diff --git a/bou.py b/bou.py
index dae323f..d23471d 100755
--- a/bou.py
+++ b/bou.py
@@ -12,6 +12,10 @@ BUILD_FILES = ['build.yaml', 'build.yml', 'bou.yaml', 'bou.yml']
 ENV_VAR = re.compile(r'(\$([A-Za-z0-9_]+))')
 
 
+class StepFailedError(Exception):
+    pass
+
+
 def parse_args():
     """
     Parse command line arguments, and return an object with all the arguments
@@ -55,6 +59,7 @@ def setup_step(config, step_name):
     """
     step = config['steps'][step_name]
     step['environment'] = config.get('environment', []) + step.get('environment', [])
+    step['name'] = step_name
     return step
 
 
@@ -91,7 +96,9 @@ def run_step(step, base_path):
     for output in iter(lambda: proc.stdout.read(1), b''):
         sys.stdout.buffer.write(output)
         sys.stdout.buffer.flush()
-    return proc.returncode == 0
+    proc.stdout.close()
+    proc.wait()
+    return not proc.returncode
 
 
 def run_stage(config, stage_name, base_path):
@@ -102,10 +109,11 @@ def run_stage(config, stage_name, base_path):
     :param stage_name: The stage to run
     :param base_path: The base path of the build
     """
-    for step in get_steps_for_stage(config, stage_name):
+    steps = get_steps_for_stage(config, stage_name)
+    for step in steps:
         result = run_step(step, base_path)
         if not result:
-            break
+            raise StepFailedError('Error running step "{name}"'.format(name=step['name']))
 
 
 def get_all_stages(config):
@@ -161,24 +169,28 @@ def main():
     config = yaml.full_load(build_file.open())
     all_stages = get_all_stages(config)
     all_steps = get_all_steps(config)
-    if args.stage_or_step:
-        if args.stage_or_step in all_stages:
-            run_stage(config, args.stage_or_step, base_path)
-        elif args.stage_or_step in all_steps:
-            step = setup_step(config, args.stage_or_step)
-            run_step(config, step, base_path)
-        else:
-            print('"{stage}" is not a valid stage or step name'.format(stage=args.stage_or_step))
-            return 2
-    else:
-        stages = config.get('stages', all_stages)
-        if stages:
-            for stage_name in stages:
-                run_stage(config, stage_name, base_path)
-        else:
-            for step_name in all_steps:
-                step = setup_step(config, step_name)
+    try:
+        if args.stage_or_step:
+            if args.stage_or_step in all_stages:
+                run_stage(config, args.stage_or_step, base_path)
+            elif args.stage_or_step in all_steps:
+                step = setup_step(config, args.stage_or_step)
                 run_step(config, step, base_path)
+            else:
+                print('"{stage}" is not a valid stage or step name'.format(stage=args.stage_or_step))
+                return 2
+        else:
+            stages = config.get('stages', all_stages)
+            if stages:
+                for stage_name in stages:
+                    run_stage(config, stage_name, base_path)
+            else:
+                for step_name in all_steps:
+                    step = setup_step(config, step_name)
+                    run_step(config, step, base_path)
+    except StepFailedError as e:
+        print(str(e))
+        return 3
     return 0
 
 
diff --git a/setup.cfg b/setup.cfg
index fefd0f8..dcf0d2c 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -24,6 +24,7 @@ keywords = build, task
 [options]
 py_modules = bou
 python_requires = >=3.7
+install_requires = PyYAML
 
 [options.entry_points]
 console_scripts =