diff --git a/.gitignore b/.gitignore
index 9431eae1..7b72bbae 100644
--- a/.gitignore
+++ b/.gitignore
@@ -52,3 +52,4 @@ docs/build
 .spyderproject
 .spyderworkspace
 .spyproject
+.vscode
\ No newline at end of file
diff --git a/.travis.yml b/.travis.yml
index 3a82f2d6..d1fff75f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -10,9 +10,9 @@ branches:
 
 matrix:
   include:
-    - env: PYTHON=3.5 CONDA_PY=35 QT_VERSION=5
     - env: PYTHON=3.6 CONDA_PY=36 QT_VERSION=5
     - env: PYTHON=3.7 CONDA_PY=37 QT_VERSION=5
+    - env: PYTHON=3.8 CONDA_PY=38 QT_VERSION=5
 
 before_install:
 
@@ -25,6 +25,7 @@ before_install:
   # Setup environment
   - travis_retry conda update --yes conda
   - conda config --set always_yes yes
+  - conda config --append channels conda-forge
   - conda config --append channels exopy
   - conda install conda-build anaconda-client -q
   - conda info -a
@@ -40,7 +41,7 @@ before_install:
   - export CONDA_BLD_PATH=$(pwd)
 
   # Install exopy dependencies
-  - $CONDA_INSTALL pyqt=$QT_VERSION numpy configobj watchdog enaml>=0.10.2 qtawesome pyvisa
+  - $CONDA_INSTALL pyqt=$QT_VERSION numpy configobj watchdog qtawesome pyvisa enaml>=0.11.0
 
   # Intall test tools
   - $CONDA_INSTALL pytest
diff --git a/docs/source/dev_guide/atom_enaml.rst b/docs/source/dev_guide/atom_enaml.rst
index 1cc07547..bb72c89b 100644
--- a/docs/source/dev_guide/atom_enaml.rst
+++ b/docs/source/dev_guide/atom_enaml.rst
@@ -15,10 +15,6 @@ duck-typing but tends to make the code easier to read. Note also that metadata
 can be added to a member using the :py:meth:tag method. Metadata are
 extensively used in Exopy.
 
-.. note::
-
-    For clarity sake and Python2/3 compatibility, Unicode should be used
-    instead of Str.
 
 Enaml
 -----
diff --git a/docs/source/dev_guide/tasks.rst b/docs/source/dev_guide/tasks.rst
index 5423980b..0921e159 100644
--- a/docs/source/dev_guide/tasks.rst
+++ b/docs/source/dev_guide/tasks.rst
@@ -61,7 +61,7 @@ used to identify the part to replace with the value stored in the database).
         my_int = Int(1).tag(pref=True)  # Integer with a default value of 1
 
         #: my_text description
-        my_text = Unicode().tag(pref=True)
+        my_text = Str().tag(pref=True)
 
 Tasks use a common database (which is nothing else that a kind of smart
 dictionary) to exchange data. If a task needs to write a value in the database
@@ -123,12 +123,12 @@ simply need to tag the concerned member with 'fmt' (formatting only) or 'feval'
         """MyTask description.
 
         """
-        value1 = Unicode().tag(feval=v.Feval(types=numbers.Real,
+        value1 = Str().tag(feval=v.Feval(types=numbers.Real,
                                              warn=True))
 
-        value2 = Unicode().tag(feval=v.SkipEmpty())
+        value2 = Str().tag(feval=v.SkipEmpty())
 
-        value3 = Unicode().tag(feval=v.SkipLoop())
+        value3 = Str().tag(feval=v.SkipLoop())
 
 In the above example :
 
@@ -370,7 +370,7 @@ implemented and the handling of the database use the same members.
 
 .. code-block:: python
 
-    from atom.api import Unicode, Int
+    from atom.api import Str, Int
 
     class MyInterface(TaskInterface):
         """MyInterface description.
@@ -382,7 +382,7 @@ implemented and the handling of the database use the same members.
         my_int = Int(1).tag(pref=True)  # Integer with a default value of 1
 
         #: my_text description
-        my_text = Unicode().tag(pref=True)
+        my_text = Str().tag(pref=True)
 
         database_entries = set_default({'val': 1})
 
diff --git a/exopy/app/app_extensions.py b/exopy/app/app_extensions.py
index 3c537fde..bf5ae2c0 100644
--- a/exopy/app/app_extensions.py
+++ b/exopy/app/app_extensions.py
@@ -9,7 +9,7 @@
 """App plugin extensions declarations.
 
 """
-from atom.api import Unicode, Int
+from atom.api import Str, Int
 from enaml.core.api import Declarative, d_, d_func
 
 
@@ -22,7 +22,7 @@ class AppStartup(Declarative):
 
     """
     #: The globally unique identifier for the start-up.
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: The priority determine the order in which AppStartup are called. The
     #: **lowest** this number the sooner the object will be called. Two
@@ -64,7 +64,7 @@ class AppClosing(Declarative):
 
     """
     #: The globally unique identifier for the closing.
-    id = d_(Unicode())
+    id = d_(Str())
 
     @d_func
     def validate(self, window, event):
@@ -107,7 +107,7 @@ class AppClosed(Declarative):
 
     """
     #: The globally unique identifier for the closing.
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: The priority determine the order in which AppClosed are called. The
     #: **lowest** this number the sooner the object will be called. Two
diff --git a/exopy/app/dependencies/dependencies.py b/exopy/app/dependencies/dependencies.py
index e8efaf67..cf651831 100644
--- a/exopy/app/dependencies/dependencies.py
+++ b/exopy/app/dependencies/dependencies.py
@@ -16,7 +16,7 @@
 also drivers classes and intsrument profiles (runtime)
 
 """
-from atom.api import (Unicode)
+from atom.api import (Str)
 from enaml.core.api import Declarative, d_, d_func
 
 
@@ -31,7 +31,7 @@ class BuildDependency(Declarative):
     """
     #: Unique id for this extension. Should match the dep_type attribute value
     #: of the object it is meant for.
-    id = d_(Unicode())
+    id = d_(Str())
 
     @d_func
     def analyse(self, workbench, obj, getter, dependencies, errors):
@@ -125,11 +125,11 @@ class RuntimeDependencyAnalyser(Declarative):
 
     """
     #: Unique id for this extension.
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: Id of the collector that should be used to collect the dependencies
     #: discovered during analysis.
-    collector_id = d_(Unicode())
+    collector_id = d_(Str())
 
     @d_func
     def analyse(self, workbench, obj, dependencies, errors):
@@ -164,7 +164,7 @@ class RuntimeDependencyCollector(Declarative):
 
     """
     #: Unique id for this extension.
-    id = d_(Unicode())
+    id = d_(Str())
 
     @d_func
     def validate(self, workbench, dependencies, errors):
diff --git a/exopy/app/errors/errors.py b/exopy/app/errors/errors.py
index d24785a4..9d45a1a3 100644
--- a/exopy/app/errors/errors.py
+++ b/exopy/app/errors/errors.py
@@ -9,7 +9,7 @@
 """Declarations for the extensions to the error plugin.
 
 """
-from atom.api import Unicode
+from atom.api import Str
 from enaml.core.api import Declarative, d_, d_func
 
 
@@ -18,11 +18,11 @@ class ErrorHandler(Declarative):
 
     """
     #: Id of the error. When signaling errors it will referred to as the kind.
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: Short description of what this handler can do. The keyword for the
     #: handle method should be specified.
-    description = d_(Unicode())
+    description = d_(Str())
 
     @d_func
     def handle(self, workbench, infos):
diff --git a/exopy/app/icons/icon_theme.py b/exopy/app/icons/icon_theme.py
index 819a9297..9612daf8 100644
--- a/exopy/app/icons/icon_theme.py
+++ b/exopy/app/icons/icon_theme.py
@@ -9,7 +9,7 @@
 """Extension objects to the icon plugin.
 
 """
-from atom.api import Unicode, Dict, List
+from atom.api import Str, Dict, List
 from enaml.core.api import Declarative, d_, d_func
 
 
@@ -25,7 +25,7 @@ class IconTheme(Declarative):
 
     """
     #: Unique id of the icon theme.
-    id = d_(Unicode())
+    id = d_(Str())
 
     @d_func
     def get_icon(self, manager, icon_id):
@@ -77,10 +77,10 @@ class IconThemeExtension(Declarative):
 
     """
     #: Unicsue id of the extension.
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: Id of the icon theme to which to contribute the children Icon objects.
-    theme = d_(Unicode())
+    theme = d_(Str())
 
     def icons(self):
         """List the associated icons.
@@ -103,7 +103,7 @@ class Icon(Declarative):
     """
     #: Unique id describing the icon. It should provide a clear description
     #: of the icon purpose.
-    id = d_(Unicode())
+    id = d_(Str())
 
     @d_func
     def get_icon(self, manager, theme):
diff --git a/exopy/app/icons/plugin.py b/exopy/app/icons/plugin.py
index c6ec105e..fc6867bd 100644
--- a/exopy/app/icons/plugin.py
+++ b/exopy/app/icons/plugin.py
@@ -11,7 +11,7 @@
 """
 import logging
 
-from atom.api import List, Typed, Unicode
+from atom.api import List, Typed, Str
 
 from .icon_theme import IconTheme, IconThemeExtension
 from ...utils.traceback import format_exc
@@ -29,11 +29,11 @@ class IconManagerPlugin(HasPreferencesPlugin):
 
     """
     #: Id of the currently selected icon theme
-    current_theme = Unicode('exopy.FontAwesome').tag(pref=True)
+    current_theme = Str('exopy.FontAwesome').tag(pref=True)
 
     #: Id of the icon theme to use as fallback if a theme fail to provide an
     #: icon.
-    fallback_theme = Unicode('exopy.FontAwesome').tag(pref=True)
+    fallback_theme = Str('exopy.FontAwesome').tag(pref=True)
 
     #: Registered icon themes ids
     icon_themes = List()
diff --git a/exopy/app/log/plugin.py b/exopy/app/log/plugin.py
index c41c98fa..8b8e63d9 100644
--- a/exopy/app/log/plugin.py
+++ b/exopy/app/log/plugin.py
@@ -12,7 +12,7 @@
 import os
 import logging
 
-from atom.api import Unicode, Dict, List, Tuple, Typed
+from atom.api import Str, Dict, List, Tuple, Typed
 from enaml.workbench.api import Plugin
 
 from .tools import (LogModel, GuiHandler, DayRotatingTimeHandler)
@@ -30,10 +30,10 @@ class LogPlugin(Plugin):
 
     """
     #: List of installed handlers.
-    handler_ids = List(Unicode())
+    handler_ids = List(Str())
 
     #: List of installed filters.
-    filter_ids = List(Unicode())
+    filter_ids = List(Str())
 
