diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 466536a8..1bb2d41a 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -9,13 +9,16 @@ on:
       - main
     paths:
       - 'constructor-manager/**'
-      - 'constructor-manager-cli/**'
+      - 'constructor-manager-api/**'
   workflow_dispatch:
 
 jobs:
   test:
     name: ${{ matrix.platform }} py${{ matrix.python-version }}
     runs-on: ${{ matrix.platform }}
+    defaults:
+      run:
+        shell: bash -el {0}
     strategy:
       matrix:
         platform: [ubuntu-latest, windows-latest, macos-latest]
@@ -25,36 +28,49 @@ jobs:
       - uses: actions/checkout@v3
 
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v4
+        uses: conda-incubator/setup-miniconda@v2
         with:
-          python-version: ${{ matrix.python-version }}
+          activate-environment: ""
+          auto-activate-base: true
 
-      - name: Install dependencies constructor-manager-cli
+      - name: Install dependencies on main environment
         run: |
-          python -m pip install --upgrade pip
-          python -m pip install setuptools tox tox-gh-actions
-          cd constructor-manager-cli
-          pip install -e .
-          pip list
+          conda install -n base conda-lock mamba -y -c conda-forge
+          conda list
 
-      - name: Test constructor-manager-cli
+      - name: create constructor-manager-environment
         run: |
-          cd constructor-manager-cli
-          python -m tox
-        env:
-          PLATFORM: ${{ matrix.platform }}
+          conda create -n constructor-manager conda packaging requests pyyaml -y -c conda-forge
+          conda activate constructor-manager
+          # List installed packages
+          conda list
 
-      - name: Install dependencies constructor-manager
+      - name: Install constructor-manager
         run: |
-          cd constructor-manager-cli
-          pip install -e .
-          pip list
-        env:
-          PLATFORM: ${{ matrix.platform }}
+          conda activate constructor-manager
+          # Install constructor manager
+          git clone https://github.com/goanpeca/packaging.git packaging_clone
+          cd packaging_clone
+          git checkout constructor-updater
+          cd constructor-manager
+          pip install -e . --no-deps
+          # Install test deps
+          conda install -n constructor-manager pytest pytest-cov pytest-qt -c conda-forge -y
+          # List installed packages
+          conda list
 
-      - name: Test constructor-manager
+      - name: Install constructor-manager-api
         run: |
-          cd constructor-manager
-          python -m tox
-        env:
-          PLATFORM: ${{ matrix.platform }}
+          conda activate constructor-manager
+          conda install -n constructor-manager qtpy pyqt -y -c conda-forge
+          cd constructor-manager-api
+          pip install -e . --no-deps
+
+      - name: Test constructor-manager-api
+        run: |
+          conda activate constructor-manager
+          # List installed packages
+          conda list
+          cd constructor-manager-api/src
+          # Run Tests
+          pytest constructor_manager_api --cov=constructor_manager_api
diff --git a/constructor-manager/LICENSE b/constructor-manager-api/LICENSE
similarity index 100%
rename from constructor-manager/LICENSE
rename to constructor-manager-api/LICENSE
diff --git a/constructor-manager/MANIFEST.in b/constructor-manager-api/MANIFEST.in
similarity index 100%
rename from constructor-manager/MANIFEST.in
rename to constructor-manager-api/MANIFEST.in
diff --git a/constructor-manager-api/README.md b/constructor-manager-api/README.md
new file mode 100644
index 00000000..3586b69c
--- /dev/null
+++ b/constructor-manager-api/README.md
@@ -0,0 +1,64 @@
+# Constructor manager API
+
+## Requirements
+
+- qtpy
+- constructor-manager-cli (on base environment)
+
+## Usage
+
+```python
+from constructor_manager_api.api import check_updates
+
+
+def finished(result):
+    print(result)
+
+
+worker = check_updates(package_name="napari", current_version="0.4.10", channels=[]"conda-forge"])
+worker.finished.connect(finished)
+worker.start()
+```
+
+## Other examples
+
+```python
+import sys
+
