diff --git a/reana_commons/serial.py b/reana_commons/serial.py
new file mode 100644
index 00000000..6fa9b78b
--- /dev/null
+++ b/reana_commons/serial.py
@@ -0,0 +1,109 @@
+# -*- coding: utf-8 -*-
+#
+# This file is part of REANA.
+# Copyright (C) 2018 CERN.
+#
+# REANA is free software; you can redistribute it and/or modify it under the
+# terms of the GNU General Public License as published by the Free Software
+# Foundation; either version 2 of the License, or (at your option) any later
+# version.
+#
+# REANA is distributed in the hope that it will be useful, but WITHOUT ANY
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+# A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# REANA; if not, write to the Free Software Foundation, Inc., 59 Temple Place,
+# Suite 330, Boston, MA 02111-1307, USA.
+#
+# In applying this license, CERN does not waive the privileges and immunities
+# granted to it by virtue of its status as an Intergovernmental Organization or
+# submit itself to any jurisdiction.
+"""REANA Workflow Engine Serial implementation utils."""
+
+
+import json
+from copy import deepcopy
+from string import Template
+
+from jsonschema import ValidationError, validate
+
+serial_workflow_schema = {
+    "$schema": "http://json-schema.org/draft-06/schema#",
+    "id": "serial_workflow_specification",
+    "type": "object",
+    "required": ["steps"],
+    "properties": {
+        "steps": {
+            "$id": "#/properties/steps",
+            "type": "array",
+            "minItems": 1,
+            "items": {
+                "$id": "#/properties/steps/items",
+                "type": "object",
+                "required": [
+                    "commands"
+                ],
+                "properties": {
+                    "environment": {
+                        "$id": "#/properties/steps/properties/environment",
+                        "type": "string",
+                    },
+                    "commands": {
+                        "$id": "#/properties/steps/properties/commands",
+                        "type": "array",
+                        "minItems": 1,
+                        "items": {
+                            "$id": "#/properties/steps/items/properties/"
+                                "commands/items",
+                            "type": "string"
+                        },
+                    }
+                }
+            }
+        }
+    }
+}
+
+
+def serial_load(workflow_file, specification, parameters):
+    """Validate and return a expanded REANA Serial workflow specification.
+
+    :param workflow_file: A specification file compliant with
+        REANA Serial workflow specification.
+    :returns: A dictionary which represents the valid Serial workflow with all
+        parameters expanded.
+    """
+    if not specification:
+        with open(workflow_file, 'r') as f:
+            specification = json.loads(f.read())
+
+    expanded_specification = _expand_parameters(specification, parameters)
+
+    validate(specification, serial_workflow_schema)
+
+    return expanded_specification
+
+
+def _expand_parameters(specification, parameters):
+    """Expand parameters inside comands for Serial workflow specifications.
+
+    :param specification: Full valid Serial workflow specification.
+    :param parameters: Parameters to be extended on a Serial specification.
+    :returns: Specification with expanded parameters (all $varname and
+        ${varname} will be expanded with their value). Otherwise an error
+        will be thrown if the parameters can not be expanded.
+    :raises: jsonschema.ValidationError
+    """
+    expanded_specification = deepcopy(specification)
+
+    try:
+        for step in expanded_specification['steps']:
+            for command in step['commands']:
+                command = Template(command).substitute(parameters)
+
+        return expanded_specification
+    except KeyError as e:
+        raise ValidationError('Workflow parameter(s) could not '
+                              'be expanded. Please take a look '
+                              'to {params}'.format(params=str(e)))
diff --git a/setup.py b/setup.py
index 8728d886..64fb114a 100755
--- a/setup.py
+++ b/setup.py
@@ -66,6 +66,7 @@
     'checksumdir>=1.1.4',
     'click>=6.7',
     'fs>=0.5.4',
+    'jsonschema>=2.6.0',
     'pika>=0.12.0',
 ]