     #: Model which can be used to display the log in the GUI. It is associated
     #: to a handler attached to the root logger.
@@ -197,7 +197,7 @@ def set_formatter(self, handler_id, formatter):
     # ---- Private API --------------------------------------------------------
 
     # Mapping between handler ids and handler, logger name pairs.
-    _handlers = Dict(Unicode(), Tuple())
+    _handlers = Dict(Str(), Tuple())
 
     # Mapping between filter_id and filter, handler_id pairs.
-    _filters = Dict(Unicode(), Tuple())
+    _filters = Dict(Str(), Tuple())
diff --git a/exopy/app/log/tools.py b/exopy/app/log/tools.py
index b49ed137..48b18f0a 100644
--- a/exopy/app/log/tools.py
+++ b/exopy/app/log/tools.py
@@ -32,7 +32,7 @@
 from logging.handlers import TimedRotatingFileHandler
 from threading import Thread
 from enaml.application import deferred_call
-from atom.api import Atom, Unicode, Int
+from atom.api import Atom, Str, Int
 import codecs
 
 
@@ -199,7 +199,7 @@ class LogModel(Atom):
     """
     #: Text representing all the messages sent by the handler.
     #: Should not be altered by user code.
-    text = Unicode()
+    text = Str()
 
     #: Maximum number of lines.
     buff_size = Int(1000)
diff --git a/exopy/app/preferences/plugin.py b/exopy/app/preferences/plugin.py
index bc4377d1..7778bf23 100644
--- a/exopy/app/preferences/plugin.py
+++ b/exopy/app/preferences/plugin.py
@@ -10,7 +10,7 @@
 
 """
 import os
-from atom.api import Unicode, Typed, Dict
+from atom.api import Str, Typed, Dict
 from enaml.workbench.api import Plugin
 from configobj import ConfigObj
 from functools import partial
@@ -29,10 +29,10 @@ class PrefPlugin(Plugin):
     """
     #: Folder used by the application to store informations such as preferences
     #: log files, ...
-    app_directory = Unicode()
+    app_directory = Str()
 
     #: Path of the last location visited using a dialog.
-    last_directory = Unicode()
+    last_directory = Str()
 
     def start(self):
         """Start the plugin, locate app folder and load default preferences.
diff --git a/exopy/app/preferences/preferences.py b/exopy/app/preferences/preferences.py
index 50e1d8c9..db5c7940 100644
--- a/exopy/app/preferences/preferences.py
+++ b/exopy/app/preferences/preferences.py
@@ -9,7 +9,7 @@
 """Declarative class for defining hnadling of preferences.
 
 """
-from atom.api import List, Unicode
+from atom.api import List, Str
 from enaml.core.api import Declarative, d_, d_func
 
 
@@ -22,11 +22,11 @@ class Preferences(Declarative):
     """
     #: Name of the method of the plugin contributing this extension to call
     #: when the preference plugin need to save the preferences.
-    saving_method = d_(Unicode('preferences_from_members'))
+    saving_method = d_(Str('preferences_from_members'))
 
     #: Name of the method of the plugin contributing this extension to call
     #: when the preference plugin need to load preferences.
-    loading_method = d_(Unicode('update_members_from_preferences'))
+    loading_method = d_(Str('update_members_from_preferences'))
 
     #: The list of plugin members whose values should be observed and whose
     #: update should cause and automatic update of the preferences.
diff --git a/exopy/app/states/state.py b/exopy/app/states/state.py
index 98ed580f..fc88449b 100644
--- a/exopy/app/states/state.py
+++ b/exopy/app/states/state.py
@@ -9,7 +9,7 @@
 """State plugin extension declaration.
 
 """
-from atom.api import (List, Unicode)
+from atom.api import (List, Str)
 from enaml.core.api import Declarative, d_
 
 
@@ -21,11 +21,11 @@ class State(Declarative):
 
     """
     #: The globally unique identifier for the state
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: An optional description of what the state provides.
-    description = d_(Unicode())
+    description = d_(Str())
 
     #: The list of plugin members whose values should be reflected in the
     #: state object
-    sync_members = d_(List(Unicode()))
+    sync_members = d_(List(Str()))
diff --git a/exopy/instruments/connections/base_connection.py b/exopy/instruments/connections/base_connection.py
index 91a91bd3..6bbce4c1 100644
--- a/exopy/instruments/connections/base_connection.py
+++ b/exopy/instruments/connections/base_connection.py
@@ -14,7 +14,7 @@
 starter used to instantiate the driver.
 
 """
-from atom.api import Unicode, ForwardTyped, Bool
+from atom.api import Str, ForwardTyped, Bool
 from enaml.core.api import d_, Declarative, d_func
 from enaml.widgets.api import GroupBox
 
@@ -45,10 +45,10 @@ class Connection(Declarative):
 
     """
     #: Unique name used to identify the connection.
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: Connection description.
-    description = d_(Unicode())
+    description = d_(Str())
 
     @d_func
     def new(self, workbench, defaults, read_only):
diff --git a/exopy/instruments/drivers/driver_decl.py b/exopy/instruments/drivers/driver_decl.py
index dd9a56a8..1ba7ca1b 100644
--- a/exopy/instruments/drivers/driver_decl.py
+++ b/exopy/instruments/drivers/driver_decl.py
@@ -9,7 +9,7 @@
 """Declarator for registering drivers.
 
 """
-from atom.api import Unicode, Dict, Property, Enum
+from atom.api import Str, Dict, Property, Enum
 from enaml.core.api import d_
 
 from ...utils.traceback import format_exc
@@ -25,24 +25,24 @@ class Driver(Declarator):
     #: name preceded by ':'.
     #: TODO complete : ex: exopy_hqc_legacy.instruments.
     #: The path of any parent Drivers object will be prepended to it.
-    driver = d_(Unicode())
+    driver = d_(Str())
 
     #: Name identifying the system the driver is built on top of (lantz, hqc,
     #: slave, etc ...). Allow to handle properly multiple drivers declared in
     #: a single extension package for the same instrument.
-    architecture = d_(Unicode())
+    architecture = d_(Str())
 
     #: Name of the instrument manufacturer. Can be inferred from parent
     #: Drivers.
-    manufacturer = d_(Unicode())
+    manufacturer = d_(Str())
 
     #: Serie this instrument is part of. This is optional as it does not always
     #: make sense to be specified but in some cases it can help finding a
     #: a driver. Can be inferred from parent Drivers.
-    serie = d_(Unicode())
+    serie = d_(Str())
 
     #: Model of the instrument this driver has been written for.
-    model = d_(Unicode())
+    model = d_(Str())
 
     #: Kind of the instrument, to ease instrument look up. If no kind match,
     #: leave 'Other' as the kind. Can be inferred from parent
@@ -51,7 +51,7 @@ class Driver(Declarator):
 
     #: Starter to use when initializing/finialzing this driver.
     #: Can be inferred from parent Drivers.
-    starter = d_(Unicode())
+    starter = d_(Str())
 
     #: Supported connections and default values for some parameters. The
     #: admissible values for a given kind can be determined by looking at the
@@ -264,19 +264,19 @@ class Drivers(GroupDeclarator):
     """
     #: Name identifying the system the driver is built on top of for the
     #: declared children.
-    architecture = d_(Unicode())
+    architecture = d_(Str())
 
     #: Instrument manufacturer of the declared children.
-    manufacturer = d_(Unicode())
+    manufacturer = d_(Str())
 
     #: Serie of the declared children.
-    serie = d_(Unicode())
+    serie = d_(Str())
 
     #: Kind of the declared children.
     kind = d_(Enum(None, *INSTRUMENT_KINDS))
 
     #: Starter to use for the declared children.
-    starter = d_(Unicode())
+    starter = d_(Str())
 
     #: Supported connections of the declared children.
     connections = d_(Dict())
diff --git a/exopy/instruments/infos.py b/exopy/instruments/infos.py
index 9fc28e4a..3c68a76d 100644
--- a/exopy/instruments/infos.py
+++ b/exopy/instruments/infos.py
@@ -14,7 +14,7 @@
 from operator import attrgetter
 
 from configobj import ConfigObj
-from atom.api import (Atom, Unicode, Dict, Callable, List, Property, Typed,
+from atom.api import (Atom, Str, Dict, Callable, List, Property, Typed,
                       Bool, Enum, Value)
 
 from ..utils.mapping_utils import recursive_update
@@ -29,7 +29,7 @@ class DriverInfos(Atom):
 
     """
     #: Id of the driver built on the class name and the top-level package
-    id = Unicode()
+    id = Str()
 
     #: Actual class to use as driver.
     cls = Callable()
@@ -38,7 +38,7 @@ class DriverInfos(Atom):
     infos = Dict()
 
     #: Starter id
-    starter = Unicode()
+    starter = Str()
 
     #: Connection information.
     connections = Dict()
@@ -101,13 +101,13 @@ class InstrumentModelInfos(Atom):
 
     """
     #: Instrument manufacturer (this is the real manufacturer not an alias).
-    manufacturer = Unicode()
+    manufacturer = Str()
 
     #: Instrument model.
-    model = Unicode()
+    model = Str()
 
     #: Instrument serie.
-    serie = Unicode()
+    serie = Str()
 
     #: Instrument kind.
     kind = Enum(*INSTRUMENT_KINDS)
@@ -186,7 +186,7 @@ class SeriesInfos(Atom):
 
     """
     #: Name of the serie.
-    name = Unicode()
+    name = Str()
 
     #: List of the instrument models matching the selected kind.
     #: This object should not be manipulated by user code.
@@ -333,7 +333,7 @@ class ManufacturersHolder(Atom):
     use_series = Bool(True)
 
     #: Expose the known instruments only of the matching kind.
-    kind = Unicode('All')
+    kind = Str('All')
 
     def update_manufacturers(self, drivers, removed=False):
         """Update a manufacturer infos and create it if it does not exist yet.
@@ -411,13 +411,13 @@ class ProfileInfos(Atom):
 
     """
     #: Path to the .ini file holding the full infos.
-    path = Unicode()
+    path = Str()
 
     #: Reference to the instrument plugin.
     plugin = Value()
 
     #: Profile id.
-    id = Unicode()
+    id = Str()
 
     #: Supported model
     model = Typed(InstrumentModelInfos)
diff --git a/exopy/instruments/manufacturer_aliases.py b/exopy/instruments/manufacturer_aliases.py
index 7e3fc68a..b7d97016 100644
--- a/exopy/instruments/manufacturer_aliases.py
+++ b/exopy/instruments/manufacturer_aliases.py
@@ -11,7 +11,7 @@
 ex : Keysight : aliases Agilent, HP
 
 """
-from atom.api import Unicode, List
+from atom.api import Str, List
 from enaml.core.api import Declarative, d_
 
 
@@ -20,7 +20,7 @@ class ManufacturerAlias(Declarative):
 
     """
     #: Main name under which the vendor is expected to be known
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: List of aliased names.
     aliases = d_(List())
diff --git a/exopy/instruments/settings/base_settings.py b/exopy/instruments/settings/base_settings.py
index cf004d5e..99edc396 100644
--- a/exopy/instruments/settings/base_settings.py
+++ b/exopy/instruments/settings/base_settings.py
@@ -12,7 +12,7 @@
 if several are available for example.
 
