Quark uses and relies upon the transaction module, something at the end of the wsgi request needs to commit the transaction, or transaction aware databases (MySQL InnoDB, Postgres, et. al) will never commit.
The following neutron api-paste.ini enables repoze.tm2 to in the pipeline after authentication so transactions are started coming up the pipeline and commited coming down
[composite:neutron]
use = egg:Paste#urlmap
/: neutronversions
/v2.0: neutronapi_v2_0
[composite:neutronapi_v2_0]
use = call:neutron.auth:pipeline_factory
noauth = egg:repoze.tm2#tm extensions neutronapiapp_v2_0
keystone = authtoken keystonecontext egg:repoze.tm2#tm extensions neutronapiapp_v2_0
[filter:keystonecontext]
paste.filter_factory = neutron.auth:NeutronKeystoneContext.factory
[filter:authtoken]
paste.filter_factory = keystoneclient.middleware.auth_token:filter_factory
[filter:extensions]
paste.filter_factory = neutron.api.extensions:plugin_aware_extension_middleware_factory
[app:neutronversions]
paste.app_factory = neutron.api.versions:Versions.factory
[app:neutronapiapp_v2_0]
paste.app_factory = neutron.api.v2.router:APIRouter.factory