diff --git a/buildbot/master/files/config/factories.py b/buildbot/master/files/config/factories.py
index 00e45587..aca9b747 100644
--- a/buildbot/master/files/config/factories.py
+++ b/buildbot/master/files/config/factories.py
@@ -59,16 +59,13 @@ class DynamicServoFactory(ServoFactory):
     def __init__(self, builder_name, environment):
         self.environment = environment
         self.is_windows = re.match('windows.*', builder_name) is not None
-        try:
-            config_dir = os.path.dirname(os.path.realpath(__file__))
-            yaml_path = os.path.join(config_dir, 'steps.yml')
-            with open(yaml_path) as steps_file:
-                builder_steps = yaml.safe_load(steps_file)
-            commands = builder_steps[builder_name]
-            dynamic_steps = [self.make_step(command) for command in commands]
-        except Exception as e:  # Bad step configuration, fail build
-            print(str(e))
-            dynamic_steps = [BadConfigurationStep(e)]
+        self.builder_name = builder_name
+        config_dir = os.path.dirname(os.path.realpath(__file__))
+        yaml_path = os.path.join(config_dir, 'steps.yml')
+        with open(yaml_path) as steps_file:
+            builder_steps = yaml.safe_load(steps_file)
+        commands = builder_steps[builder_name]
+        dynamic_steps = [self.make_step(command) for command in commands]
 
         pkill_step = [self.make_pkill_step("servo")]
 
@@ -85,6 +82,13 @@ def make_step(self, command):
         # Add bash -l before every command on Windows builders
         bash_args = ["bash", "-l"] if self.is_windows else []
         step_kwargs['command'] = bash_args + command
+        if self.is_windows:
+            step_env += envs.Environment({
+                # Set home directory, to avoid adding `cd` command every time
+                'HOME': r'C:\buildbot\slave\{}\build'.format(
+                    self.builder_name
+                ),
+            })
 
         step_class = steps.ShellCommand
         args = iter(command)
@@ -109,6 +113,17 @@ def make_step(self, command):
             elif arg == './etc/ci/upload_nightly.sh':
                 step_kwargs['logEnviron'] = False
                 step_env += envs.upload_nightly
+                if self.is_windows:
+                    # s3cmd on Windows only works within msys
+                    step_env['MSYSTEM'] = 'MSYS'
+                    step_env['PATH'] = ';'.join([
+                        r'C:\msys64\usr\bin',
+                        r'C:\Windows\system32',
+                        r'C:\Windows',
+                        r'C:\Windows\System32\Wbem',
+                        r'C:\Windows\System32\WindowsPowerShell\v1.0',
+                        r'C:\Program Files\Amazon\cfn-bootstrap',
+                    ])
 
         step_kwargs['env'] = step_env
         return step_class(**step_kwargs)
@@ -182,9 +197,12 @@ def make_step(self, command):
         # Add bash -l before every command on Windows builders
         bash_command = ["bash", "-l"] if self.is_windows else []
         step_kwargs['command'] = bash_command + command
-        step_env += envs.Environment({
-            # Set home directory, to avoid adding `cd` command on every command
-            'HOME': r'C:\buildbot\slave\{}\build'.format(self.builder_name),
+        if self.is_windows:
+            step_env += envs.Environment({
+                # Set home directory, to avoid adding `cd` command every time
+                'HOME': r'C:\buildbot\slave\{}\build'.format(
+                    self.builder_name
+                ),
             })
 
         step_class = steps.ShellCommand
@@ -210,6 +228,17 @@ def make_step(self, command):
             elif arg == './etc/ci/upload_nightly.sh':
                 step_kwargs['logEnviron'] = False
                 step_env += envs.upload_nightly
+                if self.is_windows:
+                    # s3cmd on Windows only works within msys
+                    step_env['MSYSTEM'] = 'MSYS'
+                    step_env['PATH'] = ';'.join([
+                        r'C:\msys64\usr\bin',
+                        r'C:\Windows\system32',
+                        r'C:\Windows',
+                        r'C:\Windows\System32\Wbem',
+                        r'C:\Windows\System32\WindowsPowerShell\v1.0',
+                        r'C:\Program Files\Amazon\cfn-bootstrap',
+                    ])
 
         step_kwargs['env'] = step_env
         return step_class(**step_kwargs)
diff --git a/homu/files/cfg.toml b/homu/files/cfg.toml
index 881cd126..be4a87e9 100644
--- a/homu/files/cfg.toml
+++ b/homu/files/cfg.toml
@@ -124,8 +124,8 @@ secret = "{{ pillar["homu"]["gh-webhook-secret"] }}"
 [repo.servo.buildbot]
 url = "http://build.servo.org"
 secret = "{{ pillar["homu"]["buildbot-secret"] }}"
-builders = ["linux-dev", "linux-rel", "android", "mac-dev-unit", "mac-rel-wpt", "mac-rel-css", "arm32", "arm64", "windows"]
-try_builders = ["linux-dev", "linux-rel", "android", "mac-dev-unit", "mac-rel-wpt", "mac-rel-css", "arm32", "arm64", "windows"]
+builders = ["linux-dev", "linux-rel", "android", "mac-dev-unit", "mac-rel-wpt", "mac-rel-css", "arm32", "arm64", "windows-dev"]
+try_builders = ["linux-dev", "linux-rel", "android", "mac-dev-unit", "mac-rel-wpt", "mac-rel-css", "arm32", "arm64", "windows-dev"]
 username = "{{ pillar["homu"]["buildbot-http-user"] }}"
 password = "{{ pillar["homu"]["buildbot-http-pass"] }}"