 """
-from atom.api import Unicode, ForwardTyped, Bool
+from atom.api import Str, ForwardTyped, Bool
 from enaml.core.api import d_, Declarative, d_func
 from enaml.widgets.api import GroupBox
 
@@ -23,7 +23,7 @@ class BaseSettings(GroupBox):
     """
     #: Id of this settings (different from the declaration one as multiple
     #: settings of the same type can exist for a single instrument).
-    user_id = d_(Unicode())
+    user_id = d_(Str())
 
     #: Reference to the declaration that created this object.
     declaration = d_(ForwardTyped(lambda: Settings))
@@ -58,10 +58,10 @@ class Settings(Declarative):
 
     """
     #: Unique name used to identify the editor.
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: Connection description.
-    description = d_(Unicode())
+    description = d_(Str())
 
     @d_func
     def new(self, workbench, defaults, read_only):
diff --git a/exopy/instruments/starters/base_starter.py b/exopy/instruments/starters/base_starter.py
index cc395287..854b034d 100644
--- a/exopy/instruments/starters/base_starter.py
+++ b/exopy/instruments/starters/base_starter.py
@@ -9,7 +9,7 @@
 """Tool handling initializind/finalizing a driver.
 
 """
-from atom.api import Atom, Unicode, Typed
+from atom.api import Atom, Str, Typed
 from enaml.core.api import Declarative, d_
 
 
@@ -18,7 +18,7 @@ class BaseStarter(Atom):
 
     """
     #: Id of the starter set by the declaration.
-    id = Unicode()
+    id = Str()
 
     def start(self, driver_cls, connection, settings):
         """Fully initialize a driver and open the communication channel.
@@ -101,10 +101,10 @@ class Starter(Declarative):
     """
     #: Unique id identifying this starter.
     #: The usual format is top_level_package_name.starter_name
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: Description of the starter action.
-    description = d_(Unicode())
+    description = d_(Str())
 
     #: Starter instance to use for managing associate instruments.
     #: Note that the class must be defined in a python file not enaml file
diff --git a/exopy/instruments/user.py b/exopy/instruments/user.py
index b1620518..af927dba 100644
--- a/exopy/instruments/user.py
+++ b/exopy/instruments/user.py
@@ -9,7 +9,7 @@
 """Declaration of plugin susceptible to use instruments
 
 """
-from atom.api import Enum, Unicode
+from atom.api import Enum, Str
 from enaml.core.declarative import Declarative, d_, d_func
 
 
@@ -20,7 +20,7 @@ class InstrUser(Declarative):
     #: Plugin id associated with this use of instrument. This allow the manager
     #: to know what part of the application requested the right to use some
     #: drivers.
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: Is the plugin susceptible to release the profiles it is currently using
     #: if the manager asks it to do so.
diff --git a/exopy/measurement/base_tool.py b/exopy/measurement/base_tool.py
index 05e72e9b..a837ff60 100644
--- a/exopy/measurement/base_tool.py
+++ b/exopy/measurement/base_tool.py
@@ -24,7 +24,7 @@
 """
 import sys
 
-from atom.api import ForwardTyped, Unicode, Bool
+from atom.api import ForwardTyped, Str, Bool
 from enaml.core.api import Declarative, d_, d_func
 
 from ..utils.atom_util import HasPrefAtom
@@ -102,10 +102,10 @@ class BaseToolDeclaration(Declarative):
     """
     #: Unique name used to identify the tool.
     #: The usual format is top_level_package_name.tool_name
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: Description of the tool.
-    description = d_(Unicode())
+    description = d_(Str())
 
     #: Flag indicating whether the tool has an associated parametrisation
     #: widget.
diff --git a/exopy/measurement/editors/base_editor.py b/exopy/measurement/editors/base_editor.py
index cc7b1d78..eb88168a 100644
--- a/exopy/measurement/editors/base_editor.py
+++ b/exopy/measurement/editors/base_editor.py
@@ -9,7 +9,7 @@
 """Base classes for all editors.
 
 """
-from atom.api import Unicode, Typed, Bool, ForwardTyped, Int
+from atom.api import Str, Typed, Bool, ForwardTyped, Int
 from enaml.core.api import Declarative, d_, d_func
 from enaml.widgets.api import Page
 
@@ -80,10 +80,10 @@ class Editor(Declarative):
     """
     #: Unique name used to identify the editor.
     #: The usual format is top_level_package_name.tool_name
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: Editor description.
-    description = d_(Unicode())
+    description = d_(Str())
 
     #: Rank of this editor. Editors are displayed by rank and alphabetical
     #: order
diff --git a/exopy/measurement/engines/base_engine.py b/exopy/measurement/engines/base_engine.py
index 16629611..a74a29cf 100644
--- a/exopy/measurement/engines/base_engine.py
+++ b/exopy/measurement/engines/base_engine.py
@@ -9,7 +9,7 @@
 """Base classes for all engines
 
 """
-from atom.api import (Atom, Unicode, ForwardTyped, Signal, Enum, Bool, Dict,
+from atom.api import (Atom, Str, ForwardTyped, Signal, Enum, Bool, Dict,
                       Value, List)
 from enaml.core.api import Declarative, d_, d_func
 
@@ -22,7 +22,7 @@ class ExecutionInfos(Atom):
 
     """
     #: Id used to identify the task in logger messages.
-    id = Unicode()
+    id = Str()
 
     #: Task to execute.
     task = Value()
@@ -145,10 +145,10 @@ class Engine(Declarative):
 
     """
     #: Unique name used to identify the engine. Should be user understandable.
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: Description of the engine
-    description = d_(Unicode())
+    description = d_(Str())
 
     @d_func
     def new(self, workbench, default=True):
diff --git a/exopy/measurement/engines/process_engine/engine_declaration.enaml b/exopy/measurement/engines/process_engine/engine_declaration.enaml
index 179b200d..48fd3ef1 100644
--- a/exopy/measurement/engines/process_engine/engine_declaration.enaml
+++ b/exopy/measurement/engines/process_engine/engine_declaration.enaml
@@ -9,7 +9,7 @@
 """Declaration of the ProcessEngine and workspace related contribution.
 
 """
-from atom.api import Atom, Bool, Unicode
+from atom.api import Atom, Bool, Str
 from enaml.workbench.api import PluginManifest, Extension
 from enaml.widgets.api import DockItem, Container, Menu, Action
 from enaml.layout.api import InsertItem, RemoveItem
@@ -25,7 +25,7 @@ class ProcFilter(Atom):
 
     """
     #: Name of the process from which to accept records.
-    process_name = Unicode('exopy.MeasureProcess')
+    process_name = Str('exopy.MeasureProcess')
 
     # Bool indicating whether to reject if the process name is wrong (False),
     # or reject if the process name is right (True).
diff --git a/exopy/measurement/measurement.py b/exopy/measurement/measurement.py
index 10d330cb..0d0f3a13 100644
--- a/exopy/measurement/measurement.py
+++ b/exopy/measurement/measurement.py
@@ -15,7 +15,7 @@
 from itertools import chain
 from datetime import date, datetime
 
-from atom.api import (Atom, Dict, Unicode, Typed, ForwardTyped, Bool, Enum,
+from atom.api import (Atom, Dict, Str, Typed, ForwardTyped, Bool, Enum,
                       Value)
 from configobj import ConfigObj
 
@@ -316,12 +316,12 @@ class Measurement(HasPrefAtom):
 
     """
     #: Name of the measurement.
-    name = Unicode().tag(pref=True)
+    name = Str().tag(pref=True)
 
     #: Id of that particular iteration of the measurement. This value is used
     #: when saving the measurement before running it. It is also communicated
     #: to the root task
-    id = Unicode().tag(pref=True)
+    id = Str().tag(pref=True)
 
     #: Current measurement status.
     status = Enum('READY', 'RUNNING', 'PAUSING', 'PAUSED', 'RESUMING',
@@ -329,10 +329,10 @@ class Measurement(HasPrefAtom):
                   'INTERRUPTED')
 
     #: Detailed information about the measurement status.
-    infos = Unicode()
+    infos = Str()
 
     #: Path to the last file in which that measurement was saved.
-    path = Unicode()
+    path = Str()
 
     #: Root task holding the measurement logic.
     root_task = Typed(RootTask)
diff --git a/exopy/measurement/monitors/text_monitor/custom_entry_edition.enaml b/exopy/measurement/monitors/text_monitor/custom_entry_edition.enaml
index 5e6a8b9a..498fd6cf 100644
--- a/exopy/measurement/monitors/text_monitor/custom_entry_edition.enaml
+++ b/exopy/measurement/monitors/text_monitor/custom_entry_edition.enaml
@@ -11,7 +11,7 @@
 """
 from collections import Counter
 
-from atom.api import (Atom, Unicode, List, Dict)
+from atom.api import (Atom, Str, List, Dict)
 from enaml.widgets.api import (ObjectCombo, Dialog, Container, Field, Label,
                                PushButton)
 from enaml.layout.api import hbox, vbox, spacer
@@ -26,7 +26,7 @@ class _Entry(Atom):
 
     """
     #: Selected database entry.
-    entry = Unicode()
+    entry = Str()
 
     #: All database entries that can be used.
     entries = List()
diff --git a/exopy/measurement/monitors/text_monitor/entry.py b/exopy/measurement/monitors/text_monitor/entry.py
index 72c80a1e..417d19e1 100644
--- a/exopy/measurement/monitors/text_monitor/entry.py
+++ b/exopy/measurement/monitors/text_monitor/entry.py
@@ -9,7 +9,7 @@
 """Entries that can be displayed by the text monitor.
 