+from qtpy.QtCore import QCoreApplication, QTimer  # type: ignore
+
+from constructor_manager_api.api import open_manager
+
+
+def _finished(res):
+    print("This is the result", res)
+
+
+if __name__ == "__main__":
+    app = QCoreApplication([])
+
+    # Process the event loop
+    timer = QTimer()
+    timer.timeout.connect(lambda: None)  # type: ignore
+    timer.start(100)
+
+    worker = check_updates(
+        "napari",
+        current_version="0.4.15",
+        channel="napari",
+        dev=True,
+    )
+    worker = check_updates(
+        "napari",
+        build_string="pyside",
+        plugins_url="https://api.napari-hub.org/plugins",
+    )
+    worker = check_version("napari")
+    worker.finished.connect(_finished)
+    worker.start()
+    sys.exit(app.exec_())
+```
+
+## License
+
+Distributed under the terms of the MIT license. is free and open source software
diff --git a/constructor-manager/pyproject.toml b/constructor-manager-api/pyproject.toml
similarity index 100%
rename from constructor-manager/pyproject.toml
rename to constructor-manager-api/pyproject.toml
diff --git a/constructor-manager/setup.cfg b/constructor-manager-api/setup.cfg
similarity index 81%
rename from constructor-manager/setup.cfg
rename to constructor-manager-api/setup.cfg
index ff2e8e31..13818da1 100644
--- a/constructor-manager/setup.cfg
+++ b/constructor-manager-api/setup.cfg
@@ -1,12 +1,12 @@
 [metadata]
-name = constructor-manager
-version = 0.0.1
-description = Constructor environment and updates manager API
+name = constructor-manager-api
+version = 0.1.0
+description = TODO
 long_description = file: README.md
 long_description_content_type = text/markdown
-url = https://github.com/napari/packaging/constructor-manager
-author = napari team
-author_email = napari-steering-council@googlegroups.com
+url = https://github.com/napari/packaging/constructor-manager-api
+author = napari
+author_email = TODO
 license = MIT
 license_files = LICENSE
 classifiers =
@@ -23,11 +23,12 @@ classifiers =
     Topic :: Scientific/Engineering :: Image Processing
 project_urls =
     Bug Tracker = https://github.com/napari/packaging/issues
-    Source Code = https://github.com/napari/packaging/constructor-manager
+    Source Code = https://github.com/napari/packaging/constructor-manager-api
 
 [options]
 packages = find:
 install_requires =
+    pyyaml
     qtpy
 python_requires = >=3.8
 include_package_data = True
diff --git a/constructor-manager-api/src/constructor_manager_api/__init__.py b/constructor-manager-api/src/constructor_manager_api/__init__.py
new file mode 100644
index 00000000..e9bca1b2
--- /dev/null
+++ b/constructor-manager-api/src/constructor_manager_api/__init__.py
@@ -0,0 +1,2 @@
+VERSION_INFO = (0, 1, 0)
+__version__ = "0.1.0"
diff --git a/constructor-manager-api/src/constructor_manager_api/api.py b/constructor-manager-api/src/constructor_manager_api/api.py
new file mode 100644
index 00000000..52fecfe7
--- /dev/null
+++ b/constructor-manager-api/src/constructor_manager_api/api.py
@@ -0,0 +1,476 @@
+"""Constructor manager api."""
+
+from enum import Enum
+from typing import List, Optional
+import logging
+
+from constructor_manager_api.defaults import DEFAULT_CHANNEL
+from constructor_manager_api.utils.worker import ConstructorManagerWorker
+from constructor_manager_api.utils.conda import get_prefix_by_name
+from constructor_manager_api.utils.settings import save_settings
+
+from qtpy.QtCore import QProcess
+
+
+logger = logging.getLogger(__name__)
+
+
+class ActionsEnum(str, Enum):
+    check_updates = "check-updates"
+    check_version = "check-version"
+    check_packages = "check-packages"
+    update = "update"
+    lock_environment = "lock-environment"
+    restore = "restore"
+    revert = "revert"
+    reset = "reset"
+    open = "open"
+
+
+def _run_action(
+    cmd: ActionsEnum,
+    package_name: Optional[str] = None,
+    version: Optional[str] = None,
+    build_string: Optional[str] = None,
+    channels: Optional[List[str]] = None,
+    dev: bool = False,
+    plugins_url: Optional[str] = None,
+    target_prefix: Optional[str] = None,
+    delayed: bool = False,
+    state: Optional[str] = None,
+) -> ConstructorManagerWorker:
+    """Run constructor action.
