diff --git a/buildman/server.py b/buildman/server.py
index 2ad5be99d..f4a236155 100644
--- a/buildman/server.py
+++ b/buildman/server.py
@@ -132,9 +132,13 @@ class BuilderServer(object):
     logger.debug('Unregistering component with realm %s and token %s',
                   component.builder_realm, component.expected_token)
 
-    self._realm_map.pop(component.builder_realm)
-    self._current_components.remove(component)
-    self._session_factory.remove(component)
+    self._realm_map.pop(component.builder_realm, None)
+
+    if component in self._current_components:
+      self._current_components.remove(component)
+
+    if component in self._session_factory:
+      self._session_factory.remove(component)
 
   def _job_heartbeat(self, build_job):
     self._queue.extend_processing(build_job.job_item, seconds_from_now=JOB_TIMEOUT_SECONDS,
diff --git a/buildtrigger/githubhandler.py b/buildtrigger/githubhandler.py
index 8da48c1bb..aaaccd4d5 100644
--- a/buildtrigger/githubhandler.py
+++ b/buildtrigger/githubhandler.py
@@ -2,9 +2,14 @@ import logging
 import os.path
 import base64
 
-from app import app, github_trigger
+from functools import wraps
+from ssl import SSLError
+
+from github import (Github, UnknownObjectException, GithubException,
+                    BadCredentialsException as GitHubBadCredentialsException)
 from jsonschema import validate
 
+from app import app, github_trigger
 from buildtrigger.triggerutil import (RepositoryReadException, TriggerActivationException,
                                       TriggerDeactivationException, TriggerStartException,
                                       EmptyRepositoryException, ValidationRequestException,
@@ -13,13 +18,10 @@ from buildtrigger.triggerutil import (RepositoryReadException, TriggerActivation
                                       find_matching_branches)
 
 from buildtrigger.basehandler import BuildTriggerHandler
-
+from endpoints.exception import ExternalServiceError
 from util.security.ssh import generate_ssh_keypair
 from util.dict_wrappers import JSONPathDict, SafeDictSetter
 
-from github import (Github, UnknownObjectException, GithubException,
-                    BadCredentialsException as GitHubBadCredentialsException)
-
 logger = logging.getLogger(__name__)
 
 GITHUB_WEBHOOK_PAYLOAD_SCHEMA = {
@@ -139,6 +141,18 @@ def get_transformed_webhook_payload(gh_payload, default_branch=None, lookup_user
   return config.dict_value()
 
 
+def _catch_ssl_errors(func):
+  @wraps(func)
+  def wrapper(*args, **kwargs):
+    try:
+      return func(*args, **kwargs)
+    except SSLError as se:
+      msg = 'Request to the GitHub API failed: %s' % se.message
+      logger.exception(msg)
+      raise ExternalServiceError(msg)
+  return wrapper
+
+
 class GithubBuildTrigger(BuildTriggerHandler):
   """
   BuildTrigger for GitHub that uses the archive API and buildpacks.
@@ -169,6 +183,7 @@ class GithubBuildTrigger(BuildTriggerHandler):
 
     return default_msg
 
+  @_catch_ssl_errors
   def activate(self, standard_webhook_url):
     config = self.config
     new_build_source = config['build_source']
@@ -216,6 +231,7 @@ class GithubBuildTrigger(BuildTriggerHandler):
 
     return config, {'private_key': private_key}
 
+  @_catch_ssl_errors
   def deactivate(self):
     config = self.config
     gh_client = self._get_client()
@@ -256,6 +272,7 @@ class GithubBuildTrigger(BuildTriggerHandler):
     self.config = config
     return config
 
+  @_catch_ssl_errors
   def list_build_sources(self):
     gh_client = self._get_client()
     usr = gh_client.get_user()
@@ -306,6 +323,7 @@ class GithubBuildTrigger(BuildTriggerHandler):
     entries.sort(key=lambda e: e['info']['name'])
     return entries
 
+  @_catch_ssl_errors
   def list_build_subdirs(self):
     config = self.config
     gh_client = self._get_client()
@@ -331,6 +349,7 @@ class GithubBuildTrigger(BuildTriggerHandler):
 
       raise RepositoryReadException(message)
 
+  @_catch_ssl_errors
   def load_dockerfile_contents(self):
     config = self.config
     gh_client = self._get_client()
@@ -352,6 +371,7 @@ class GithubBuildTrigger(BuildTriggerHandler):
       message = ghe.data.get('message', 'Unable to read Dockerfile: %s' % source)
       raise RepositoryReadException(message)
 
+  @_catch_ssl_errors
   def list_field_values(self, field_name, limit=None):
     if field_name == 'refs':
       branches = self.list_field_values('branch_name')
@@ -444,6 +464,7 @@ class GithubBuildTrigger(BuildTriggerHandler):
       'commit_info': commit_info
     }
 