 """
-from atom.api import (Unicode, List)
+from atom.api import (Str, List)
 from enaml.application import deferred_call
 
 from exopy.utils.atom_util import HasPrefAtom
@@ -20,16 +20,16 @@ class MonitoredEntry(HasPrefAtom):
 
     """
     #: User understandable name of the monitored entry.
-    name = Unicode().tag(pref=True)
+    name = Str().tag(pref=True)
 
     #: Full name of the entry as found or built from the database.
-    path = Unicode().tag(pref=True)
+    path = Str().tag(pref=True)
 
     #: Formatting of the entry.
-    formatting = Unicode().tag(pref=True)
+    formatting = Str().tag(pref=True)
 
     #: Current value that the monitor should display.
-    value = Unicode()
+    value = Str()
 
     #: List of database entries the entry depend_on.
     depend_on = List().tag(pref=True)
diff --git a/exopy/measurement/monitors/text_monitor/rules/base.py b/exopy/measurement/monitors/text_monitor/rules/base.py
index 06d64b8a..cba231ed 100644
--- a/exopy/measurement/monitors/text_monitor/rules/base.py
+++ b/exopy/measurement/monitors/text_monitor/rules/base.py
@@ -12,7 +12,7 @@
 """
 from inspect import cleandoc
 
-from atom.api import Unicode, List, Dict
+from atom.api import Str, List, Dict
 from enaml.core.api import Declarative, d_
 
 from .....utils.traceback import format_exc
@@ -26,17 +26,17 @@ class BaseRule(HasPrefAtom):
 
     """
     #: Name of the rule.
-    id = Unicode().tag(pref=True)
+    id = Str().tag(pref=True)
 
     #: Quick description of what this rule is intended for.
-    description = d_(Unicode()).tag(pref=True)
+    description = d_(Str()).tag(pref=True)
 
     #: List of database entries suffixes used to identify the entries which
     #: contributes to the rule.
     suffixes = List(default=['']).tag(pref=True)
 
     #: Id of the class used for persistence.
-    class_id = Unicode().tag(pref=True)
+    class_id = Str().tag(pref=True)
 
     def try_apply(self, new_entry, monitor):
         """ Attempt to apply the rule.
@@ -75,11 +75,11 @@ class RuleType(Declarator):
     #: name preceded by ':'.
     #: ex: exopy.measurement.monitors.text_monitor.std_rules:RejectRule
     #: The path of any parent GroupDeclarator object will be prepended to it.
-    rule = d_(Unicode())
+    rule = d_(Str())
 
     #: Path to the view object associated with the task.
     #: The path of any parent GroupDeclarator object will be prepended to it.
-    view = d_(Unicode())
+    view = d_(Str())
 
     def register(self, collector, traceback):
         """Collect rule and view and store them into the DeclaratorCollector
@@ -189,14 +189,14 @@ class RuleConfig(Declarative):
 
     """
     #: Id of this rule configuration this should be unique.
-    id = d_(Unicode())
+    id = d_(Str())
 
     #: Quick description of what this rule is intended for.
-    description = d_(Unicode())
+    description = d_(Str())
 
     #: Id of the rule to use. This is dot separated string containing the
     #: name of the package defining the rule type and the rule type name.
-    rule_type = d_(Unicode())
+    rule_type = d_(Str())
 
     #: Configuration dictionary to use to instantiate the rule
     config = d_(Dict())
diff --git a/exopy/measurement/monitors/text_monitor/rules/std_rules.py b/exopy/measurement/monitors/text_monitor/rules/std_rules.py
index 78432756..08aa3956 100644
--- a/exopy/measurement/monitors/text_monitor/rules/std_rules.py
+++ b/exopy/measurement/monitors/text_monitor/rules/std_rules.py
@@ -10,7 +10,7 @@
 TextMonitor.
 
 """
-from atom.api import (Unicode, Bool)
+from atom.api import (Str, Bool)
 
 from ..entry import MonitoredEntry
 from .base import BaseRule
@@ -42,10 +42,10 @@ class FormatRule(BaseRule):
     """
     #: The format in which the new entry created by the rule should be
     #: displayed
-    new_entry_formatting = Unicode().tag(pref=True)
+    new_entry_formatting = Str().tag(pref=True)
 
     #: The suffix of the new entry created by the rule.
-    new_entry_suffix = Unicode().tag(pref=True)
+    new_entry_suffix = Str().tag(pref=True)
 
     #: Whether or not to hide the entries used by the rules.
     hide_entries = Bool(True).tag(pref=True)
diff --git a/exopy/measurement/plugin.py b/exopy/measurement/plugin.py
index 76a89390..d4a2758b 100644
--- a/exopy/measurement/plugin.py
+++ b/exopy/measurement/plugin.py
@@ -13,7 +13,7 @@
 import os
 from functools import partial
 
-from atom.api import Typed, Unicode, List, ForwardTyped, Enum, Bool, Dict
+from atom.api import Typed, Str, List, ForwardTyped, Enum, Bool, Dict
 
 from ..utils.plugin_tools import (HasPreferencesPlugin, ExtensionsCollector,
                                   make_extension_validator)
@@ -76,7 +76,7 @@ class MeasurementPlugin(HasPreferencesPlugin):
 
     #: Reference to the last directory from/in which a measurement was
     #: loaded/saved
-    path = Unicode().tag(pref=True)
+    path = Str().tag(pref=True)
 
     #: Currently edited measurements.
     edited_measurements = Typed(MeasurementContainer, ())
@@ -91,7 +91,7 @@ class MeasurementPlugin(HasPreferencesPlugin):
     engines = List()
 
     #: Currently selected engine represented by its id.
-    selected_engine = Unicode().tag(pref=True)
+    selected_engine = Str().tag(pref=True)
 
     #: What to do of the engine when there is no more measurement to perform.
     engine_policy = Enum('stop', 'sleep').tag(pref=True)
diff --git a/exopy/tasks/configs/base_configs.py b/exopy/tasks/configs/base_configs.py
index 31874c8f..41754010 100644
--- a/exopy/tasks/configs/base_configs.py
+++ b/exopy/tasks/configs/base_configs.py
@@ -11,7 +11,7 @@
 """
 import random
 
-from atom.api import (Atom, Bool, Unicode, Subclass, ForwardTyped, Typed)
+from atom.api import (Atom, Bool, Str, Subclass, ForwardTyped, Typed)
 
 from inspect import getdoc
 
@@ -40,7 +40,7 @@ class BaseTaskConfig(Atom):
     manager = ForwardTyped(task_manager)
 
     #: Name of the task to create.
-    task_name = Unicode()
+    task_name = Str()
 
     #: Class of the task to create.
     task_class = Subclass(BaseTask)
@@ -113,7 +113,7 @@ class PyTaskConfig(BaseTaskConfig):
 
     """
     # Docstring of the class to help pepole know what they are going to create.
-    task_doc = Unicode()
+    task_doc = Str()
 
     def __init__(self, **kwargs):
         super(PyTaskConfig, self).__init__(**kwargs)
@@ -131,10 +131,10 @@ class TemplateTaskConfig(BaseTaskConfig):
 
     """
     #: Path to the file storing the hierarchy.
-    template_path = Unicode()
+    template_path = Str()
 
     #: Description of the template.
-    template_doc = Unicode()
+    template_doc = Str()
 
     def __init__(self, **kwargs):
         super(TemplateTaskConfig, self).__init__(**kwargs)
diff --git a/exopy/tasks/configs/loop_config.py b/exopy/tasks/configs/loop_config.py
index 440be2e5..8e6151ae 100644
--- a/exopy/tasks/configs/loop_config.py
+++ b/exopy/tasks/configs/loop_config.py
@@ -9,7 +9,7 @@
 """Configurer dedicated to the LoopTask allowing to specify a task to embed.
 
 """
-from atom.api import (Typed, Unicode, Bool)
+from atom.api import (Typed, Str, Bool)
 
 from .base_configs import PyTaskConfig, BaseTaskConfig
 from .base_config_views import BaseConfigView
@@ -23,7 +23,7 @@ class LoopTaskConfig(PyTaskConfig):
     use_subtask = Bool()
 
     #: Embedded task id.
-    subtask = Unicode()
+    subtask = Str()
 
     #: Configurer for the subtask.
     subconfig = Typed(BaseTaskConfig)
diff --git a/exopy/tasks/declarations.py b/exopy/tasks/declarations.py
index 94a3a726..1643b243 100644
--- a/exopy/tasks/declarations.py
+++ b/exopy/tasks/declarations.py
@@ -11,7 +11,7 @@
 """
 from inspect import cleandoc
 
-from atom.api import Unicode, List, Value, Dict, Property
+from atom.api import Str, List, Value, Dict, Property
 from enaml.core.api import d_, d_func
 
 from .infos import TaskInfos, InterfaceInfos, ConfigInfos
@@ -59,11 +59,11 @@ class Task(Declarator):
     #: updated that way), one can specify the name of the top level package
     #: in which the task is defined followed by its name.
     #: ex: exopy.LoopTask
-    task = d_(Unicode())
+    task = d_(Str())
 
     #: Path to the view object associated with the task.
     #: The path of any parent GroupDeclarator object will be prepended to it.
-    view = d_(Unicode())
+    view = d_(Str())
 
     #: Metadata associated to the task. ex : loopable = True
     metadata = d_(Dict())
@@ -265,7 +265,7 @@ class Interface(Declarator):
     #: Example :
     #: exopy.tasks.tasks.logic.loop_linspace_interface:LinspaceLoopInterface
     #: The path of any parent GroupDeclarator object will be prepended to it.
-    interface = d_(Unicode())
+    interface = d_(Str())
 
     #: Path or tuple of paths to the view objects associated with the interface
     #: The path of any parent GroupDeclarator object will be prepended to it.
@@ -513,11 +513,11 @@ class TaskConfig(Declarator):
     #: name preceded by ':'.
     #: ex: exopy.tasks.config.base_config:PyConfigTask
     #: The path of any parent GroupDeclarator object will be prepended to it.
-    config = d_(Unicode())
+    config = d_(Str())
 
     #: Path to the view object associated with the task.
     #: The path of any parent GroupDeclarator object will be prepended to it.
-    view = d_(Unicode())
+    view = d_(Str())
 
     #: Id of the config computed from the top-level package and the config name
     id = Property(cached=True)
diff --git a/exopy/tasks/filters.py b/exopy/tasks/filters.py
index f5dab8ca..81fd6d01 100644
--- a/exopy/tasks/filters.py
+++ b/exopy/tasks/filters.py
@@ -11,7 +11,7 @@
 The filter available by default are declared in the manager manifest.
 
 """
-from atom.api import Value, Subclass, Unicode, Property, set_default
+from atom.api import Value, Subclass, Str, Property, set_default
 from enaml.core.api import d_func, d_
 
 from .tasks.base_tasks import BaseTask
@@ -23,7 +23,7 @@ class TaskFilter(Declarator):
 
     """
     #: Unique id of this filter (also used as a name).
-    id = d_(Unicode())
+    id = d_(Str())
 
     @d_func
     def filter_tasks(self, tasks, templates):
@@ -69,7 +69,7 @@ class MetadataTaskFilter(TaskFilter):
 
     """
     #: Metadata key to match.
-    meta_key = d_(Unicode())
+    meta_key = d_(Str())
 
     #: Metadata value to match.
     meta_value = d_(Value())
@@ -90,7 +90,7 @@ class GroupTaskFilter(MetadataTaskFilter):
 
     """
     #: Group to which the tasks must belong.
-    group = d_(Unicode())
+    group = d_(Str())
 
     meta_key = set_default('group')
 
diff --git a/exopy/tasks/infos.py b/exopy/tasks/infos.py
index dcb00e02..8e39794d 100644
--- a/exopy/tasks/infos.py
+++ b/exopy/tasks/infos.py
@@ -9,7 +9,7 @@
 """Objects used to store tasks, interfaces and configs in the manager.
 