+
+    Parameters
+    ----------
+    cmd : ActionsEnum
+        Action to run.
+    package_name : str, optional
+        Name of the package to execute action on.
+    version : str, optional
+        Version of package to execute action on, by default ``None``.
+        If not provided the latest version found will be used.
+    channels : list of str, optional
+        Channel to check for updates, by default ``[DEFAULT_CHANNEL]``.
+    plugins : List[str], optional
+        List of plugins to install, by default ``None``.
+    dev : bool, optional
+        Check for development version, by default ``False``.
+    target_prefix : str, optional
+        Target prefix to install package to, by default ``None``.
+    delayed : bool, optional
+        Delay execution of action, by default ``False``.
+    state : str, optional
+        State to restore, by default ``None``.
+
+    Returns
+    -------
+    ConstructorManagerWorker
+        Worker to check for updates. Includes a finished signal that returns
+        a ``dict`` with the result.
+    """
+    args = [cmd.value]
+    if version is None:
+        version = "*"
+
+    spec = f"{package_name}={version}"
+
+    if build_string is not None:
+        spec += f"=*{build_string}*"
+
+    if package_name is not None and version is not None:
+        args.extend([spec])
+        if channels:
+            for channel in channels:
+                args.extend(["--channel", channel])
+
+    if plugins_url:
+        args.append("--plugins-url")
+        args.append(plugins_url)
+
+    if dev:
+        args.extend(["--dev"])
+
+    if target_prefix:
+        args.append("--target-prefix")
+        args.append(target_prefix)
+
+    if delayed:
+        args.append("--delayed")
+
+    if state:
+        args.append("--state")
+        args.append(state)
+
+    detached = cmd != "status"
+    detached = False
+
+    log_level = logging.getLevelName(logger.getEffectiveLevel())
+    args.extend(["--log", log_level])
+    logger.debug("Running: constructor-manager %s", " ".join(args))
+    return ConstructorManagerWorker(args, detached=detached)
+
+
+def check_updates(
+    package_name: str,
+    current_version: Optional[str] = None,
+    build_string: Optional[str] = None,
+    channels: List[str] = [
+        DEFAULT_CHANNEL,
+    ],
+    dev: bool = False,
+) -> ConstructorManagerWorker:
+    """Check for updates.
+
+    Parameters
+    ----------
+    package_name : str
+        Name of the package to check for updates.
+    current_version : str, optional
+        Current version of the package. If ``None`` the latest version found
+        will be used.
+    build_string: str, optional
+        Build string of the package.
+    channels : list of str, optional
+        Channels to check for updates, by default ``[DEFAULT_CHANNEL]``.
+    dev : bool, optional
+        Check for development version, by default ``False``.
+
+    Returns
+    -------
+    ConstructorManagerWorker
+        Worker to check for updates. Includes a finished signal that returns
+        a ``dict`` with the result.
+    """
+    return _run_action(
+        ActionsEnum.check_updates,
+        package_name,
+        version=current_version,
+        build_string=build_string,
+        channels=channels,
+        dev=dev,
+    )
+
+
+def check_version(package_name: str) -> ConstructorManagerWorker:
+    """Check for version.
+
+    Parameters
+    ----------
+    package_name : str
+        Name of the package to check for updates.
+
+    Returns
+    -------
+    ConstructorManagerWorker
+        Worker to check for the current version insytalled.
+    """
+    return _run_action(ActionsEnum.check_version, package_name)
+
+
+def check_packages(
+    package_name: str,
+    version: Optional[str] = None,
+    plugins_url: Optional[str] = None,
+) -> ConstructorManagerWorker:
+    """Check for updates.
+
+    Parameters
+    ----------
+    package_name : str
+        Name of the package to check for updates.
+    version : str
+        Version of package to execute action on, by default ``None``.
+    plugins_url : str, optional
+        URL to plugins provided by the application as a list of dicts.
