diff --git a/mistral/api/controllers/v2/action.py b/mistral/api/controllers/v2/action.py
index 19093bd2c..b1e6b837a 100644
--- a/mistral/api/controllers/v2/action.py
+++ b/mistral/api/controllers/v2/action.py
@@ -28,10 +28,10 @@ from mistral.api.hooks import content_type as ct_hook
 from mistral import context
 from mistral.db.v2 import api as db_api
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral.services import actions
 from mistral.utils import filter_utils
 from mistral.utils import rest_utils
-from mistral.workbook import parser as spec_parser
 
 LOG = logging.getLogger(__name__)
 
diff --git a/mistral/api/controllers/v2/task.py b/mistral/api/controllers/v2/task.py
index 72b3a0f5b..42ee7171d 100644
--- a/mistral/api/controllers/v2/task.py
+++ b/mistral/api/controllers/v2/task.py
@@ -28,9 +28,9 @@ from mistral import context
 from mistral.db.v2 import api as db_api
 from mistral.engine.rpc_backend import rpc
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral.utils import filter_utils
 from mistral.utils import rest_utils
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import data_flow
 from mistral.workflow import states
 
diff --git a/mistral/api/controllers/v2/workbook.py b/mistral/api/controllers/v2/workbook.py
index cf18d1e3b..bee4d9136 100644
--- a/mistral/api/controllers/v2/workbook.py
+++ b/mistral/api/controllers/v2/workbook.py
@@ -27,10 +27,10 @@ from mistral.api.controllers.v2 import validation
 from mistral.api.hooks import content_type as ct_hook
 from mistral import context
 from mistral.db.v2 import api as db_api
+from mistral.lang import parser as spec_parser
 from mistral.services import workbooks
 from mistral.utils import filter_utils
 from mistral.utils import rest_utils
-from mistral.workbook import parser as spec_parser
 
 
 LOG = logging.getLogger(__name__)
diff --git a/mistral/api/controllers/v2/workflow.py b/mistral/api/controllers/v2/workflow.py
index 7e8a2e8c6..c0202e883 100644
--- a/mistral/api/controllers/v2/workflow.py
+++ b/mistral/api/controllers/v2/workflow.py
@@ -31,10 +31,10 @@ from mistral.api.hooks import content_type as ct_hook
 from mistral import context
 from mistral.db.v2 import api as db_api
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral.services import workflows
 from mistral.utils import filter_utils
 from mistral.utils import rest_utils
-from mistral.workbook import parser as spec_parser
 
 
 LOG = logging.getLogger(__name__)
diff --git a/mistral/engine/action_handler.py b/mistral/engine/action_handler.py
index a1791d1e2..96c66c8e6 100644
--- a/mistral/engine/action_handler.py
+++ b/mistral/engine/action_handler.py
@@ -21,7 +21,7 @@ from mistral.db.v2.sqlalchemy import models
 from mistral.engine import actions
 from mistral.engine import task_handler
 from mistral import exceptions as exc
-from mistral.workbook import parser as spec_parser
+from mistral.lang import parser as spec_parser
 
 
 LOG = logging.getLogger(__name__)
diff --git a/mistral/engine/actions.py b/mistral/engine/actions.py
index c63f05add..69d6ffcd2 100644
--- a/mistral/engine/actions.py
+++ b/mistral/engine/actions.py
@@ -25,11 +25,11 @@ from mistral.engine import utils as e_utils
 from mistral.engine import workflow_handler as wf_handler
 from mistral import exceptions as exc
 from mistral import expressions as expr
+from mistral.lang import parser as spec_parser
 from mistral.services import action_manager as a_m
 from mistral.services import security
 from mistral import utils
 from mistral.utils import wf_trace
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import states
 from mistral.workflow import utils as wf_utils
 