 """
-from atom.api import (Atom, List, Subclass, Dict, Coerced, Typed, Unicode,
+from atom.api import (Atom, List, Subclass, Dict, Coerced, Typed, Str,
                       set_default)
 import enaml
 
@@ -39,11 +39,11 @@ class ObjectDependentInfos(Atom):
     """
     #: Id of the runtime dependency analyser to use for driver detection to add
     #: to the dependencies if instruments is set.
-    DRIVER_ANALYSER = Unicode()
+    DRIVER_ANALYSER = Str()
 
     #: Id of the runtime dependency analyser to use for profile detection to
     #: add to the dependencies if instruments is set.
-    PROFILE_ANALYSER = Unicode()
+    PROFILE_ANALYSER = Str()
 
     #: Set of instrument supported by this task. This should never be updated
     #: in place, it should always be copied and replaced by the new value.
diff --git a/exopy/tasks/plugin.py b/exopy/tasks/plugin.py
index 6f854615..b74a8b02 100644
--- a/exopy/tasks/plugin.py
+++ b/exopy/tasks/plugin.py
@@ -13,7 +13,7 @@
 import logging
 from collections import defaultdict
 
-from atom.api import List, Dict, Typed, Unicode
+from atom.api import List, Dict, Typed, Str
 from watchdog.observers import Observer
 
 from .declarations import (Task, Interface, Tasks, Interfaces, TaskConfig,
@@ -45,7 +45,7 @@ class TaskManagerPlugin(HasPreferencesPlugin):
     filters = List()
 
     #: Path to the file in which the names for the tasks are located.
-    auto_task_path = Unicode(os.path.join(FOLDER_PATH,
+    auto_task_path = Str(os.path.join(FOLDER_PATH,
                                           'tasknames.txt')).tag(pref=True)
 
     #: List of names to use when creating a new task.
diff --git a/exopy/tasks/tasks/base_tasks.py b/exopy/tasks/tasks/base_tasks.py
index e924ca0d..8a564a35 100644
--- a/exopy/tasks/tasks/base_tasks.py
+++ b/exopy/tasks/tasks/base_tasks.py
@@ -24,7 +24,7 @@
 from cProfile import Profile
 from operator import attrgetter
 
-from atom.api import (Atom, Int, Bool, Value, Unicode, List,
+from atom.api import (Atom, Int, Bool, Value, Str, List,
                       ForwardTyped, Typed, Callable, Dict, Signal,
                       Tuple, Coerced, Constant, set_default)
 from configobj import Section, ConfigObj
@@ -70,10 +70,10 @@ class BaseTask(Atom):
     dep_type = Constant(DEP_TYPE).tag(pref=True)
 
     #: Name of the class, used for persistence.
-    task_id = Unicode().tag(pref=True)
+    task_id = Str().tag(pref=True)
 
     #: Name of the task this should be unique in hierarchy.
-    name = Unicode().tag(pref=True)
+    name = Str().tag(pref=True)
 
     #: Depth of the task in the hierarchy. this should not be manipulated
     #: directly by user code.
@@ -88,11 +88,11 @@ class BaseTask(Atom):
     #: Entries the task declares in the database and the associated default
     #: values. This should be copied and re-assign when modified not modfied
     #: in place.
-    database_entries = Dict(Unicode(), Value())
+    database_entries = Dict(Str(), Value())
 
     #: Path of the task in the hierarchy. This refers to the parent task and
     #: is used when writing in the database.
-    path = Unicode()
+    path = Str()
 
     #: Reference to the root task in the hierarchy.
     root = ForwardTyped(lambda: RootTask)
@@ -110,14 +110,14 @@ class BaseTask(Atom):
 
     #: Dictionary indicating whether the task is executed in parallel
     #: ('activated' key) and which is pool it belongs to ('pool' key).
-    parallel = Dict(Unicode()).tag(pref=True)
+    parallel = Dict(Str()).tag(pref=True)
 
     #: Dictionary indicating whether the task should wait on any pool before
     #: performing its job. Three valid keys can be used :
     #: - 'activated' : a bool indicating whether or not to wait.
     #: - 'wait' : the list should then specify which pool should be waited.
     #: - 'no_wait' : the list should specify which pool not to wait on.
-    wait = Dict(Unicode()).tag(pref=True)
+    wait = Dict(Str()).tag(pref=True)
 
     #: Dict of access exception in the database. This should not be manipulated
     #: by user code.
@@ -1042,7 +1042,7 @@ class RootTask(ComplexTask):
 
     """
     #: Path to which log infos, preferences, etc should be written by default.
-    default_path = Unicode('').tag(pref=True)
+    default_path = Str('').tag(pref=True)
 
     #: Should the execution be profiled.
     should_profile = Bool().tag(pref=True)
diff --git a/exopy/tasks/tasks/decorators.py b/exopy/tasks/tasks/decorators.py
index 6e10ef4b..025a070b 100644
--- a/exopy/tasks/tasks/decorators.py
+++ b/exopy/tasks/tasks/decorators.py
@@ -17,7 +17,7 @@
 from time import sleep
 from threading import Thread, Event, current_thread
 
-from atom.api import Atom, Value, Callable, Unicode
+from atom.api import Atom, Value, Callable, Str
 
 from ...utils.traceback import format_exc
 
@@ -185,7 +185,7 @@ def stop(self):
     _func = Callable()
 
     #: Pool id to which this dispatcher belongs.
-    _pool = Unicode()
+    _pool = Str()
 
     def _background_loop(self):
         """Background function executed by the thread.
diff --git a/exopy/tasks/tasks/logic/conditional_task.py b/exopy/tasks/tasks/logic/conditional_task.py
index 890b19ab..50ae42db 100644
--- a/exopy/tasks/tasks/logic/conditional_task.py
+++ b/exopy/tasks/tasks/logic/conditional_task.py
@@ -9,7 +9,7 @@
 """Task equivalent to an if statement.
 
 """
-from atom.api import (Unicode)
+from atom.api import (Str)
 
 from ..validators import Feval
 from ..base_tasks import ComplexTask
@@ -20,7 +20,7 @@ class ConditionalTask(ComplexTask):
 
     """
     #: Condition to meet in order to perform the children tasks.
-    condition = Unicode().tag(pref=True, feval=Feval())
+    condition = Str().tag(pref=True, feval=Feval())
 
     def perform(self):
         """Call the children task if the condition evaluate to True.
diff --git a/exopy/tasks/tasks/logic/loop_exceptions_tasks.py b/exopy/tasks/tasks/logic/loop_exceptions_tasks.py
index b171a6f0..c5b4dc15 100644
--- a/exopy/tasks/tasks/logic/loop_exceptions_tasks.py
+++ b/exopy/tasks/tasks/logic/loop_exceptions_tasks.py
@@ -9,7 +9,7 @@
 """Tasks used to modify the execution of a loop.
 
 """
-from atom.api import (Unicode, set_default)
+from atom.api import (Str, set_default)
 
 from ..validators import Feval
 from ..base_tasks import SimpleTask
@@ -25,7 +25,7 @@ class BreakTask(SimpleTask):
 
     """
     #: Condition under which to perform the break.
-    condition = Unicode().tag(pref=True, feval=Feval())
+    condition = Str().tag(pref=True, feval=Feval())
 
     #: Never run this task in parallel.
     parallel = set_default({'forbidden': True})
@@ -59,7 +59,7 @@ class ContinueTask(SimpleTask):
 
     """
     #: Condition under which to continue.
-    condition = Unicode().tag(pref=True, feval=Feval())
+    condition = Str().tag(pref=True, feval=Feval())
 
     #: Never run this task in parallel.
     parallel = set_default({'forbidden': True})
diff --git a/exopy/tasks/tasks/logic/loop_iterable_interface.py b/exopy/tasks/tasks/logic/loop_iterable_interface.py
index 9e595cd3..4a982bc2 100644
--- a/exopy/tasks/tasks/logic/loop_iterable_interface.py
+++ b/exopy/tasks/tasks/logic/loop_iterable_interface.py
@@ -11,7 +11,7 @@
 """
 import numpy as np
 
-from atom.api import Unicode
+from atom.api import Str
 from collections import Iterable
 
 from ..task_interface import TaskInterface
@@ -23,7 +23,7 @@ class IterableLoopInterface(TaskInterface):
 
     """
     #: Iterable on which to iterate.
-    iterable = Unicode('range(10)').tag(pref=True, feval=Feval(types=Iterable))
+    iterable = Str('range(10)').tag(pref=True, feval=Feval(types=Iterable))
 
     def check(self, *args, **kwargs):
         """Check that the iterable member evaluation does yield an iterable.
diff --git a/exopy/tasks/tasks/logic/loop_linspace_interface.py b/exopy/tasks/tasks/logic/loop_linspace_interface.py
index c2837da5..2aa3be2b 100644
--- a/exopy/tasks/tasks/logic/loop_linspace_interface.py
+++ b/exopy/tasks/tasks/logic/loop_linspace_interface.py
@@ -13,7 +13,7 @@
 from decimal import Decimal
 
 import numpy as np
-from atom.api import Unicode
+from atom.api import Str
 
 from ..task_interface import TaskInterface
 from ..validators import Feval
@@ -24,13 +24,13 @@ class LinspaceLoopInterface(TaskInterface):
 
     """
     #: Value at which to start the loop.
-    start = Unicode('0.0').tag(pref=True, feval=Feval(types=numbers.Real))
+    start = Str('0.0').tag(pref=True, feval=Feval(types=numbers.Real))
 
     #: Value at which to stop the loop (included)
-    stop = Unicode('1.0').tag(pref=True, feval=Feval(types=numbers.Real))
+    stop = Str('1.0').tag(pref=True, feval=Feval(types=numbers.Real))
 
     #: Step between loop values.
-    step = Unicode('0.1').tag(pref=True, feval=Feval(types=numbers.Real))
+    step = Str('0.1').tag(pref=True, feval=Feval(types=numbers.Real))
 
     def check(self, *args, **kwargs):
         """Check evaluation of all loop parameters.
diff --git a/exopy/tasks/tasks/logic/while_task.py b/exopy/tasks/tasks/logic/while_task.py
index 14c8d4fb..d713a81a 100644
--- a/exopy/tasks/tasks/logic/while_task.py
+++ b/exopy/tasks/tasks/logic/while_task.py
@@ -9,7 +9,7 @@
 """Task allowing to use a while statement.
 
