of key-value pairs that are to be exported to the
@@ -286,7 +294,7 @@ def _process_exports(self) -> Mapping:
         into a dict variable, which makes it easy to merge the list of exports
         with the subprocess' env where the ASIC tool is invoked.
         """
-        return {k: str(v) for item in self.exports for k, v in item.items()}
+        return {k: str(v) for item in exports_list for k, v in item.items()}
 
     def _construct_cmd(self) -> str:
         """Construct the command that will eventually be launched."""