diff --git a/mistral/engine/task_handler.py b/mistral/engine/task_handler.py
index 5cc77553f..f45b512fe 100644
--- a/mistral/engine/task_handler.py
+++ b/mistral/engine/task_handler.py
@@ -25,8 +25,8 @@ from mistral.engine import action_queue
 from mistral.engine import tasks
 from mistral.engine import workflow_handler as wf_handler
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral.services import scheduler
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import base as wf_base
 from mistral.workflow import commands as wf_cmds
 from mistral.workflow import states
diff --git a/mistral/engine/workflows.py b/mistral/engine/workflows.py
index eb09012dc..ee58d8917 100644
--- a/mistral/engine/workflows.py
+++ b/mistral/engine/workflows.py
@@ -25,12 +25,12 @@ from mistral.engine import dispatcher
 from mistral.engine.rpc_backend import rpc
 from mistral.engine import utils as eng_utils
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral.services import scheduler
 from mistral.services import workflows as wf_service
 from mistral import utils
 from mistral.utils import merge_dicts
 from mistral.utils import wf_trace
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import base as wf_base
 from mistral.workflow import commands
 from mistral.workflow import data_flow
diff --git a/mistral/tests/unit/workbook/__init__.py b/mistral/lang/__init__.py
similarity index 100%
rename from mistral/tests/unit/workbook/__init__.py
rename to mistral/lang/__init__.py
diff --git a/mistral/workbook/base.py b/mistral/lang/base.py
similarity index 99%
rename from mistral/workbook/base.py
rename to mistral/lang/base.py
index 0c8c06e6d..28d6b02aa 100644
--- a/mistral/workbook/base.py
+++ b/mistral/lang/base.py
@@ -21,8 +21,8 @@ import six
 
 from mistral import exceptions as exc
 from mistral import expressions as expr
+from mistral.lang import types
 from mistral import utils
-from mistral.workbook import types
 
 
 CMD_PTRN = re.compile("^[\w\.]+[^=\(\s\"]*")
diff --git a/mistral/workbook/parser.py b/mistral/lang/parser.py
similarity index 96%
rename from mistral/workbook/parser.py
rename to mistral/lang/parser.py
index e9d4408c4..3cf595d56 100644
--- a/mistral/workbook/parser.py
+++ b/mistral/lang/parser.py
@@ -22,11 +22,11 @@ import six
 
 from mistral.db.v2 import api as db_api
 from mistral import exceptions as exc
-from mistral.workbook import base
-from mistral.workbook.v2 import actions as actions_v2
-from mistral.workbook.v2 import tasks as tasks_v2
-from mistral.workbook.v2 import workbook as wb_v2
-from mistral.workbook.v2 import workflows as wf_v2
+from mistral.lang import base
+from mistral.lang.v2 import actions as actions_v2
+from mistral.lang.v2 import tasks as tasks_v2
+from mistral.lang.v2 import workbook as wb_v2
+from mistral.lang.v2 import workflows as wf_v2
 
 V2_0 = '2.0'
 
diff --git a/mistral/workbook/types.py b/mistral/lang/types.py
similarity index 100%
rename from mistral/workbook/types.py
rename to mistral/lang/types.py
diff --git a/mistral/tests/unit/workbook/v2/__init__.py b/mistral/lang/v2/__init__.py
similarity index 100%
rename from mistral/tests/unit/workbook/v2/__init__.py
rename to mistral/lang/v2/__init__.py
diff --git a/mistral/workbook/v2/actions.py b/mistral/lang/v2/actions.py
similarity index 97%
rename from mistral/workbook/v2/actions.py
rename to mistral/lang/v2/actions.py
index 469c663b7..529ff6dbc 100644
--- a/mistral/workbook/v2/actions.py
+++ b/mistral/lang/v2/actions.py
@@ -15,9 +15,9 @@
 
 import six
 
+from mistral.lang import types
+from mistral.lang.v2 import base
 from mistral import utils
-from mistral.workbook import types
-from mistral.workbook.v2 import base
 