 """
-from atom.api import (Unicode, set_default)
+from atom.api import (Str, set_default)
 
 from ..validators import Feval
 from ..base_tasks import ComplexTask
@@ -24,7 +24,7 @@ class WhileTask(ComplexTask):
 
     """
     #: Condition under which to continue looping.
-    condition = Unicode().tag(pref=True, feval=Feval())
+    condition = Str().tag(pref=True, feval=Feval())
 
     database_entries = set_default({'index': 1})
 
diff --git a/exopy/tasks/tasks/task_editor.enaml b/exopy/tasks/tasks/task_editor.enaml
index f84746e5..938b147b 100644
--- a/exopy/tasks/tasks/task_editor.enaml
+++ b/exopy/tasks/tasks/task_editor.enaml
@@ -12,7 +12,7 @@
 from itertools import chain
 from functools import partial
 
-from atom.api import (Typed, Unicode, Constant, Bool, Value, Dict,
+from atom.api import (Typed, Str, Constant, Bool, Value, Dict,
                       set_default)
 from enaml.core.declarative import d_, d_func
 from enaml.widgets.api import Container, Stack, StackItem, PushButton, Label
diff --git a/exopy/tasks/tasks/task_interface.py b/exopy/tasks/tasks/task_interface.py
index cfb03a66..5be666e4 100644
--- a/exopy/tasks/tasks/task_interface.py
+++ b/exopy/tasks/tasks/task_interface.py
@@ -9,7 +9,7 @@
 """Definition of the base classes for interfaces in tasks.
 
 """
-from atom.api import (Atom, ForwardTyped, Typed, Unicode, Dict, Property,
+from atom.api import (Atom, ForwardTyped, Typed, Str, Dict, Property,
                       Constant)
 
 from ...utils.traceback import format_exc
@@ -283,7 +283,7 @@ class BaseInterface(HasPrefAtom):
 
     #: Id of the interface preceded by the ids of all its anchors separated by
     # ':'. Used for persistence purposes.
-    interface_id = Unicode().tag(pref=True)
+    interface_id = Str().tag(pref=True)
 
     #: Dict of database entries added by the interface.
     database_entries = Dict()
diff --git a/exopy/tasks/tasks/util/log_task.py b/exopy/tasks/tasks/util/log_task.py
index 95e8a14c..d2670025 100644
--- a/exopy/tasks/tasks/util/log_task.py
+++ b/exopy/tasks/tasks/util/log_task.py
@@ -9,7 +9,7 @@
 """Logging Task.
 
 """
-from atom.api import (Unicode, set_default)
+from atom.api import (Str, set_default)
 import logging
 
 from ..base_tasks import SimpleTask
@@ -20,7 +20,7 @@ class LogTask(SimpleTask):
 
     """
     #: Message to log when the task is executed.
-    message = Unicode().tag(pref=True, fmt=True)
+    message = Str().tag(pref=True, fmt=True)
 
     database_entries = set_default({'message': ''})
 
diff --git a/exopy/tasks/tasks/util/sleep_task.py b/exopy/tasks/tasks/util/sleep_task.py
index e94d1d3d..d1ebb721 100644
--- a/exopy/tasks/tasks/util/sleep_task.py
+++ b/exopy/tasks/tasks/util/sleep_task.py
@@ -11,7 +11,7 @@
 
 """
 import numbers
-from atom.api import (Unicode, set_default)
+from atom.api import (Str, set_default)
 from time import sleep
 
 from ..base_tasks import SimpleTask
@@ -23,7 +23,7 @@ class SleepTask(SimpleTask):
     Wait for any parallel operation before execution by default.
     """
     # Time to wait
-    time = Unicode().tag(pref=True, feval=Feval(types=numbers.Real))
+    time = Str().tag(pref=True, feval=Feval(types=numbers.Real))
 
     wait = set_default({'': True})
 
diff --git a/exopy/tasks/widgets/building.enaml b/exopy/tasks/widgets/building.enaml
index fa39d576..64cc0eb8 100644
--- a/exopy/tasks/widgets/building.enaml
+++ b/exopy/tasks/widgets/building.enaml
@@ -9,7 +9,7 @@
 """Widgets dedicated to the construction of new tasks.
 
 """
-from atom.api import (Atom, Typed, Unicode, ForwardTyped, Bool, observe)
+from atom.api import (Atom, Typed, Str, ForwardTyped, Bool, observe)
 from enaml.core.api import Include
 from enaml.widgets.widget import Widget
 from enaml.layout.api import hbox, spacer, vbox
diff --git a/exopy/tasks/widgets/saving.enaml b/exopy/tasks/widgets/saving.enaml
index 23105cee..bdad04fc 100644
--- a/exopy/tasks/widgets/saving.enaml
+++ b/exopy/tasks/widgets/saving.enaml
@@ -12,7 +12,7 @@
 import os
 from textwrap import fill
 
-from atom.api import (Atom, Unicode, Bool, ForwardTyped, observe)
+from atom.api import (Atom, Str, Bool, ForwardTyped, observe)
 from enaml.widgets.api import (Container, Field, MultilineField, CheckBox,
                                PushButton, Dialog)
 from enaml.layout.api import align, hbox, vbox, spacer
@@ -36,13 +36,13 @@ class TemplateSaverModel(Atom):
     manager = ForwardTyped(task_manager)
 
     #: Currently selected folder in which to save the template.
-    folder = Unicode()
+    folder = Str()
 
     #: File in which to save the template.
-    filename = Unicode()
+    filename = Str()
 
     #: Documentation for the template.
-    doc = Unicode()
+    doc = Str()
 
     #: Flag indicating whether or not enough informations have been provided
     #: to porceed with saving.
diff --git a/exopy/utils/atom_util.py b/exopy/utils/atom_util.py
index 82066cf4..dd97e7b6 100644
--- a/exopy/utils/atom_util.py
+++ b/exopy/utils/atom_util.py
@@ -14,7 +14,7 @@
 from ast import literal_eval
 
 from textwrap import fill
-from atom.api import Str, Unicode, Enum, Atom, Constant
+from atom.api import Str, Str, Enum, Atom, Constant
 
 from inspect import getfullargspec
 from inspect import cleandoc
@@ -84,10 +84,10 @@ def member_from_pref(obj, member, val):
 
     # If 'pref=True' then we rely on the standard save mechanism
     if meta_value is True:
-        # If the member is a subclass of Str, Unicode then we just take the
+        # If the member is a subclass of Str, Str then we just take the
         # raw value and Atom will handle the casting if any for us.
         # If it is a subclass of basestring then we save it as-is
-        if isinstance(member, (Str, Unicode)):
+        if isinstance(member, (Str, Str)):
             value = val
 
         # If it is an Enum where the first item is a (subclass of) string, then
diff --git a/exopy/utils/container_change.py b/exopy/utils/container_change.py
index c6fa087a..b7a473cc 100644
--- a/exopy/utils/container_change.py
+++ b/exopy/utils/container_change.py
@@ -9,7 +9,7 @@
 """Payload to use when notifying the system about a container change.
 
 """
-from atom.api import (Atom, Value, Unicode, List)
+from atom.api import (Atom, Value, Str, List)
 
 
 class ContainerChange(Atom):
@@ -20,7 +20,7 @@ class ContainerChange(Atom):
     obj = Value()
 
     #: Name of the modified container.
-    name = Unicode()
+    name = Str()
 
     #: List of added entries. Should not be manipulated directly by user code.
     #: Use the add_operation method to add operations.
diff --git a/exopy/utils/declarator.py b/exopy/utils/declarator.py
index 58661bab..a49890a2 100644
--- a/exopy/utils/declarator.py
+++ b/exopy/utils/declarator.py
@@ -12,7 +12,7 @@
 import re
 from importlib import import_module
 
-from atom.api import Unicode, Bool
+from atom.api import Str, Bool
 from enaml.core.api import Declarative, d_
 
 from .traceback import format_exc
@@ -96,11 +96,11 @@ class GroupDeclarator(Declarator):
     """
     #: Prefix path to use for all children Declarator. Path should be dot
     #: separated.
-    path = d_(Unicode())
+    path = d_(Str())
 
     #: Id of the group common to all children Declarator. It is the
     #: responsability of the children to mention they are part of a group.
-    group = d_(Unicode())
+    group = d_(Str())
 
     def get_path(self):
         """Overriden method to walk all parents.
diff --git a/exopy/utils/plugin_tools.py b/exopy/utils/plugin_tools.py
index b51755af..b89535e5 100644
--- a/exopy/utils/plugin_tools.py
+++ b/exopy/utils/plugin_tools.py
@@ -12,7 +12,7 @@
 import sys
 from collections import defaultdict
 
-from atom.api import Atom, Dict, Unicode, Coerced, Typed, Callable, List
+from atom.api import Atom, Dict, Str, Coerced, Typed, Callable, List
 from enaml.workbench.api import Workbench, Plugin
 
 from .atom_util import (update_members_from_preferences,
@@ -137,7 +137,7 @@ class BaseCollector(Atom):
     workbench = Typed(Workbench)
 
     #: Id of the extension point to observe.
-    point = Unicode()
+    point = Str()
 
     #: Expected class(es) of the object generated by the extension.
     ext_class = Coerced(ClassTuple)
diff --git a/exopy/utils/widgets/dict_tree_view.enaml b/exopy/utils/widgets/dict_tree_view.enaml
index d464aeb1..7e4e2b9b 100644
--- a/exopy/utils/widgets/dict_tree_view.enaml
+++ b/exopy/utils/widgets/dict_tree_view.enaml
@@ -11,7 +11,7 @@
 """
 from collections import Mapping
 
-from atom.api import Atom, Typed, Value, Unicode, ForwardTyped, List
+from atom.api import Atom, Typed, Value, Str, ForwardTyped, List
 
 from .qt_tree_widget import QtTreeWidget
 from .tree_nodes import TreeNode
@@ -22,7 +22,7 @@ class Leaf(Atom):
 
     """
     #: Key under which the value is stored.
-    name = Unicode()
+    name = Str()
 
     #: Value associated with the name.
     value = Value()
@@ -33,7 +33,7 @@ class Node(Atom):
 
     """
     #: Key under which the mapping is stored or blank if this is the root node.
-    name = Unicode()
+    name = Str()
 
     #: Nodes generated from the key/value pairs of the mapping.
     nodes = List()
diff --git a/exopy/utils/widgets/list_editor.enaml b/exopy/utils/widgets/list_editor.enaml
index 03cd11b4..291f5fd1 100644
--- a/exopy/utils/widgets/list_editor.enaml
+++ b/exopy/utils/widgets/list_editor.enaml
@@ -14,7 +14,7 @@ responsability of the model to signal internal changes to the list.
 
