diff --git a/synthesize/config.py b/synthesize/config.py
index f30354a..04b36b4 100644
--- a/synthesize/config.py
+++ b/synthesize/config.py
@@ -55,7 +55,7 @@ class Target(Model):
     args: Args = {}
     envs: Envs = {}
 
-    executable: str = "sh -u"
+    executable: str = "sh -eu"
 
     @field_validator("commands")
     @classmethod
diff --git a/synthesize/execution.py b/synthesize/execution.py
index 6e6373f..bc21fd3 100644
--- a/synthesize/execution.py
+++ b/synthesize/execution.py
@@ -102,18 +102,15 @@ def has_exited(self) -> bool:
         return self.exit_code is not None
 
     def _send_signal(self, signal: int) -> None:
-        os.killpg(os.getpgid(self.process.pid), signal)
-
-    def terminate(self) -> None:
         if self.has_exited:
             return None
 
+        os.killpg(os.getpgid(self.process.pid), signal)
+
+    def terminate(self) -> None:
         self._send_signal(SIGTERM)
 
     def kill(self) -> None:
-        if self.has_exited:
-            return None
-
         self._send_signal(SIGKILL)
 
     async def wait(self) -> Execution:
diff --git a/tests/test_config.py b/tests/test_config.py
index b294923..7fc1bf1 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -57,29 +57,29 @@ def test_target_commands_dedenting(raw: str, expected: str) -> None:
     ("target", "args", "expected"),
     (
         (
-            Target(commands=""),
+            Target(commands="", executable="sh"),
             Args(),
-            f"#!{shutil.which('sh')} -u\n",
+            f"#!{shutil.which('sh')}\n",
         ),
         (
-            Target(commands="echo 'hello'"),
+            Target(commands="echo 'hello'", executable="sh"),
             Args(),
-            f"#!{shutil.which('sh')} -u\n\necho 'hello'",
+            f"#!{shutil.which('sh')}\n\necho 'hello'",
         ),
         (
-            Target(commands="echo '{{foo}}'"),
+            Target(commands="echo '{{foo}}'", executable="sh"),
             Args({"foo": "bar"}),
-            f"#!{shutil.which('sh')} -u\n\necho 'bar'",
+            f"#!{shutil.which('sh')}\n\necho 'bar'",
         ),
         (  # unused values are ok
-            Target(commands="echo '{{foo}}'"),
+            Target(commands="echo '{{foo}}'", executable="sh"),
             Args({"foo": "bar", "baz": "qux"}),
-            f"#!{shutil.which('sh')} -u\n\necho 'bar'",
+            f"#!{shutil.which('sh')}\n\necho 'bar'",
         ),
         (
-            Target(commands="echo {{foo}} {{baz}}"),
+            Target(commands="echo {{foo}} {{baz}}", executable="sh"),
             Args({"foo": "bar", "baz": "qux"}),
-            f"#!{shutil.which('sh')} -u\n\necho bar qux",
+            f"#!{shutil.which('sh')}\n\necho bar qux",
         ),
         (
             Target(commands="echo", executable="bash"),
@@ -87,14 +87,14 @@ def test_target_commands_dedenting(raw: str, expected: str) -> None:
             f"#!{shutil.which('bash')}\n\necho",
         ),
         (
-            Target(commands="{{ 'yes' if choice else 'no' }}"),
+            Target(commands="{{ 'yes' if choice else 'no' }}", executable="sh"),
             Args({"choice": True}),
-            f"#!{shutil.which('sh')} -u\n\nyes",
+            f"#!{shutil.which('sh')}\n\nyes",
         ),
         (
-            Target(commands="{{ 'yes' if choice else 'no' }}"),
+            Target(commands="{{ 'yes' if choice else 'no' }}", executable="sh"),
             Args({"choice": False}),
-            f"#!{shutil.which('sh')} -u\n\nno",
+            f"#!{shutil.which('sh')}\n\nno",
         ),
     ),
 )