diff --git a/hancho.py b/hancho.py
index b0cbcf7..61bb082 100755
--- a/hancho.py
+++ b/hancho.py
@@ -15,6 +15,7 @@
 import traceback
 import types
 from pathlib import Path
+from os.path import abspath, relpath
 
 # If we were launched directly, a reference to this module is already in
 # sys.modules[__name__]. Stash another reference in sys.modules["hancho"] so
@@ -179,6 +180,8 @@ def main():
 
     this.config.filename = Path(this.config.filename)
 
+    this.config.hancho_root = Path.cwd()
+
     # Unrecognized flags become global config fields.
     for span in unrecognized:
         if match := re.match(r"-+([^=\s]+)(?:=(\S+))?", span):
@@ -522,9 +525,11 @@ async def dispatch(self):
 
         # Check for duplicate task outputs
         for file in self.abs_files_out:
-            if file in this.hancho_outs:
-                raise NameError(f"Multiple rules build {file}!")
-            this.hancho_outs.add(file)
+            res_file = file.resolve()
+            if res_file in this.hancho_outs:
+                rel_file = relpath(res_file, this.config.hancho_root)
+                raise NameError(f"Multiple rules build {rel_file}!")
+            this.hancho_outs.add(res_file)
 
         # Check if we need a rebuild
         self.reason = await self.needs_rerun()
@@ -578,6 +583,8 @@ async def dispatch(self):
         return result
 
     ########################################
+    # Note - We should _not_ be expanding any templates in this step, that
+    # should've been done already.
 
     async def run_command(self, command):
         """Actually runs a command, either by calling it or running it in a subprocess"""
@@ -600,11 +607,14 @@ async def run_command(self, command):
             raise ValueError(f"Don't know what to do with {command}")
 
         # Create the subprocess via asyncio and then await the result.
+        old_dir = os.getcwd()
+        if self.task_dir: os.chdir(self.task_dir)
         proc = await asyncio.create_subprocess_shell(
             command,
             stdout=asyncio.subprocess.PIPE,
             stderr=asyncio.subprocess.PIPE,
         )
+        os.chdir(old_dir)
         (stdout_data, stderr_data) = await proc.communicate()
 
         self.stdout = stdout_data.decode()
diff --git a/tests/test.py b/tests/test.py
index 4f785ff..4403e3d 100755
--- a/tests/test.py
+++ b/tests/test.py
@@ -90,6 +90,10 @@ def test_garbage_command(self):
         """Non-existent command line commands should cause Hancho to fail the build."""
         self.assertNotEqual(0, run_hancho("garbage_command"))
 
+    def test_rule_collision(self):
+        """If multiple rules generate the same output file, that's an error."""
+        self.assertNotEqual(0, run_hancho("rule_collision"))
+
     def test_always_rebuild_if_no_inputs(self):
         """A rule with no inputs should always rebuild"""
         run_hancho("always_rebuild_if_no_inputs")