 
 class ActionSpec(base.BaseSpec):
diff --git a/mistral/workbook/v2/base.py b/mistral/lang/v2/base.py
similarity index 94%
rename from mistral/workbook/v2/base.py
rename to mistral/lang/v2/base.py
index 0c9b48565..b3a31fad3 100644
--- a/mistral/workbook/v2/base.py
+++ b/mistral/lang/v2/base.py
@@ -12,8 +12,8 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-from mistral.workbook import base
-from mistral.workbook import types
+from mistral.lang import base
+from mistral.lang import types
 
 
 class BaseSpec(base.BaseSpec):
diff --git a/mistral/workbook/v2/policies.py b/mistral/lang/v2/policies.py
similarity index 95%
rename from mistral/workbook/v2/policies.py
rename to mistral/lang/v2/policies.py
index e2d8b83da..e83c44063 100644
--- a/mistral/workbook/v2/policies.py
+++ b/mistral/lang/v2/policies.py
@@ -13,9 +13,9 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-from mistral.workbook import types
-from mistral.workbook.v2 import base
-from mistral.workbook.v2 import retry_policy
+from mistral.lang import types
+from mistral.lang.v2 import base
+from mistral.lang.v2 import retry_policy
 
 
 RETRY_SCHEMA = retry_policy.RetrySpec.get_schema(includes=None)
diff --git a/mistral/workbook/v2/retry_policy.py b/mistral/lang/v2/retry_policy.py
similarity index 97%
rename from mistral/workbook/v2/retry_policy.py
rename to mistral/lang/v2/retry_policy.py
index b46176588..2eeffe1bb 100644
--- a/mistral/workbook/v2/retry_policy.py
+++ b/mistral/lang/v2/retry_policy.py
@@ -15,8 +15,8 @@
 
 import six
 
-from mistral.workbook import types
-from mistral.workbook.v2 import base
+from mistral.lang import types
+from mistral.lang.v2 import base
 
 
 class RetrySpec(base.BaseSpec):
diff --git a/mistral/workbook/v2/task_defaults.py b/mistral/lang/v2/task_defaults.py
similarity index 95%
rename from mistral/workbook/v2/task_defaults.py
rename to mistral/lang/v2/task_defaults.py
index 6cb48b0dc..820e32fd8 100644
--- a/mistral/workbook/v2/task_defaults.py
+++ b/mistral/lang/v2/task_defaults.py
@@ -15,10 +15,10 @@
 
 import six
 
-from mistral.workbook import types
-from mistral.workbook.v2 import base
-from mistral.workbook.v2 import policies
-from mistral.workbook.v2 import tasks
+from mistral.lang import types
+from mistral.lang.v2 import base
+from mistral.lang.v2 import policies
+from mistral.lang.v2 import tasks
 
 
 direct_wf_ts = tasks.DirectWorkflowTaskSpec
diff --git a/mistral/workbook/v2/tasks.py b/mistral/lang/v2/tasks.py
similarity index 98%
rename from mistral/workbook/v2/tasks.py
rename to mistral/lang/v2/tasks.py
index 0342c46ce..065a70d86 100644
--- a/mistral/workbook/v2/tasks.py
+++ b/mistral/lang/v2/tasks.py
@@ -20,10 +20,10 @@ import six
 
 from mistral import exceptions as exc
 from mistral import expressions
+from mistral.lang import types
+from mistral.lang.v2 import base
+from mistral.lang.v2 import policies
 from mistral import utils
-from mistral.workbook import types
-from mistral.workbook.v2 import base
-from mistral.workbook.v2 import policies
 
 _expr_ptrns = [expressions.patterns[name] for name in expressions.patterns]
 WITH_ITEMS_PTRN = re.compile(
diff --git a/mistral/workbook/v2/workbook.py b/mistral/lang/v2/workbook.py
similarity index 94%
rename from mistral/workbook/v2/workbook.py
rename to mistral/lang/v2/workbook.py
index 2f5d963f1..83d8c0fe5 100644
--- a/mistral/workbook/v2/workbook.py
+++ b/mistral/lang/v2/workbook.py
@@ -13,9 +13,9 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-from mistral.workbook.v2 import actions as act
-from mistral.workbook.v2 import base
-from mistral.workbook.v2 import workflows as wf
+from mistral.lang.v2 import actions as act
+from mistral.lang.v2 import base
+from mistral.lang.v2 import workflows as wf
 
