--- a/tools/tryselect/mach_commands.py
+++ b/tools/tryselect/mach_commands.py
@@ -1,35 +1,25 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 from __future__ import absolute_import, print_function, unicode_literals
 
-import os
-import sys
-from collections import defaultdict
+import argparse
 
 from mach.decorators import (
+    CommandArgument,
     CommandProvider,
     Command,
+    SubCommand,
 )
 
-import mozpack.path as mozpath
 from mozbuild.base import BuildEnvironmentNotFoundException, MachCommandBase
 
-CONFIG_ENVIRONMENT_NOT_FOUND = '''
-No config environment detected. This means we are unable to properly
-detect test files in the specified paths or tags. Please run:
-
-    $ mach configure
-
-and try again.
-'''.lstrip()
-
 
 def syntax_parser():
     from tryselect.selectors.syntax import arg_parser
     parser = arg_parser()
     # The --no-artifact flag is only interpreted locally by |mach try|; it's not
     # like the --artifact flag, which is interpreted remotely by the try server.
     #
     # We need a tri-state where set is different than the default value, so we
@@ -38,105 +28,45 @@ def syntax_parser():
                         dest='no_artifact',
                         action='store_true',
                         help='Force compiled (non-artifact) builds even when '
                              '--enable-artifact-builds is set.')
     return parser
 
 
 @CommandProvider
-class PushToTry(MachCommandBase):
-    def normalise_list(self, items, allow_subitems=False):
-        from tryselect.selectors.syntax import parse_arg
-
-        rv = defaultdict(list)
-        for item in items:
-            parsed = parse_arg(item)
-            for key, values in parsed.iteritems():
-                rv[key].extend(values)
-
-        if not allow_subitems:
-            if not all(item == [] for item in rv.itervalues()):
-                raise ValueError("Unexpected subitems in argument")
-            return rv.keys()
-        else:
-            return rv
-
-    def validate_args(self, **kwargs):
-        from tryselect.selectors.syntax import AutoTry
-
-        tests_selected = kwargs["tests"] or kwargs["paths"] or kwargs["tags"]
-        if kwargs["platforms"] is None and (kwargs["jobs"] is None or tests_selected):
-            if 'AUTOTRY_PLATFORM_HINT' in os.environ:
-                kwargs["platforms"] = [os.environ['AUTOTRY_PLATFORM_HINT']]
-            elif tests_selected:
-                print("Must specify platform when selecting tests.")
-                sys.exit(1)
-            else:
-                print("Either platforms or jobs must be specified as an argument to "
-                      "|mach try syntax|.")
-                sys.exit(1)
-
-        try:
-            platforms = (self.normalise_list(kwargs["platforms"])
-                         if kwargs["platforms"] else {})
-        except ValueError as e:
-            print("Error parsing -p argument:\n%s" % e.message)
-            sys.exit(1)
-
-        try:
-            tests = (self.normalise_list(kwargs["tests"], allow_subitems=True)
-                     if kwargs["tests"] else {})
-        except ValueError as e:
-            print("Error parsing -u argument (%s):\n%s" % (kwargs["tests"], e.message))
-            sys.exit(1)
-
-        try:
-            talos = (self.normalise_list(kwargs["talos"], allow_subitems=True)
-                     if kwargs["talos"] else [])
-        except ValueError as e:
-            print("Error parsing -t argument:\n%s" % e.message)
-            sys.exit(1)
-
-        try:
-            jobs = (self.normalise_list(kwargs["jobs"]) if kwargs["jobs"] else {})
-        except ValueError as e:
-            print("Error parsing -j argument:\n%s" % e.message)
-            sys.exit(1)
-
-        paths = []
-        for p in kwargs["paths"]:
-            p = mozpath.normpath(os.path.abspath(p))
-            if not (os.path.isdir(p) and p.startswith(self.topsrcdir)):
-                print('Specified path "%s" is not a directory under the srcdir,'
-                      ' unable to specify tests outside of the srcdir' % p)
-                sys.exit(1)
-            if len(p) <= len(self.topsrcdir):
-                print('Specified path "%s" is at the top of the srcdir and would'
-                      ' select all tests.' % p)
-                sys.exit(1)
-            paths.append(os.path.relpath(p, self.topsrcdir))
-
-        try:
-            tags = self.normalise_list(kwargs["tags"]) if kwargs["tags"] else []
-        except ValueError as e:
-            print("Error parsing --tags argument:\n%s" % e.message)
-            sys.exit(1)
-
-        extra_values = {k['dest'] for k in AutoTry.pass_through_arguments.values()}
-        extra_args = {k: v for k, v in kwargs.items()
-                      if k in extra_values and v}
-
-        return kwargs["builds"], platforms, tests, talos, jobs, paths, tags, extra_args
+class TrySelect(MachCommandBase):
 