+  @_catch_ssl_errors
   def manual_start(self, run_parameters=None):
     config = self.config
     source = config['build_source']
@@ -474,6 +495,7 @@ class GithubBuildTrigger(BuildTriggerHandler):
     metadata = GithubBuildTrigger._build_metadata_for_commit(commit_sha, ref, repo)
     return self.prepare_build(metadata, is_manual=True)
 
+  @_catch_ssl_errors
   def lookup_user(self, username):
     try:
       gh_client = self._get_client()
@@ -485,6 +507,7 @@ class GithubBuildTrigger(BuildTriggerHandler):
     except GithubException:
       return None
 
+  @_catch_ssl_errors
   def handle_trigger_request(self, request):
     # Check the payload to see if we should skip it based on the lack of a head_commit.
     payload = request.get_json()
diff --git a/buildtrigger/gitlabhandler.py b/buildtrigger/gitlabhandler.py
index 47d288144..448fff4fc 100644
--- a/buildtrigger/gitlabhandler.py
+++ b/buildtrigger/gitlabhandler.py
@@ -14,7 +14,7 @@ from buildtrigger.basehandler import BuildTriggerHandler
 
 from util.security.ssh import generate_ssh_keypair
 from util.dict_wrappers import JSONPathDict, SafeDictSetter
-from endpoints.exception import ExternalServiceTimeout
+from endpoints.exception import ExternalServiceError
 
 import gitlab
 import requests
@@ -78,7 +78,7 @@ def _catch_timeouts(func):
     except requests.exceptions.Timeout:
       msg = 'Request to the GitLab API timed out'
       logger.exception(msg)
-      raise ExternalServiceTimeout(msg)
+      raise ExternalServiceError(msg)
   return wrapper
 
 
diff --git a/data/database.py b/data/database.py
index 83dbe74de..f07ad6592 100644
--- a/data/database.py
+++ b/data/database.py
@@ -305,13 +305,18 @@ get_epoch_timestamp_ms = lambda: int(time.time() * 1000)
 
 
 def close_db_filter(_):
-  if not db.is_closed():
-    logger.debug('Disconnecting from database.')
-    db.close()
+  try:
+    if not db.is_closed():
+      logger.debug('Disconnecting from database.')
+      db.close()
 
-  if read_slave.obj is not None and not read_slave.is_closed():
-    logger.debug('Disconnecting from read slave.')
-    read_slave.close()
+    if read_slave.obj is not None and not read_slave.is_closed():
+      logger.debug('Disconnecting from read slave.')
+      read_slave.close()
+  except AttributeError:
+    # If the database is closed between the time we check on line 309 and db.close() is called on
+    # 311, then an AttributeError will be raised. Simply eat this exception and continue onward.
+    pass
 
 
 class QuayUserField(ForeignKeyField):
diff --git a/data/model/__init__.py b/data/model/__init__.py
index 331b2f0b3..09521f9e4 100644
--- a/data/model/__init__.py
+++ b/data/model/__init__.py
@@ -96,6 +96,9 @@ class ServiceNameInvalid(DataModelException):
 class TagAlreadyCreatedException(DataModelException):
   pass
 
+class StaleTagException(DataModelException):
+  pass
+
 
 class TooManyLoginAttemptsException(Exception):
   def __init__(self, message, retry_after):
diff --git a/data/model/repository.py b/data/model/repository.py
index 6709b3f09..46de62bf7 100644
--- a/data/model/repository.py
+++ b/data/model/repository.py
@@ -54,7 +54,10 @@ def purge_repository(namespace_name, repository_name):
       not need to be checked or responded to.
       """
 
-  repo = _basequery.get_existing_repository(namespace_name, repository_name)
+  try:
+    repo = _basequery.get_existing_repository(namespace_name, repository_name)
+  except Repository.DoesNotExist:
+    return False
 
   # Delete all tags to allow gc to reclaim storage
   previously_referenced = tag.purge_all_tags(repo)
@@ -74,7 +77,11 @@ def purge_repository(namespace_name, repository_name):
     return False
 
   # Delete the rest of the repository metadata
-  fetched = _basequery.get_existing_repository(namespace_name, repository_name)
+  try:
+    fetched = _basequery.get_existing_repository(namespace_name, repository_name)
+  except Repository.DoesNotExist:
+    return False
+
   fetched.delete_instance(recursive=True, delete_nullable=False)
 
   return True
diff --git a/data/model/tag.py b/data/model/tag.py
index e5c3b3233..239bc3468 100644
--- a/data/model/tag.py
+++ b/data/model/tag.py
@@ -4,7 +4,7 @@ from uuid import uuid4
 