 # We want to match any single word that isn't exactly "version"
 NON_VERSION_WORD_REGEX = "^(?!version$)[\w-]+$"
diff --git a/mistral/workbook/v2/workflows.py b/mistral/lang/v2/workflows.py
similarity index 98%
rename from mistral/workbook/v2/workflows.py
rename to mistral/lang/v2/workflows.py
index e2337b352..44031fcc6 100644
--- a/mistral/workbook/v2/workflows.py
+++ b/mistral/lang/v2/workflows.py
@@ -18,11 +18,11 @@ import six
 import threading
 
 from mistral import exceptions as exc
+from mistral.lang import types
+from mistral.lang.v2 import base
+from mistral.lang.v2 import task_defaults
+from mistral.lang.v2 import tasks
 from mistral import utils
-from mistral.workbook import types
-from mistral.workbook.v2 import base
-from mistral.workbook.v2 import task_defaults
-from mistral.workbook.v2 import tasks
 
 
 class WorkflowSpec(base.BaseSpec):
diff --git a/mistral/services/actions.py b/mistral/services/actions.py
index e9f1574d8..118f1bb31 100644
--- a/mistral/services/actions.py
+++ b/mistral/services/actions.py
@@ -16,7 +16,7 @@ import json
 
 from mistral.db.v2 import api as db_api
 from mistral import exceptions as exc
-from mistral.workbook import parser as spec_parser
+from mistral.lang import parser as spec_parser
 
 
 def create_actions(definition, scope='private'):
diff --git a/mistral/services/triggers.py b/mistral/services/triggers.py
index 19ec8a94c..8c616f398 100644
--- a/mistral/services/triggers.py
+++ b/mistral/services/triggers.py
@@ -21,8 +21,8 @@ from mistral.db.v2 import api as db_api
 from mistral.engine.rpc_backend import rpc
 from mistral.engine import utils as eng_utils
 from mistral import exceptions as exc
+from mistral.lang import parser
 from mistral.services import security
-from mistral.workbook import parser
 
 
 def get_next_execution_time(pattern, start_time):
diff --git a/mistral/services/workbooks.py b/mistral/services/workbooks.py
index 848d28df6..b1bb5ab76 100644
--- a/mistral/services/workbooks.py
+++ b/mistral/services/workbooks.py
@@ -13,8 +13,8 @@
 #    limitations under the License.
 
 from mistral.db.v2 import api as db_api_v2
+from mistral.lang import parser as spec_parser
 from mistral.services import actions
-from mistral.workbook import parser as spec_parser
 
 
 def create_workbook_v2(definition, scope='private'):
diff --git a/mistral/services/workflows.py b/mistral/services/workflows.py
index ebfed895f..53b9c2c8d 100644
--- a/mistral/services/workflows.py
+++ b/mistral/services/workflows.py
@@ -14,8 +14,8 @@
 
 from mistral.db.v2 import api as db_api
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral import utils
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import data_flow
 from mistral.workflow import states
 
diff --git a/mistral/tests/unit/base.py b/mistral/tests/unit/base.py
index a94a666c4..87ff4f342 100644
--- a/mistral/tests/unit/base.py
+++ b/mistral/tests/unit/base.py
@@ -29,12 +29,12 @@ from mistral import context as auth_context
 from mistral.db.sqlalchemy import base as db_sa_base
 from mistral.db.sqlalchemy import sqlite_lock
 from mistral.db.v2 import api as db_api
+from mistral.lang import parser as spec_parser
 from mistral.services import action_manager
 from mistral.services import security
 from mistral.tests.unit import config as test_config
 from mistral.utils import inspect_utils as i_utils
 from mistral import version
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import lookup_utils
 