     @Command('try',
-             category='testing',
-             description='Push selected tests to the try server',
-             parser=syntax_parser)
-    def syntax(self, **kwargs):
+             category='ci',
+             description='Push selected tasks to the try server')
+    @CommandArgument('args', nargs=argparse.REMAINDER)
+    def try_default(self, args):
+        """Push selected tests to the try server.
+
+        The |mach try| command is a frontend for scheduling tasks to
+        run on try server using selectors. A selector is a subcommand
+        that provides its own set of command line arguments and are
+        listed below. Currently there is only single selector called
+        `syntax`, but more selectors will be added in the future.
+
+        If no subcommand is specified, the `syntax` selector is run by
+        default. Run |mach try syntax --help| for more information on
+        scheduling with the `syntax` selector.
+        """
+        parser = syntax_parser()
+        kwargs = vars(parser.parse_args(args))
+        return self._mach_context.commands.dispatch(
+            'try', subcommand='syntax', context=self._mach_context, **kwargs)
+
+    @SubCommand('try',
+                'syntax',
+                description='Push selected tasks using try syntax',
+                parser=syntax_parser)
+    def try_syntax(self, **kwargs):
         """Push the current tree to try, with the specified syntax.
 
         Build options, platforms and regression tests may be selected
         using the usual try options (-b, -p and -u respectively). In
         addition, tests in a given directory may be automatically
         selected by passing that directory as a positional argument to the
         command. For example:
 
@@ -164,112 +94,25 @@ class PushToTry(MachCommandBase):
         scheduled. If no platform is selected a default is taken from
         the AUTOTRY_PLATFORM_HINT environment variable, if set.
 
         The command requires either its own mercurial extension ("push-to-try",
         installable from mach mercurial-setup) or a git repo using git-cinnabar
         (available at https://github.com/glandium/git-cinnabar).
 
         """
-
         from mozbuild.testing import TestResolver
         from tryselect.selectors.syntax import AutoTry
 
-        print("mach try is under development, please file bugs blocking 1149670.")
+        try:
+            if self.substs.get("MOZ_ARTIFACT_BUILDS"):
+                kwargs['local_artifact_build'] = True
+        except BuildEnvironmentNotFoundException:
+            # If we don't have a build locally, we can't tell whether
+            # an artifact build is desired, but we still want the
+            # command to succeed, if possible.
+            pass
 
         def resolver_func():
             return self._spawn(TestResolver)
 
         at = AutoTry(self.topsrcdir, resolver_func, self._mach_context)
-
-        if kwargs["list"]:
-            at.list_presets()
-            sys.exit()
-
-        if kwargs["load"] is not None:
-            defaults = at.load_config(kwargs["load"])
-
-            if defaults is None:
-                print("No saved configuration called %s found in autotry.ini" % kwargs["load"],
-                      file=sys.stderr)
-
-            for key, value in kwargs.iteritems():
-                if value in (None, []) and key in defaults:
-                    kwargs[key] = defaults[key]
-
-        if kwargs["push"] and at.find_uncommited_changes():
-            print('ERROR please commit changes before continuing')
-            sys.exit(1)
-
-        if not any(kwargs[item] for item in ("paths", "tests", "tags")):
-            kwargs["paths"], kwargs["tags"] = at.find_paths_and_tags(kwargs["verbose"])
-
-        builds, platforms, tests, talos, jobs, paths, tags, extra = self.validate_args(**kwargs)
-
-        if paths or tags:
-            if not os.path.exists(os.path.join(self.topobjdir, 'config.status')):
-                print(CONFIG_ENVIRONMENT_NOT_FOUND)
-                sys.exit(1)
-
-            paths = [os.path.relpath(os.path.normpath(os.path.abspath(item)), self.topsrcdir)
-                     for item in paths]
-            paths_by_flavor = at.paths_by_flavor(paths=paths, tags=tags)
-
-            if not paths_by_flavor and not tests:
-                print("No tests were found when attempting to resolve paths:\n\n\t%s" %
-                      paths)
-                sys.exit(1)
-
-            if not kwargs["intersection"]:
-                paths_by_flavor = at.remove_duplicates(paths_by_flavor, tests)
-        else:
-            paths_by_flavor = {}
-
-        # No point in dealing with artifacts if we aren't running any builds
-        local_artifact_build = False
-        if platforms:
-            try:
-                if self.substs.get("MOZ_ARTIFACT_BUILDS"):
-                    local_artifact_build = True
-            except BuildEnvironmentNotFoundException:
-                # If we don't have a build locally, we can't tell whether
-                # an artifact build is desired, but we still want the
-                # command to succeed, if possible.
-                pass
-
-            # Add --artifact if --enable-artifact-builds is set ...
-            if local_artifact_build:
-                extra["artifact"] = True
-            # ... unless --no-artifact is explicitly given.
-            if kwargs["no_artifact"]:
-                if "artifact" in extra:
-                    del extra["artifact"]
-
-        try:
-            msg = at.calc_try_syntax(platforms, tests, talos, jobs, builds, paths_by_flavor, tags,
-                                     extra, kwargs["intersection"])
-        except ValueError as e:
-            print(e.message)
-            sys.exit(1)
-
-        if local_artifact_build:
-            if kwargs["no_artifact"]:
-                print('mozconfig has --enable-artifact-builds but '
-                      '--no-artifact specified, not including --artifact '
-                      'flag in try syntax')
-            else:
-                print('mozconfig has --enable-artifact-builds; including '
-                      '--artifact flag in try syntax (use --no-artifact '
-                      'to override)')
-
-        if kwargs["verbose"] and paths_by_flavor:
-            print('The following tests will be selected: ')
-            for flavor, paths in paths_by_flavor.iteritems():
-                print("%s: %s" % (flavor, ",".join(paths)))
-
-        if kwargs["verbose"] or not kwargs["push"]:
-            print('The following try syntax was calculated:\n%s' % msg)
-
-        if kwargs["push"]:
-            at.push_to_try(msg, kwargs["verbose"])
-
-        if kwargs["save"] is not None:
-            at.save_config(kwargs["save"], msg)
+        return at.run(**kwargs)