+        Keys will be used to filter out packages that are plugins of the
+        application.
+
+    Returns
+    -------
+    ConstructorManagerWorker
+        Worker to check for updates. Includes a finished signal that returns
+        a ``dict`` with the result.
+    """
+    return _run_action(
+        ActionsEnum.check_packages,
+        package_name,
+        version=version,
+        plugins_url=plugins_url,
+    )
+
+
+def update(
+    package_name: str,
+    current_version: str,
+    build_string: Optional[str] = None,
+    channels: Optional[List[str]] = None,
+    plugins_url: Optional[str] = None,
+    dev: bool = False,
+    delayed: bool = False,
+) -> ConstructorManagerWorker:
+    """Update the package to given version.
+
+    If version is None update to latest version found.
+
+    Parameters
+    ----------
+    package_name : str
+        Name of the package to update.
+    current_version : str
+        Current version of the package to update. This is not the version to
+        update to.
+    build_string: str, optional
+        Build string of the package. For example `'*pyside*`'.
+    channels : list of str, optional
+        Conda channels to check for updates.
+    dev : bool, optional
+        Check for development versions of the package, by default ``False``.
+    delayed : bool, optional
+        Delay execution of action, by default ``False``. Useful when running
+        from the main application in the background, instead of using the
+        constructor manager UI.
+
+    Returns
+    -------
+    ConstructorManagerWorker
+        Worker to check for updates. Includes a finished signal that returns
+        a ``dict`` with the result.
+    """
+    return _run_action(
+        ActionsEnum.update,
+        package_name,
+        current_version,
+        build_string=build_string,
+        channels=channels,
+        dev=dev,
+        delayed=delayed,
+        plugins_url=plugins_url,
+    )
+
+
+def restore(
+    package_name: str,
+    current_version: str,
+    state: str,
+    channels: Optional[List[str]] = None,
+    dev: bool = False,
+) -> ConstructorManagerWorker:
+    """Restore to a given saved state within the current version.
+
+    Parameters
+    ---------
+    package_name : str
+        Name of the package to check for updates.
+    current_version : str, optional
+        Version to rollback to, by default ``None``.
+    state : str
+        State to restore to.
+    channel : str, optional
+        Channel to check for updates, by default ``DEFAULT_CHANNEL``.
+    dev : bool, optional
+        Check for development versions, by default ``False``.
+
+    Returns
+    -------
+    ConstructorManagerWorker
+        Worker to check for updates. Includes a finished signal that returns
+        a ``dict`` with the result.
+    """
+    return _run_action(
+        ActionsEnum.restore,
+        package_name,
+        version=current_version,
+        channels=channels,
+        dev=dev,
+        state=state,
+    )
+
+
+def revert(
+    package_name: str,
+    current_version: Optional[str],
+    channels: Optional[List[str]] = None,
+    dev: bool = False,
+) -> ConstructorManagerWorker:
+    """Revert to a previous version state of the current package.
+
+    Parameters
+    ---------
+    package_name : str
+        Name of the package to check for updates.
+    current_version : str, optional
+        Current version of the package to revert.
+    channels : str, optional
+        Channel to check for updates, by default ``DEFAULT_CHANNEL``.
+    dev : bool, optional
+        Check for development version, by default ``False``.
+
+    Returns
+    -------
+    ConstructorManagerWorker
+        Worker to check for updates. Includes a finished signal that returns
+        a ``dict`` with the result.
+    """
+    return _run_action(
+        ActionsEnum.revert,
+        package_name,
+        version=current_version,
+        channels=channels,
+        dev=dev,
+    )
+
+
+def reset(
+    package_name: str,
+    current_version: Optional[str],
+    channels: Optional[List[str]] = None,
+    dev: bool = False,
+) -> ConstructorManagerWorker:
+    """Reset an environment from scratch.
+
+    This will remove all packages and reinstall the current version
+    of the package.
+
+    Parameters
+    ---------
+    package_name : str
+        Name of the package to check for updates.
+    version : str, optional
+        Version to rollback to, by default ``None``.
+    channel : str, optional
+        Channel to check for updates, by default ``DEFAULT_CHANNEL``.