 RESOURCES_PATH = 'tests/resources/'
diff --git a/mistral/tests/unit/engine/test_policies.py b/mistral/tests/unit/engine/test_policies.py
index 00db9e273..643e69e85 100644
--- a/mistral/tests/unit/engine/test_policies.py
+++ b/mistral/tests/unit/engine/test_policies.py
@@ -21,10 +21,10 @@ from mistral.db.v2 import api as db_api
 from mistral.db.v2.sqlalchemy import models
 from mistral.engine import policies
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral.services import workbooks as wb_service
 from mistral.services import workflows as wf_service
 from mistral.tests.unit.engine import base
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import states
 
 
diff --git a/mistral/tests/unit/engine/test_workflow_resume.py b/mistral/tests/unit/engine/test_workflow_resume.py
index 4b1e11db5..0cb4c32ae 100644
--- a/mistral/tests/unit/engine/test_workflow_resume.py
+++ b/mistral/tests/unit/engine/test_workflow_resume.py
@@ -17,9 +17,9 @@ from oslo_config import cfg
 
 from mistral.db.v2 import api as db_api
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral.services import workbooks as wb_service
 from mistral.tests.unit.engine import base
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import data_flow
 from mistral.workflow import states
 from mistral.workflow import utils
diff --git a/mistral/workbook/__init__.py b/mistral/tests/unit/lang/__init__.py
similarity index 100%
rename from mistral/workbook/__init__.py
rename to mistral/tests/unit/lang/__init__.py
diff --git a/mistral/tests/unit/workbook/test_spec_caching.py b/mistral/tests/unit/lang/test_spec_caching.py
similarity index 99%
rename from mistral/tests/unit/workbook/test_spec_caching.py
rename to mistral/tests/unit/lang/test_spec_caching.py
index 4ffaa1eb1..6c83accd7 100644
--- a/mistral/tests/unit/workbook/test_spec_caching.py
+++ b/mistral/tests/unit/lang/test_spec_caching.py
@@ -13,10 +13,10 @@
 #    limitations under the License.
 
 from mistral.db.v2 import api as db_api
+from mistral.lang import parser as spec_parser
 from mistral.services import workbooks as wb_service
 from mistral.services import workflows as wf_service
 from mistral.tests.unit import base
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import states
 
 
diff --git a/mistral/workbook/v2/__init__.py b/mistral/tests/unit/lang/v2/__init__.py
similarity index 100%
rename from mistral/workbook/v2/__init__.py
rename to mistral/tests/unit/lang/v2/__init__.py
diff --git a/mistral/tests/unit/workbook/v2/base.py b/mistral/tests/unit/lang/v2/base.py
similarity index 98%
rename from mistral/tests/unit/workbook/v2/base.py
rename to mistral/tests/unit/lang/v2/base.py
index 6c62208a0..0ff0b17f5 100644
--- a/mistral/tests/unit/workbook/v2/base.py
+++ b/mistral/tests/unit/lang/v2/base.py
@@ -17,9 +17,9 @@ import copy
 import yaml
 
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral.tests.unit import base
 from mistral import utils
-from mistral.workbook import parser as spec_parser
 
 
 class WorkflowSpecValidationTestCase(base.BaseTest):
diff --git a/mistral/tests/unit/workbook/v2/test_actions.py b/mistral/tests/unit/lang/v2/test_actions.py
similarity index 98%
rename from mistral/tests/unit/workbook/v2/test_actions.py
rename to mistral/tests/unit/lang/v2/test_actions.py
index d599a86d7..2de690798 100644
--- a/mistral/tests/unit/workbook/v2/test_actions.py
+++ b/mistral/tests/unit/lang/v2/test_actions.py
@@ -15,7 +15,7 @@
 
 import copy
 
-from mistral.tests.unit.workbook.v2 import base
+from mistral.tests.unit.lang.v2 import base
 from mistral import utils
 