--- a/tools/tryselect/selectors/syntax.py
+++ b/tools/tryselect/selectors/syntax.py
@@ -1,22 +1,33 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
+from __future__ import absolute_import, print_function, unicode_literals
+
+import ConfigParser
 import argparse
 import os
 import re
 import subprocess
 import sys
 import which
-
 from collections import defaultdict
 
-import ConfigParser
+import mozpack.path as mozpath
+
+CONFIG_ENVIRONMENT_NOT_FOUND = '''
+No config environment detected. This means we are unable to properly
+detect test files in the specified paths or tags. Please run:
+
+    $ mach configure
+
+and try again.
+'''.lstrip()
 
 
 def arg_parser():
     parser = argparse.ArgumentParser()
     parser.add_argument('paths', nargs='*', help='Paths to search for tests to run on try.')
     parser.add_argument('-b', '--build', dest='builds', default='do',
                         help='Build types to run (d for debug, o for optimized).')
     parser.add_argument('-p', '--platform', dest='platforms', action='append',
@@ -608,8 +619,174 @@ class AutoTry(object):
             if verbose:
                 if paths:
                     print("Pushing tests based on the following patterns:\n\t%s" %
                           "\n\t".join(paths))
                 if tags:
                     print("Pushing tests based on the following tags:\n\t%s" %
                           "\n\t".join(tags))
         return paths, tags
+
+    def normalise_list(self, items, allow_subitems=False):
+        rv = defaultdict(list)
+        for item in items:
+            parsed = parse_arg(item)
+            for key, values in parsed.iteritems():
+                rv[key].extend(values)
+
+        if not allow_subitems:
+            if not all(item == [] for item in rv.itervalues()):
+                raise ValueError("Unexpected subitems in argument")
+            return rv.keys()
+        else:
+            return rv
+
+    def validate_args(self, **kwargs):
+        tests_selected = kwargs["tests"] or kwargs["paths"] or kwargs["tags"]
+        if kwargs["platforms"] is None and (kwargs["jobs"] is None or tests_selected):
+            if 'AUTOTRY_PLATFORM_HINT' in os.environ:
+                kwargs["platforms"] = [os.environ['AUTOTRY_PLATFORM_HINT']]
+            elif tests_selected:
+                print("Must specify platform when selecting tests.")
+                sys.exit(1)
+            else:
+                print("Either platforms or jobs must be specified as an argument to autotry.")
+                sys.exit(1)
+
+        try:
+            platforms = (self.normalise_list(kwargs["platforms"])
+                         if kwargs["platforms"] else {})
+        except ValueError as e:
+            print("Error parsing -p argument:\n%s" % e.message)
+            sys.exit(1)
+
+        try:
+            tests = (self.normalise_list(kwargs["tests"], allow_subitems=True)
+                     if kwargs["tests"] else {})
+        except ValueError as e:
+            print("Error parsing -u argument (%s):\n%s" % (kwargs["tests"], e.message))
+            sys.exit(1)
+
+        try:
+            talos = (self.normalise_list(kwargs["talos"], allow_subitems=True)
+                     if kwargs["talos"] else [])
+        except ValueError as e:
+            print("Error parsing -t argument:\n%s" % e.message)
+            sys.exit(1)
+
+        try:
+            jobs = (self.normalise_list(kwargs["jobs"]) if kwargs["jobs"] else {})
+        except ValueError as e:
+            print("Error parsing -j argument:\n%s" % e.message)
+            sys.exit(1)
+
+        paths = []
+        for p in kwargs["paths"]:
+            p = mozpath.normpath(os.path.abspath(p))
+            if not (os.path.isdir(p) and p.startswith(self.topsrcdir)):
+                print('Specified path "%s" is not a directory under the srcdir,'
+                      ' unable to specify tests outside of the srcdir' % p)
+                sys.exit(1)
+            if len(p) <= len(self.topsrcdir):
+                print('Specified path "%s" is at the top of the srcdir and would'
+                      ' select all tests.' % p)
+                sys.exit(1)