+    dev : bool, optional
+        Check for development version, by default ``False``.
+
+    Returns
+    -------
+    ConstructorManagerWorker
+        Worker to check for updates. Includes a finished signal that returns
+        a ``dict`` with the result.
+    """
+    return _run_action(
+        ActionsEnum.reset,
+        package_name,
+        version=current_version,
+        channels=channels,
+        dev=dev,
+    )
+
+
+def lock_environment(
+    package_name: str,
+    current_version: Optional[str],
+    plugins_url: Optional[str] = None,
+) -> ConstructorManagerWorker:
+    """Generate a lock state file using conda-lock for the environment
+    with package and version.
+
+    This will generate a state file in the configuration folder, so that
+    the restore command can be used with these checkpoints.
+
+    Parameters
+    ---------
+    package_name : str
+        Name of the package to check for updates.
+    current_version : str, optional
+        Version to rollback to, by default ``None``.
+    plugins_url : str, optional
+        URL to the plugins to install, by default ``None``.
+
+    Returns
+    -------
+    ConstructorManagerWorker
+        Worker to check for updates. Includes a finished signal that returns
+        a ``dict`` with the result.
+    """
+    return _run_action(
+        ActionsEnum.lock_environment,
+        package_name,
+        version=current_version,
+        plugins_url=plugins_url,
+    )
+
+
+def open_manager(
+    package_name: str,
+    current_version: Optional[str] = None,
+    plugins_url: Optional[str] = None,
+    build_string: Optional[str] = None,
+    channels: Optional[List[str]] = None,
+    dev: bool = False,
+    log: Optional[str] = None,
+) -> bool:
+    """
+    Open the constructor manager.
+
+    Parameters
+    ----------
+    package_name : str
+        Name of the package to check for updates.
+    current_version : str, optional
+        Current version of the package. If ``None`` the latest version found
+        will be used.
+    build_string: str, optional
+        Build string of the package.
+    channels : list of str, optional
+        Channels to check for updates, by default ``None``.
+    dev : bool, optional
+        Check for development version, by default ``False``.
+    """
+    envs = ["_constructor-manager", "constructor-manager", "base"]
+    for env in envs:
+        target_prefix = get_prefix_by_name(env)
+        path = target_prefix / "bin" / "constructor-manager-ui"
+        if path.exists():
+            break
+
+    settings = {}
+
+    args = [package_name]
+    if current_version:
+        settings["current_version"] = current_version
+
+    if plugins_url:
+        settings["plugins_url"] = plugins_url
+
+    if build_string:
+        settings["build_string"] = build_string
+
+    if dev:
+        settings["dev"] = dev  # type: ignore
+
+    if channels:
+        settings["channels"] = channels  # type: ignore
+
+    if log:
+        settings["log"] = log  # type: ignore
+
+    save_settings(package_name, settings)
+    # TODO: For a separate PR, use open_application when the convention
+    # for applications using constructor nanager is defined in the bundle
+    # workflow
+    return QProcess.startDetached(
+        str(path),
+        args,
+    )
+
+
+def open_application(package_name: str, version: str, target_prefix=None):
+    """Open the application name for given version in a specific prefix.
+
+    Parameters
+    ----------
+    package_name : str
+        Name of the package to check for updates.
+    version : str
+        Version to open.
+    target_prefix : str, optional
+        Target prefix to open the application in, by default ``None``.
+    """
+    return _run_action(
+        ActionsEnum.open,
+        package_name,
+        version=version,
+        target_prefix=target_prefix,
+    )
diff --git a/constructor-manager-api/src/constructor_manager_api/defaults.py b/constructor-manager-api/src/constructor_manager_api/defaults.py
new file mode 100644
index 00000000..de3e7b90
--- /dev/null
+++ b/constructor-manager-api/src/constructor_manager_api/defaults.py
@@ -0,0 +1,3 @@
+"""Defaults and constants."""
+
+DEFAULT_CHANNEL = "conda-forge"
diff --git a/constructor-manager-api/src/constructor_manager_api/run.py b/constructor-manager-api/src/constructor_manager_api/run.py
new file mode 100644
index 00000000..a6b7853d
--- /dev/null
+++ b/constructor-manager-api/src/constructor_manager_api/run.py
@@ -0,0 +1,45 @@
+"""Constructor updater api run tester."""