 
diff --git a/mistral/tests/unit/workbook/v2/test_tasks.py b/mistral/tests/unit/lang/v2/test_tasks.py
similarity index 99%
rename from mistral/tests/unit/workbook/v2/test_tasks.py
rename to mistral/tests/unit/lang/v2/test_tasks.py
index e04d89edd..b2b010c5d 100644
--- a/mistral/tests/unit/workbook/v2/test_tasks.py
+++ b/mistral/tests/unit/lang/v2/test_tasks.py
@@ -14,9 +14,9 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-from mistral.tests.unit.workbook.v2 import base as v2_base
+from mistral.lang.v2 import workflows
+from mistral.tests.unit.lang.v2 import base as v2_base
 from mistral import utils
-from mistral.workbook.v2 import workflows
 
 
 class TaskSpecValidation(v2_base.WorkflowSpecValidationTestCase):
diff --git a/mistral/tests/unit/workbook/v2/test_workbook.py b/mistral/tests/unit/lang/v2/test_workbook.py
similarity index 99%
rename from mistral/tests/unit/workbook/v2/test_workbook.py
rename to mistral/tests/unit/lang/v2/test_workbook.py
index 62019eb5c..97c5738a4 100644
--- a/mistral/tests/unit/workbook/v2/test_workbook.py
+++ b/mistral/tests/unit/lang/v2/test_workbook.py
@@ -19,8 +19,8 @@ import re
 import yaml
 
 from mistral import exceptions as exc
-from mistral.tests.unit.workbook.v2 import base
-from mistral.workbook.v2 import workbook
+from mistral.lang.v2 import workbook
+from mistral.tests.unit.lang.v2 import base
 
 
 class WorkbookSpecValidation(base.WorkbookSpecValidationTestCase):
diff --git a/mistral/tests/unit/workbook/v2/test_workflows.py b/mistral/tests/unit/lang/v2/test_workflows.py
similarity index 99%
rename from mistral/tests/unit/workbook/v2/test_workflows.py
rename to mistral/tests/unit/lang/v2/test_workflows.py
index 849f1a66d..4613520d2 100644
--- a/mistral/tests/unit/workbook/v2/test_workflows.py
+++ b/mistral/tests/unit/lang/v2/test_workflows.py
@@ -18,7 +18,7 @@ import copy
 import yaml
 
 from mistral import exceptions as exc
-from mistral.tests.unit.workbook.v2 import base
+from mistral.tests.unit.lang.v2 import base
 from mistral import utils
 
 
diff --git a/mistral/tests/unit/services/test_action_service.py b/mistral/tests/unit/services/test_action_service.py
index bd7db568a..ffd68f762 100644
--- a/mistral/tests/unit/services/test_action_service.py
+++ b/mistral/tests/unit/services/test_action_service.py
@@ -15,10 +15,10 @@
 from oslo_config import cfg
 
 from mistral.db.v2 import api as db_api
+from mistral.lang import parser as spec_parser
 from mistral.services import actions as action_service
 from mistral.tests.unit import base
 from mistral import utils
-from mistral.workbook import parser as spec_parser
 
 
 # Use the set_default method to set value otherwise in certain test cases
diff --git a/mistral/tests/unit/services/test_workbook_service.py b/mistral/tests/unit/services/test_workbook_service.py
index aa2059bd5..f86821773 100644
--- a/mistral/tests/unit/services/test_workbook_service.py
+++ b/mistral/tests/unit/services/test_workbook_service.py
@@ -15,9 +15,9 @@
 from oslo_config import cfg
 
 from mistral.db.v2 import api as db_api
+from mistral.lang import parser as spec_parser
 from mistral.services import workbooks as wb_service
 from mistral.tests.unit import base
-from mistral.workbook import parser as spec_parser
 
