diff --git a/setup.py b/setup.py
index 1501fdc..b0e9f72 100644
--- a/setup.py
+++ b/setup.py
@@ -9,8 +9,7 @@ setup(
     author_email='roman.zeyde@gmail.com',
     url='http://github.com/romanz/trezor-agent',
     packages=['trezor_agent', 'trezor_agent.gpg'],
-    install_requires=['ecdsa>=0.13', 'ed25519>=1.4', 'Cython>=0.23.4', 'protobuf>=3.0.0', 'trezor>=0.7.4', 'semver>=2.2',
-                      'keepkey>=0.7.3'],
+    install_requires=['ecdsa>=0.13', 'ed25519>=1.4', 'Cython>=0.23.4', 'protobuf>=3.0.0', 'trezor>=0.7.4', 'semver>=2.2'],
     platforms=['POSIX'],
     classifiers=[
         'Environment :: Console',
@@ -28,6 +27,10 @@ setup(
         'Topic :: Security',
         'Topic :: Utilities',
     ],
+    extras_require={
+        'trezorlib': ['python-trezor>=0.7.4'],
+        'keepkeylib': ['keepkey>=0.7.3'],
+    },
     entry_points={'console_scripts': [
         'trezor-agent = trezor_agent.__main__:run_agent',
         'trezor-git = trezor_agent.__main__:run_git',
diff --git a/trezor_agent/factory.py b/trezor_agent/factory.py
index 50da0f3..fb97509 100644
--- a/trezor_agent/factory.py
+++ b/trezor_agent/factory.py
@@ -92,8 +92,9 @@ def load(loaders=None):
         device = loader()
         if device:
             device_list.extend(device)
+            break   # stop polling if we found the device...
 
-    if len(device_list) == 1:
+    if len(device_list) == 1:   # ...especialy when we need exactly one
         return device_list[0]
 
     msg = '{:d} devices found'.format(len(device_list))
diff --git a/trezor_agent/gpg/keyring.py b/trezor_agent/gpg/keyring.py
index eeea055..caf9cdf 100644
--- a/trezor_agent/gpg/keyring.py
+++ b/trezor_agent/gpg/keyring.py
@@ -18,7 +18,7 @@ def get_agent_sock_path(sp=subprocess):
     """Parse gpgconf output to find out GPG agent UNIX socket path."""
     lines = sp.check_output(['gpgconf', '--list-dirs']).strip().split(b'\n')
     dirs = dict(line.split(b':', 1) for line in lines)
-    return dirs['agent-socket']
+    return dirs[b'agent-socket']
 
 
 def connect_to_agent(sp=subprocess):