 """
 from functools import partial
-from atom.api import Unicode, List
+from atom.api import Str, List
 from enaml.core.api import Looper, Conditional
 from enaml.core.declarative import d_
 from enaml.layout.api import hbox, align, spacer, grid, vbox
@@ -90,7 +90,7 @@ class ListContainer(Container):
 
     """
     #: Aligmenent of the PushButton used to edit the list content.
-    alignment = d_(Unicode('top'))
+    alignment = d_(Str('top'))
 
     def layout_constraints(self):
         """Layout the push buttons used to edit the list content.
diff --git a/exopy/utils/widgets/qt_autoscroll_html.py b/exopy/utils/widgets/qt_autoscroll_html.py
index 452f52a6..d06aeb93 100644
--- a/exopy/utils/widgets/qt_autoscroll_html.py
+++ b/exopy/utils/widgets/qt_autoscroll_html.py
@@ -9,7 +9,7 @@
 """Html widget automatically scrolling ot show latest added text.
 
 """
-from atom.api import Unicode
+from atom.api import Str
 from enaml.core.declarative import d_
 from enaml.qt import QtGui, QtWidgets
 from enaml.widgets.api import RawWidget
@@ -23,7 +23,7 @@ class QtAutoscrollHtml(RawWidget):
 
     """
     #: Text displayed by the widget. Any Html mark up will be rendered.
-    text = d_(Unicode())
+    text = d_(Str())
 
     hug_width = 'ignore'
     hug_height = 'ignore'
diff --git a/exopy/utils/widgets/qt_completers.py b/exopy/utils/widgets/qt_completers.py
index 6b3d26a6..304880e5 100644
--- a/exopy/utils/widgets/qt_completers.py
+++ b/exopy/utils/widgets/qt_completers.py
@@ -9,7 +9,7 @@
 """Widgets with support for text completion.
 
 """
-from atom.api import List, Tuple, Unicode, Bool, Callable, Value
+from atom.api import List, Tuple, Str, Bool, Callable, Value
 from enaml.core.declarative import d_
 from enaml.qt import QtCore, QtWidgets
 from enaml.widgets.api import RawWidget, Feature
@@ -139,7 +139,7 @@ class QtLineCompleter(RawWidget):
 
     """
     #: Text being edited by this widget.
-    text = d_(Unicode())
+    text = d_(Str())
 
     #: Static list of entries used to propose completion. This member value is
     #: not updated by the entries_updater.
@@ -149,7 +149,7 @@ class QtLineCompleter(RawWidget):
     entries_updater = d_(Callable())
 
     #: Delimiters marking the begining and end of completed section.
-    delimiters = d_(Tuple(Unicode(), ('{', '}')))
+    delimiters = d_(Tuple(Str(), ('{', '}')))
 
     hug_width = 'ignore'
     features = Feature.FocusEvents
@@ -237,7 +237,7 @@ class QtTextCompleter(RawWidget):
 
     """
     #: Text being edited by this widget.
-    text = d_(Unicode())
+    text = d_(Str())
 
     #: Static list of entries used to propose completion. This member value is
     #: not updated by the entries_updater.
@@ -247,7 +247,7 @@ class QtTextCompleter(RawWidget):
     entries_updater = d_(Callable())
 
     #: Delimiters marking the begining and end of completed section.
-    delimiters = d_(Tuple(Unicode(), ('{', '}')))
+    delimiters = d_(Tuple(Str(), ('{', '}')))
 
     hug_width = 'ignore'
     features = Feature.FocusEvents
diff --git a/exopy/utils/widgets/tree_nodes.py b/exopy/utils/widgets/tree_nodes.py
index ecf938b4..0ca6bdf7 100644
--- a/exopy/utils/widgets/tree_nodes.py
+++ b/exopy/utils/widgets/tree_nodes.py
@@ -9,7 +9,7 @@
 """Declarative node for tree node generation.
 
 """
-from atom.api import (Unicode, Bool, List, Value, Property, Dict)
+from atom.api import (Str, Bool, List, Value, Property, Dict)
 from enaml.core.declarative import Declarative, d_, d_func
 from enaml.widgets.api import Menu
 
@@ -40,18 +40,18 @@ class TreeNode(Declarative):
 
     #: Either the name of a member containing a label, or a constant label, if
     #: the string starts with '='.
-    label = d_(Unicode())
+    label = d_(Str())
 
     #: Either the name of a member containing a tooltip, or constant tooltip,
     #: if the string starts with '='.
-    tooltip = d_(Unicode())
+    tooltip = d_(Str())
 
     #: Name of the member containing children (if '', the node is a leaf).
-    children_member = d_(Unicode())
+    children_member = d_(Str())
 
     #: Name of the signal use to notify changes to the children. The payload of
     #: the signal should be a ContainerChange instance.
-    children_changed = d_(Unicode())
+    children_changed = d_(Str())
 
     #: List of object classes than can be added or copied
     add = d_(List())
@@ -60,7 +60,7 @@ class TreeNode(Declarative):
     move = d_(List())
 
     #: Name to use for a new instance
-    name = d_(Unicode())
+    name = d_(Str())
 
     #: Can the object's children be renamed?
     rename = d_(Bool(True))
@@ -90,16 +90,16 @@ class TreeNode(Declarative):
     node_for_class = Property()
 
     #: Name of leaf item icon
-    icon_item = d_(Unicode('<item>'))
+    icon_item = d_(Str('<item>'))
 
     #: Name of group item icon
-    icon_group = d_(Unicode('<group>'))
+    icon_group = d_(Str('<group>'))
 
     #: Name of opened group item icon
-    icon_open = d_(Unicode('<open>'))
+    icon_open = d_(Str('<open>'))
 
     #: Resource path used to locate the node icon
-    icon_path = d_(Unicode('Icon'))
+    icon_path = d_(Str('Icon'))
 
     #: Selector or name for background color
     background = Value('white')
diff --git a/tests/app/icons/contributions.enaml b/tests/app/icons/contributions.enaml
index f4b64866..88fe97e9 100644
--- a/tests/app/icons/contributions.enaml
+++ b/tests/app/icons/contributions.enaml
@@ -11,7 +11,7 @@
 """
 import enaml.icon
 from enaml.widgets.api import Window, Container, PushButton
-from atom.api import Unicode
+from atom.api import Str
 
 from enaml.workbench.api import Extension, PluginManifest
 from exopy.app.icons.icon_theme import IconTheme, IconThemeExtension, Icon
@@ -21,7 +21,7 @@ class DumbIcon(enaml.icon.Icon):
     """Dumb class for testing.
 
     """
-    id = Unicode()
+    id = Str()
 
 
 enamldef DummyTheme(IconTheme):
diff --git a/tests/app/packages/test_plugin.py b/tests/app/packages/test_plugin.py
index 2149a425..ede6ca5b 100644
--- a/tests/app/packages/test_plugin.py
+++ b/tests/app/packages/test_plugin.py
@@ -11,7 +11,7 @@
 """
 import pytest
 import enaml
-from atom.api import Atom, Bool, Value, Unicode
+from atom.api import Atom, Bool, Value, Str
 
 from exopy.testing.util import handle_dialog
 
@@ -52,7 +52,7 @@ class FalseEntryPoint(Atom):
 
     """
     #: Name of this entry point
-    name = Unicode()
+    name = Str()
 
     #: Flag indicating whether the require method should raise an error.
     missing_require = Bool()
diff --git a/tests/app/preferences/pref_utils.enaml b/tests/app/preferences/pref_utils.enaml
index 7cfa654b..196f4625 100644
--- a/tests/app/preferences/pref_utils.enaml
+++ b/tests/app/preferences/pref_utils.enaml
@@ -9,7 +9,7 @@
 """Preferences plugin test helpers.
 
 """
-from atom.api import Atom, Unicode
+from atom.api import Atom, Str
 from enaml.workbench.api import PluginManifest, Extension
 
 from exopy.utils.plugin_tools import HasPreferencesPlugin
@@ -21,10 +21,10 @@ class _Pref(HasPreferencesPlugin):
 
     """
     #: Non auto saving member.
-    string = Unicode().tag(pref=True)
+    string = Str().tag(pref=True)
 
     #: Member needing to be automatically saved.
-    auto = Unicode().tag(pref=True)
+    auto = Str().tag(pref=True)
 
 
 enamldef PrefContributor(PluginManifest):
diff --git a/tests/app/states/states_utils.enaml b/tests/app/states/states_utils.enaml
index 30073bde..6ca3ede9 100644
--- a/tests/app/states/states_utils.enaml
+++ b/tests/app/states/states_utils.enaml
@@ -9,7 +9,7 @@
 """Dummy plugin to test the state plugin.
 
 """
-from atom.api import Atom, Unicode
+from atom.api import Atom, Str
 from enaml.workbench.api import PluginManifest, Plugin, Extension
 
 from exopy.app.states.state import State
@@ -19,7 +19,7 @@ class _State(Plugin):
     """Dummy plugin having a string member.
 
     """
-    string = Unicode('init')
+    string = Str('init')
 
 
 enamldef StateContributor(PluginManifest):
diff --git a/tests/measurement/engines/test_process_engine.py b/tests/measurement/engines/test_process_engine.py
index f7baa06c..68baf38f 100644
--- a/tests/measurement/engines/test_process_engine.py
+++ b/tests/measurement/engines/test_process_engine.py
@@ -16,7 +16,7 @@
 
 import enaml
 import pytest
-from atom.api import Bool, Unicode, Value
+from atom.api import Bool, Str, Value
 
 from exopy.measurement.engines.api import ExecutionInfos
 from exopy.measurement.engines.process_engine.subprocess import TaskProcess
@@ -36,7 +36,7 @@ class WaitingTask(SimpleTask):
     """
     check_flag = Bool(True).tag(pref=True)
     sync_port = Value(()).tag(pref=True)
-    sock_id = Unicode().tag(pref=True)
+    sock_id = Str().tag(pref=True)
 
     def check(self, *args, **kwargs):
         super(WaitingTask, self).check(*args, **kwargs)
diff --git a/tests/measurement/workspace/test_workspace.py b/tests/measurement/workspace/test_workspace.py
index 73bc5367..2af7e9a1 100644
--- a/tests/measurement/workspace/test_workspace.py
+++ b/tests/measurement/workspace/test_workspace.py
@@ -552,11 +552,11 @@ def test_measurement_execution(workspace, exopy_qtbot):
 
     """
     from exopy.measurement.processor import MeasurementProcessor
-    from atom.api import Unicode, Dict
+    from atom.api import Str, Dict
 
     class P(MeasurementProcessor):
 
-        called = Unicode()
+        called = Str()
 
         args = Dict()
 
diff --git a/tests/tasks/tasks/test_execution.py b/tests/tasks/tasks/test_execution.py
index dc074c04..d0f132f6 100644
--- a/tests/tasks/tasks/test_execution.py
+++ b/tests/tasks/tasks/test_execution.py
@@ -16,7 +16,7 @@
 from time import sleep
 
 import pytest
-from atom.api import Unicode, set_default
+from atom.api import Str, set_default
 from enaml.application import deferred_call
 
 from exopy.tasks.tasks.base_tasks import RootTask, ComplexTask
@@ -58,13 +58,13 @@ class Tester(CheckTask):
             """Class declaring a member to format and one to eval.
 