 
 # Use the set_default method to set value otherwise in certain test cases
diff --git a/mistral/tests/unit/services/test_workflow_service.py b/mistral/tests/unit/services/test_workflow_service.py
index bcdf212df..cd8a9dff6 100644
--- a/mistral/tests/unit/services/test_workflow_service.py
+++ b/mistral/tests/unit/services/test_workflow_service.py
@@ -19,10 +19,10 @@ from oslo_config import cfg
 
 from mistral.db.v2.sqlalchemy import api as db_api
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral.services import workflows as wf_service
 from mistral.tests.unit import base
 from mistral import utils
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import states
 
 
diff --git a/mistral/tests/unit/workflow/test_direct_workflow.py b/mistral/tests/unit/workflow/test_direct_workflow.py
index 00f037b76..f78f8b219 100644
--- a/mistral/tests/unit/workflow/test_direct_workflow.py
+++ b/mistral/tests/unit/workflow/test_direct_workflow.py
@@ -17,9 +17,9 @@ import mock
 from mistral.db.v2 import api as db_api
 from mistral.db.v2.sqlalchemy import models
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral.services import workflows as wf_service
 from mistral.tests.unit import base
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import direct_workflow as d_wf
 from mistral.workflow import states
 
diff --git a/mistral/tests/unit/workflow/test_reverse_workflow.py b/mistral/tests/unit/workflow/test_reverse_workflow.py
index 84f0bff48..70311dd99 100644
--- a/mistral/tests/unit/workflow/test_reverse_workflow.py
+++ b/mistral/tests/unit/workflow/test_reverse_workflow.py
@@ -15,9 +15,9 @@
 from mistral.db.v2 import api as db_api
 from mistral.db.v2.sqlalchemy import models
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral.services import workbooks as wb_service
 from mistral.tests.unit import base
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import reverse_workflow as reverse_wf
 from mistral.workflow import states
 
diff --git a/mistral/tests/unit/workflow/test_workflow_base.py b/mistral/tests/unit/workflow/test_workflow_base.py
index b2b7d2ead..fb62b5ef4 100644
--- a/mistral/tests/unit/workflow/test_workflow_base.py
+++ b/mistral/tests/unit/workflow/test_workflow_base.py
@@ -13,8 +13,8 @@
 #    limitations under the License.
 
 
+from mistral.lang import parser as spec_parser
 from mistral.tests.unit import base
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import base as wf_base
 from mistral.workflow import direct_workflow as direct_wf
 from mistral.workflow import reverse_workflow as reverse_wf
diff --git a/mistral/workflow/base.py b/mistral/workflow/base.py
index cc7d5dd04..f74b72332 100644
--- a/mistral/workflow/base.py
+++ b/mistral/workflow/base.py
@@ -21,8 +21,8 @@ from oslo_log import log as logging
 from osprofiler import profiler
 
 from mistral import exceptions as exc
+from mistral.lang import parser as spec_parser
 from mistral import utils as u
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import commands
 from mistral.workflow import data_flow
 from mistral.workflow import lookup_utils
diff --git a/mistral/workflow/commands.py b/mistral/workflow/commands.py
index 8ef928601..45ee50465 100644
--- a/mistral/workflow/commands.py
+++ b/mistral/workflow/commands.py
@@ -13,8 +13,8 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
-from mistral.workbook import parser as spec_parser
-from mistral.workbook.v2 import tasks
+from mistral.lang import parser as spec_parser
+from mistral.lang.v2 import tasks
 from mistral.workflow import states
 
 
diff --git a/mistral/workflow/data_flow.py b/mistral/workflow/data_flow.py
index ab8801b62..420c0332e 100644
--- a/mistral/workflow/data_flow.py
+++ b/mistral/workflow/data_flow.py
@@ -22,9 +22,9 @@ from mistral import context as auth_ctx
 from mistral.db.v2.sqlalchemy import models
 from mistral import exceptions as exc
 from mistral import expressions as expr
+from mistral.lang import parser as spec_parser
 from mistral import utils
 from mistral.utils import inspect_utils
-from mistral.workbook import parser as spec_parser
 from mistral.workflow import states
 
 LOG = logging.getLogger(__name__)