+            paths.append(os.path.relpath(p, self.topsrcdir))
+
+        try:
+            tags = self.normalise_list(kwargs["tags"]) if kwargs["tags"] else []
+        except ValueError as e:
+            print("Error parsing --tags argument:\n%s" % e.message)
+            sys.exit(1)
+
+        extra_values = {k['dest'] for k in AutoTry.pass_through_arguments.values()}
+        extra_args = {k: v for k, v in kwargs.items()
+                      if k in extra_values and v}
+
+        return kwargs["builds"], platforms, tests, talos, jobs, paths, tags, extra_args
+
+    def run(self, **kwargs):
+        if kwargs["list"]:
+            self.list_presets()
+            sys.exit()
+
+        if kwargs["load"] is not None:
+            defaults = self.load_config(kwargs["load"])
+
+            if defaults is None:
+                print("No saved configuration called %s found in autotry.ini" % kwargs["load"],
+                      file=sys.stderr)
+
+            for key, value in kwargs.iteritems():
+                if value in (None, []) and key in defaults:
+                    kwargs[key] = defaults[key]
+
+        if kwargs["push"] and self.find_uncommited_changes():
+            print('ERROR please commit changes before continuing')
+            sys.exit(1)
+
+        if not any(kwargs[item] for item in ("paths", "tests", "tags")):
+            kwargs["paths"], kwargs["tags"] = self.find_paths_and_tags(kwargs["verbose"])
+
+        builds, platforms, tests, talos, jobs, paths, tags, extra = self.validate_args(**kwargs)
+
+        if paths or tags:
+            if not os.path.exists(os.path.join(self.topobjdir, 'config.status')):
+                print(CONFIG_ENVIRONMENT_NOT_FOUND)
+                sys.exit(1)
+
+            paths = [os.path.relpath(os.path.normpath(os.path.abspath(item)), self.topsrcdir)
+                     for item in paths]
+            paths_by_flavor = self.paths_by_flavor(paths=paths, tags=tags)
+
+            if not paths_by_flavor and not tests:
+                print("No tests were found when attempting to resolve paths:\n\n\t%s" %
+                      paths)
+                sys.exit(1)
+
+            if not kwargs["intersection"]:
+                paths_by_flavor = self.remove_duplicates(paths_by_flavor, tests)
+        else:
+            paths_by_flavor = {}
+
+        # No point in dealing with artifacts if we aren't running any builds
+        local_artifact_build = False
+        if platforms:
+            local_artifact_build = kwargs.get('local_artifact_build', False)
+
+            # Add --artifact if --enable-artifact-builds is set ...
+            if local_artifact_build:
+                extra["artifact"] = True
+            # ... unless --no-artifact is explicitly given.
+            if kwargs["no_artifact"]:
+                if "artifact" in extra:
+                    del extra["artifact"]
+
+        try:
+            msg = self.calc_try_syntax(platforms, tests, talos, jobs, builds,
+                                       paths_by_flavor, tags, extra, kwargs["intersection"])
+        except ValueError as e:
+            print(e.message)
+            sys.exit(1)
+
+        if local_artifact_build:
+            if kwargs["no_artifact"]:
+                print('mozconfig has --enable-artifact-builds but '
+                      '--no-artifact specified, not including --artifact '
+                      'flag in try syntax')
+            else:
+                print('mozconfig has --enable-artifact-builds; including '
+                      '--artifact flag in try syntax (use --no-artifact '
+                      'to override)')
+
+        if kwargs["verbose"] and paths_by_flavor:
+            print('The following tests will be selected: ')
+            for flavor, paths in paths_by_flavor.iteritems():
+                print("%s: %s" % (flavor, ",".join(paths)))
+
+        if kwargs["verbose"] or not kwargs["push"]:
+            print('The following try syntax was calculated:\n%s' % msg)
+
+        if kwargs["push"]:
+            self.push_to_try(msg, kwargs["verbose"])
+
+        if kwargs["save"] is not None:
+            self.save_config(kwargs["save"], msg)