 from peewee import IntegrityError
 from data.model import (image, db_transaction, DataModelException, _basequery,
-                        InvalidManifestException, TagAlreadyCreatedException)
+                        InvalidManifestException, TagAlreadyCreatedException, StaleTagException)
 from data.database import (RepositoryTag, Repository, Image, ImageStorage, Namespace, TagManifest,
                            RepositoryNotification, Label, TagManifestLabel, get_epoch_timestamp,
                            db_for_update)
@@ -92,6 +92,9 @@ def create_or_update_tag(namespace_name, repository_name, tag_name, tag_docker_i
       tag.save()
     except RepositoryTag.DoesNotExist:
       pass
+    except IntegrityError:
+      msg = 'Tag with name %s was stale when we tried to update it; Please retry the push'
+      raise StaleTagException(msg % tag_name)
 
     try:
       image_obj = Image.get(Image.docker_image_id == tag_docker_image_id, Image.repository == repo)
diff --git a/data/model/team.py b/data/model/team.py
index 738a27407..753d00e2f 100644
--- a/data/model/team.py
+++ b/data/model/team.py
@@ -257,8 +257,13 @@ def get_organization_team_member_invites(teamid):
 
 
 def delete_team_email_invite(team, email):
-  found = TeamMemberInvite.get(TeamMemberInvite.email == email, TeamMemberInvite.team == team)
+  try:
+    found = TeamMemberInvite.get(TeamMemberInvite.email == email, TeamMemberInvite.team == team)
+  except TeamMemberInvite.DoesNotExist:
+    return False
+
   found.delete_instance()
+  return True
 
 
 def delete_team_user_invite(team, user_obj):
diff --git a/endpoints/api/build.py b/endpoints/api/build.py
index ae97571eb..ca7866f85 100644
--- a/endpoints/api/build.py
+++ b/endpoints/api/build.py
@@ -276,9 +276,12 @@ class RepositoryBuildList(RepositoryParamResource):
     if repo is None:
       raise NotFound()
 
-    build_name = (user_files.get_file_checksum(dockerfile_id)
-                  if dockerfile_id
-                  else hashlib.sha224(archive_url).hexdigest()[0:7])
+    try:
+      build_name = (user_files.get_file_checksum(dockerfile_id)
+                    if dockerfile_id
+                    else hashlib.sha224(archive_url).hexdigest()[0:7])
+    except IOError:
+      raise InvalidRequest('File %s could not be found or is invalid' %  dockerfile_id)
 
     prepared = PreparedBuild()
     prepared.build_name = build_name
diff --git a/endpoints/api/team.py b/endpoints/api/team.py
index a427c472a..81b779b58 100644
--- a/endpoints/api/team.py
+++ b/endpoints/api/team.py
@@ -347,7 +347,9 @@ class InviteTeamMember(ApiResource):
         raise NotFound()
 
       # Delete the invite.
-      model.team.delete_team_email_invite(team, email)
+      if not model.team.delete_team_email_invite(team, email):
+        raise NotFound()
+
       log_action('org_delete_team_member_invite', orgname, {
         'email': email,
         'team': teamname,
diff --git a/endpoints/exception.py b/endpoints/exception.py
index d11266153..dc37fd0fb 100644
--- a/endpoints/exception.py
+++ b/endpoints/exception.py
@@ -77,7 +77,7 @@ class ApiException(Exception):
     return rv
 
 
-class ExternalServiceTimeout(ApiException):
+class ExternalServiceError(ApiException):
   def __init__(self, error_description, payload=None):
     ApiException.__init__(self, ApiErrorType.external_service_timeout, 520, error_description, payload)
 
diff --git a/test/test_endpoints.py b/test/test_endpoints.py
index 256b54bd4..88da7270a 100644
--- a/test/test_endpoints.py
+++ b/test/test_endpoints.py
@@ -134,6 +134,9 @@ class WebEndpointTestCase(EndpointTestCase):
   def test_repo_view(self):
     self.getResponse('web.repository', path='devtable/simple')
 
+  def test_unicode_repo_view(self):
+    self.getResponse('web.repository', path='%E2%80%8Bcoreos/hyperkube%E2%80%8B')
+
   def test_org_view(self):
     self.getResponse('web.org_view', path='buynlarge')
 
diff --git a/util/names.py b/util/names.py
index e25eaa1c0..9fb6f3064 100644
--- a/util/names.py
+++ b/util/names.py
@@ -1,6 +1,8 @@
 import urllib
 import re
 
+import anunidecode # Don't listen to pylint's lies. This import is required for unidecode below.
+
 from uuid import uuid4
 
 REPOSITORY_NAME_REGEX = re.compile(r'^[\.a-zA-Z0-9_-]+$')
@@ -23,6 +25,8 @@ def escape_tag(tag, default='latest'):
 
 
 def parse_namespace_repository(repository, library_namespace, include_tag=False):
+  repository = repository.encode('unidecode', 'ignore')
+
   parts = repository.rstrip('/').split('/', 1)
   if len(parts) < 2:
     namespace = library_namespace