+
+import sys
+
+from qtpy.QtCore import QCoreApplication, QTimer  # type: ignore
+
+from constructor_manager_api.api import open_manager
+
+
+def _finished(res):
+    print("This is the result", res)
+
+
+if __name__ == "__main__":
+    app = QCoreApplication([])
+
+    # Process the event loop
+    timer = QTimer()
+    timer.timeout.connect(lambda: None)  # type: ignore
+    timer.start(100)
+
+    # worker = check_updates(
+    #     "napari",
+    #     current_version="0.4.15",
+    #     channel="napari",
+    #     dev=True,
+    # )
+    # worker = check_updates(
+    #     "napari",
+    #     build_string="pyside",
+    #     plugins_url="https://api.napari-hub.org/plugins",
+    # )
+    # worker = check_version("napari")
+    # worker.finished.connect(_finished)
+    # worker.start()
+
+    process = open_manager(
+        "napari",
+        build_string="pyside",
+        plugins_url="https://api.napari-hub.org/plugins",
+        channels=["napari", "conda-forge"],
+        log="DEBUG",
+    )
+    sys.exit(process)
+    # sys.exit(app.exec_())
diff --git a/constructor-manager/src/constructor_manager/tests/test_main.py b/constructor-manager-api/src/constructor_manager_api/tests/test_main.py
similarity index 50%
rename from constructor-manager/src/constructor_manager/tests/test_main.py
rename to constructor-manager-api/src/constructor_manager_api/tests/test_main.py
index 488bd751..9433d6d4 100644
--- a/constructor-manager/src/constructor_manager/tests/test_main.py
+++ b/constructor-manager-api/src/constructor_manager_api/tests/test_main.py
@@ -1,7 +1,7 @@
 """Constructor manager API."""
 
-import constructor_manager
+import constructor_manager_api
 
 
 def test_constructor_manager():
-    assert constructor_manager
+    assert constructor_manager_api
diff --git a/constructor-manager-api/src/constructor_manager_api/utils/__init__.py b/constructor-manager-api/src/constructor_manager_api/utils/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/constructor-manager-api/src/constructor_manager_api/utils/_tests/test_worker.py b/constructor-manager-api/src/constructor_manager_api/utils/_tests/test_worker.py
new file mode 100644
index 00000000..bb4feed7
--- /dev/null
+++ b/constructor-manager-api/src/constructor_manager_api/utils/_tests/test_worker.py
@@ -0,0 +1,5 @@
+from constructor_manager_api.utils.conda import get_base_prefix
+
+
+def test_worker():
+    assert get_base_prefix()
diff --git a/constructor-manager-api/src/constructor_manager_api/utils/conda.py b/constructor-manager-api/src/constructor_manager_api/utils/conda.py
new file mode 100644
index 00000000..f0ed45cf
--- /dev/null
+++ b/constructor-manager-api/src/constructor_manager_api/utils/conda.py
@@ -0,0 +1,47 @@
+"""Conda utilities."""
+
+import sys
+from pathlib import Path
+from typing import Optional
+
+
+def get_base_prefix() -> Path:
+    """Get base conda prefix.
+
+    Returns
+    -------
+    pathlib.Path
+        Base conda prefix.
+    """
+    current = Path(sys.prefix)
+    if (current / "envs").exists() and (current / "envs").is_dir():
+        return current
+
+    if current.parent.name == "envs" and current.parent.is_dir():
+        return current.parent.parent
+
+    return current
+
+
+def get_prefix_by_name(name: Optional[str] = None) -> Path:
+    """Get conda prefix by environment name.
+
+    This does not check if the environment exists.
+
+    Parameters
+    ----------
+    name : str, optional
+        Name of the environment. If `None` then return the current prefix.
+
+    Returns
+    -------
+    pathlib.Path
+        Conda prefix for the corresponding ``name``.
