--- a/devtools/moz.build
+++ b/devtools/moz.build
@@ -15,17 +15,17 @@ if CONFIG['MOZ_DEVTOOLS'] == 'all':
 DIRS += [
     'server',
     'shared',
 ]
 
 # /browser uses DIST_SUBDIR.  We opt-in to this treatment when building
 # DevTools for the browser to keep the root omni.ja slim for use by external XUL
 # apps.  Mulet also uses this since it includes /browser.
-if CONFIG['MOZ_BUILD_APP'] in ('browser', 'b2g/dev'):
+if CONFIG['MOZ_BUILD_APP'] == 'browser':
     DIST_SUBDIR = 'browser'
     export('DIST_SUBDIR')
 
 with Files('**'):
     BUG_COMPONENT = ('Firefox', 'Developer Tools')
 
 with Files('docs/**'):
     BUG_COMPONENT = ('Firefox', 'Developer Tools')

--- a/python/mozbuild/mozbuild/action/test_archive.py
+++ b/python/mozbuild/mozbuild/action/test_archive.py
@@ -418,17 +418,16 @@ ARCHIVE_FILES = {
             'patterns': [
                 'head.js',
                 'mach_test_package_commands.py',
                 'moz-http2/**',
                 'moz-spdy/**',
                 'node-http2/**',
                 'node-spdy/**',
                 'remotexpcshelltests.py',
-                'runtestsb2g.py',
                 'runxpcshelltests.py',
                 'xpcshellcommandline.py',
             ],
             'dest': 'xpcshell',
         },
         {
             'source': STAGE,
             'base': '',

--- a/python/mozbuild/mozbuild/base.py
+++ b/python/mozbuild/mozbuild/base.py
@@ -730,47 +730,23 @@ class MachCommandConditions(object):
     @staticmethod
     def is_firefox(cls):
         """Must have a Firefox build."""
         if hasattr(cls, 'substs'):
             return cls.substs.get('MOZ_BUILD_APP') == 'browser'
         return False
 
     @staticmethod
-    def is_mulet(cls):
-        """Must have a Mulet build."""
-        if hasattr(cls, 'substs'):
-            return cls.substs.get('MOZ_BUILD_APP') == 'b2g/dev'
-        return False
-
-    @staticmethod
     def is_b2g(cls):
         """Must have a B2G build."""
         if hasattr(cls, 'substs'):
             return cls.substs.get('MOZ_WIDGET_TOOLKIT') == 'gonk'
         return False
 
     @staticmethod
-    def is_b2g_desktop(cls):
-        """Must have a B2G desktop build."""
-        if hasattr(cls, 'substs'):
-            return cls.substs.get('MOZ_BUILD_APP') == 'b2g' and \
-                   cls.substs.get('MOZ_WIDGET_TOOLKIT') != 'gonk'
-        return False
-
-    @staticmethod
-    def is_emulator(cls):
-        """Must have a B2G build with an emulator configured."""
-        try:
-            return MachCommandConditions.is_b2g(cls) and \
-                   cls.device_name.startswith('emulator')
-        except AttributeError:
-            return False
-
-    @staticmethod
     def is_android(cls):
         """Must have an Android build."""
         if hasattr(cls, 'substs'):
             return cls.substs.get('MOZ_WIDGET_TOOLKIT') == 'android'
         return False
 
     @staticmethod
     def is_hg(cls):

--- a/python/mozbuild/mozbuild/mozinfo.py
+++ b/python/mozbuild/mozbuild/mozinfo.py
@@ -107,24 +107,16 @@ def build_dict(config, env=os.environ):
             if d['buildapp'] == 'mulet':
                 p = '{}-mulet'.format(p)
 
             if d['asan']:
                 p = '{}-asan'.format(p)
 
             return p
 
-        if d['buildapp'] == 'b2g':
-            if d['toolkit'] == 'gonk':
-                return 'emulator'
-
-            if d['bits'] == 64:
-                return 'linux64_gecko'
-            return 'linux32_gecko'
-
         if d['buildapp'] == 'mobile/android':
             if d['processor'] == 'x86':
                 return 'android-x86'
             return 'android-arm'
 
     def guess_buildtype():
         if d['debug']:
             return 'debug'

--- a/python/mozbuild/mozbuild/test/configure/lint.py
+++ b/python/mozbuild/mozbuild/test/configure/lint.py
@@ -22,19 +22,16 @@ test_path = os.path.abspath(__file__)
 class LintMeta(type):
     def __new__(mcs, name, bases, attrs):
         def create_test(project, func):
             def test(self):
                 return func(self, project)
             return test
 
         for project in (
-            'b2g',
-            'b2g/dev',
-            'b2g/graphene',
             'browser',
             'embedding/ios',
             'extensions',
             'js',
             'mobile/android',
         ):
             attrs['test_%s' % project.replace('/', '_')] = create_test(
                 project, attrs['lint'])

--- a/python/mozbuild/mozbuild/test/frontend/data/test-manifest-keys-extracted/chrome.ini
+++ b/python/mozbuild/mozbuild/test/frontend/data/test-manifest-keys-extracted/chrome.ini
@@ -1,4 +1,3 @@
 [DEFAULT]
-skip-if = buildapp == 'b2g'
 
 [test_chrome.js]