             """
-            form = Unicode().tag(fmt=True)
+            form = Str().tag(fmt=True)
 
-            feval = Unicode().tag(feval=Feval())
+            feval = Str().tag(feval=Feval())
 
-            feval_warn = Unicode().tag(feval=Feval(warn=True))
+            feval_warn = Str().tag(feval=Feval(warn=True))
 
-            feval_empty = Unicode().tag(feval=SkipEmpty())
+            feval_empty = Str().tag(feval=SkipEmpty())
 
             database_entries = set_default({'form': '', 'feval': 0,
                                             'feval_warn': 0, 'feval_empty': 0})
@@ -111,7 +111,7 @@ class Tester(CheckTask):
             validator.
 
             """
-            feval = Unicode().tag(feval=object())
+            feval = Str().tag(feval=object())
 
         tester = Tester(name='test', feval='2*{test_val}',
                         database_entries={'val': 1, 'feval': 0})
diff --git a/tests/tasks/tasks/test_instr_task.py b/tests/tasks/tasks/test_instr_task.py
index ca6db70a..16610c21 100644
--- a/tests/tasks/tasks/test_instr_task.py
+++ b/tests/tasks/tasks/test_instr_task.py
@@ -9,7 +9,7 @@
 """Test for the instrument task.
 
 """
-from atom.api import Unicode
+from atom.api import Str
 
 from exopy.tasks.tasks.base_tasks import RootTask
 from exopy.tasks.tasks.validators import Feval
@@ -52,7 +52,7 @@ def setup(self):
                                    'settings': {'s': {}}}}}
 
         class InTask(InstrumentTask):
-            feval = Unicode('1').tag(feval=Feval())
+            feval = Str('1').tag(feval=Feval())
 
         self.task = InTask(name='Dummy',
                            selected_instrument=('p', 'd', 'c', 's'))
diff --git a/tests/tasks/tasks/test_task_interfaces.py b/tests/tasks/tasks/test_task_interfaces.py
index a235e589..a2affeb1 100644
--- a/tests/tasks/tasks/test_task_interfaces.py
+++ b/tests/tasks/tasks/test_task_interfaces.py
@@ -11,7 +11,7 @@
 """
 import pytest
 
-from atom.api import Bool, Unicode, set_default
+from atom.api import Bool, Str, set_default
 
 from exopy.tasks.tasks.base_tasks import ComplexTask, RootTask
 from exopy.tasks.tasks.validators import Feval
@@ -53,10 +53,10 @@ class InterfaceTest2(TaskInterface):
 
     """
     #: Member to test auto formatting of tagged members.
-    fmt = Unicode().tag(fmt=True)
+    fmt = Str().tag(fmt=True)
 
     #: Member to test auto evaluation of tagged members.
-    feval = Unicode().tag(feval=Feval())
+    feval = Str().tag(feval=Feval())
 
     database_entries = set_default({'fmt': '', 'feval': 0, 'itest': 2.0})
 
@@ -66,10 +66,10 @@ class InterfaceTest2bis(TaskInterface):
 
     """
     #: Member to test auto formatting of tagged members.
-    fmt = Unicode().tag(fmt=True)
+    fmt = Str().tag(fmt=True)
 
     #: Member to test auto evaluation of tagged members.
-    feval = Unicode().tag(feval=object())
+    feval = Str().tag(feval=object())
 
     database_entries = set_default({'fmt': '', 'feval': 0, 'itest': 2.0})
 
@@ -122,10 +122,10 @@ class IIinterfaceTest2(IInterface):
 
     """
     #: Member to test auto formatting of tagged members.
-    fmt = Unicode().tag(fmt=True)
+    fmt = Str().tag(fmt=True)
 
     #: Member to test auto evaluation of tagged members.
-    feval = Unicode().tag(feval=Feval())
+    feval = Str().tag(feval=Feval())
 
     database_entries = set_default({'fmt': '', 'feval': 0, 'itest': 2.0})
 
diff --git a/tests/tasks/tasks/test_validators.py b/tests/tasks/tasks/test_validators.py
index ebbda2e9..b585d77c 100644
--- a/tests/tasks/tasks/test_validators.py
+++ b/tests/tasks/tasks/test_validators.py
@@ -14,7 +14,7 @@
 from multiprocessing import Event
 
 import pytest
-from atom.api import Unicode
+from atom.api import Str
 
 from exopy.tasks.api import RootTask, validators
 from exopy.tasks.tasks.logic.loop_task import LoopTask
@@ -30,7 +30,7 @@ class Tester(CheckTask):
         """Class for testing feval validators.
 
         """
-        feval = Unicode()
+        feval = Str()
 
     root = RootTask(should_stop=Event(), should_pause=Event())
     task = Tester(name='test', database_entries={'val': 1})
diff --git a/tests/utils/plugin_tools_testing.enaml b/tests/utils/plugin_tools_testing.enaml
index 5f444a63..a406c154 100644
--- a/tests/utils/plugin_tools_testing.enaml
+++ b/tests/utils/plugin_tools_testing.enaml
@@ -9,7 +9,7 @@
 """Manifests used when testing plugin tools module content.
 
 """
-from  atom.api import Typed, Unicode, Bool, Enum
+from  atom.api import Typed, Str, Bool, Enum
 from enaml.workbench.api import (PluginManifest, Plugin, Extension,
                                  ExtensionPoint)
 from  enaml.core.api import Declarative, d_, d_func
@@ -30,9 +30,9 @@ class Contribution(Declarative):
     """Dummy class representing a contribution to an extension point.
 
     """
-    id = d_(Unicode())
+    id = d_(Str())
 
-    description = d_(Unicode())
+    description = d_(Str())
 
     @d_func
     def new(self, workbench):
@@ -168,7 +168,7 @@ class TestDeclarator(Declarator):
     """Dummy Declarator simply taking note that it registered and unregistered.
 
     """
-    id = d_(Unicode())
+    id = d_(Str())
 
     fail_register = d_(Bool())
 
diff --git a/tests/utils/test_atom_util.py b/tests/utils/test_atom_util.py
index 10e11092..43914f2d 100644
--- a/tests/utils/test_atom_util.py
+++ b/tests/utils/test_atom_util.py
@@ -12,7 +12,7 @@
 from collections import OrderedDict
 
 import pytest
-from atom.api import (Unicode, Float, Enum, List, Typed, Int, Value,
+from atom.api import (Str, Float, Enum, List, Typed, Int, Value,
                       Constant)
 from exopy.utils.atom_util import (tagged_members, member_from_pref,
                                    member_to_pref, HasPrefAtom,
@@ -32,7 +32,7 @@ class _Faux(HasPrefAtom):
 
 class _Aux(HasPrefAtom):
 
-    string = Unicode().tag(pref=True)
+    string = Str().tag(pref=True)
     float_n = Float().tag(pref=True)
     enum = Enum('a', 'b').tag(pref=True)
     enum_float = Enum(1.0, 2.0).tag(pref=True)
diff --git a/tests/utils/widgets/test_autoscroll_html.enaml b/tests/utils/widgets/test_autoscroll_html.enaml
index 7e23e885..34765a5c 100644
--- a/tests/utils/widgets/test_autoscroll_html.enaml
+++ b/tests/utils/widgets/test_autoscroll_html.enaml
@@ -16,7 +16,7 @@ in two should be bold.
 """
 import sys
 import os
-from atom.api import Atom, Unicode
+from atom.api import Atom, Str
 from enaml.widgets.api import Window, Container, PushButton
 from enaml.layout.api import vbox, hbox
 
@@ -33,7 +33,7 @@ class Model(Atom):
     """Dummy class holding the string displayed by the QtAutoscrollHtml widget.
 
     """
-    text = Unicode()
+    text = Str()
 
 
 enamldef Main(Window):
diff --git a/tests/utils/widgets/test_completers.enaml b/tests/utils/widgets/test_completers.enaml
index 0e7bccb8..b263a1a5 100644
--- a/tests/utils/widgets/test_completers.enaml
+++ b/tests/utils/widgets/test_completers.enaml
@@ -24,7 +24,7 @@ The window is divided in two :
 """
 import sys
 import os
-from atom.api import Atom, Unicode, Bool
+from atom.api import Atom, Str, Bool
 from enaml.widgets.api import (Window, Container, PushButton, Field,
                                MultilineField, GroupBox)
 from enaml.layout.api import vbox, hbox, spacer
@@ -45,7 +45,7 @@ class Model(Atom):
 
     """
     #: Text displayed by the completer.
-    text = Unicode()
+    text = Str()
 
     #: Flag used to change the proposed list of entries.
     _flag = Bool()
diff --git a/tests/utils/widgets/test_dict_tree_view.enaml b/tests/utils/widgets/test_dict_tree_view.enaml
index b102d036..2501c0de 100644
--- a/tests/utils/widgets/test_dict_tree_view.enaml
+++ b/tests/utils/widgets/test_dict_tree_view.enaml
@@ -11,7 +11,7 @@
 """
 import sys
 import os
-from atom.api import Atom, Unicode, Signal, List
+from atom.api import Atom, Str, Signal, List
 from enaml.widgets.api import (Window, Container, Label, MultilineField)
 from enaml.layout.api import vbox, hbox, spacer
 from enaml.stdlib.mapped_view import MappedView
diff --git a/tests/utils/widgets/test_tree_widget.enaml b/tests/utils/widgets/test_tree_widget.enaml
index 7f89cab4..13bb1a91 100644
--- a/tests/utils/widgets/test_tree_widget.enaml
+++ b/tests/utils/widgets/test_tree_widget.enaml
@@ -40,7 +40,7 @@ Action to test:
 """
 import sys
 import os
-from atom.api import Atom, Unicode, Signal, List
+from atom.api import Atom, Str, Signal, List
 from enaml.widgets.api import (Window, Container, PushButton, Field,
                                CheckBox, Action, GroupBox, Dialog,
                                Menu, Label)
@@ -72,14 +72,14 @@ class File(Atom):
     """Class simply holding a name, to be represented as a leaf.
 
     """
-    name = Unicode()
+    name = Str()
 
 
 class Folder(Atom):
     """Class having a name and children to be represented as a node.
 
     """
-    name = Unicode()
+    name = Str()
 
     children = List()