+    """
+    base_prefix = get_base_prefix()
+    if name is None:
+        return Path(sys.prefix)
+    elif name == "base":
+        return base_prefix
+    else:
+        return base_prefix / "envs" / name
diff --git a/constructor-manager-api/src/constructor_manager_api/utils/io.py b/constructor-manager-api/src/constructor_manager_api/utils/io.py
new file mode 100644
index 00000000..ee1fb7df
--- /dev/null
+++ b/constructor-manager-api/src/constructor_manager_api/utils/io.py
@@ -0,0 +1,17 @@
+from pathlib import Path
+
+from constructor_manager_api.utils.conda import get_prefix_by_name
+
+
+def get_config_path() -> Path:
+    """Get the path to the constructor-manager-ui config directory."""
+    path = get_prefix_by_name("constructor-manager") / "var" / "constructor-manager-ui"
+    path.mkdir(parents=True, exist_ok=True)
+    return path
+
+
+def get_settings_path(package_name: str) -> Path:
+    """Get the path to the settings file for a package."""
+    path = get_config_path() / "settings" / f"{package_name}.yaml"
+    path.parent.mkdir(parents=True, exist_ok=True)
+    return path
diff --git a/constructor-manager-api/src/constructor_manager_api/utils/settings.py b/constructor-manager-api/src/constructor_manager_api/utils/settings.py
new file mode 100644
index 00000000..da49bdba
--- /dev/null
+++ b/constructor-manager-api/src/constructor_manager_api/utils/settings.py
@@ -0,0 +1,36 @@
+"""Constuctor manager."""
+
+from typing import Any, Dict
+
+import yaml
+
+from constructor_manager_api.utils.io import get_settings_path
+
+
+_default_settings = {  # type: ignore
+    "current_version": None,
+    "build_string": None,
+    "plugins_url": None,
+    "channels": [],
+    "log": None,
+    "dev": None,
+}
+
+
+def save_settings(package_name: str, settings: Dict[str, Any]) -> None:
+    """"Save constructor manager settings to file per `package_name`.""" ""
+    path = get_settings_path(package_name)
+    with open(path, "w") as f:
+        yaml.dump(settings, f)
+
+
+def load_settings(package_name: str):
+    """"Load constructor manager settings from file per `package_name`.""" ""
+    path = get_settings_path(package_name)
+    loaded_settings = _default_settings.copy()
+    if path.exists():
+        with open(path) as f:
+            data = yaml.load(f, Loader=yaml.FullLoader)
+        loaded_settings.update(data)
+
+    return loaded_settings
diff --git a/constructor-manager-api/src/constructor_manager_api/utils/worker.py b/constructor-manager-api/src/constructor_manager_api/utils/worker.py
new file mode 100644
index 00000000..6b09f88f
--- /dev/null
+++ b/constructor-manager-api/src/constructor_manager_api/utils/worker.py
@@ -0,0 +1,110 @@
+"""Constructor updater api worker."""
+
+import json
+import logging
+from typing import List
+
+from qtpy.QtCore import QObject, QProcess, Signal  # type: ignore
+
+from constructor_manager_api.utils.conda import get_prefix_by_name
+
+
+logger = logging.getLogger(__name__)
+
+
+class ConstructorManagerWorker(QObject):
+    """A worker to run the constructor manager cli and process errors.
+
+    Parameters
+    ----------
+    args : list
+        Arguments to pass to the constructor manager.
+    detached : bool, optional
+        Run the process detached, by default ``False``.
+    """
+
+    _WORKERS: "List[ConstructorManagerWorker]" = []
+    finished = Signal(dict)
+
+    def __init__(self, args, detached=False):
+        super().__init__()
+        ConstructorManagerWorker._WORKERS.append(self)
+        self._detached = detached
+        self._program = self._executable()
+
+        if not self._program.is_file():
+            raise FileNotFoundError(f"Could not find {self._program}")
+
+        self._args = args
+        self._process = QProcess()
+        self._process.setArguments(args)
+        self._process.setProgram(str(self._program))
+        self._process.finished.connect(self._finished)
+
+    @staticmethod
+    def _executable():
+        """Get the executable for the constructor manager."""
+        bin = "constructor-manager-cli"
+        envs = ["_constructor-manager", "constructor-manager", "base"]
+        for env in envs:
+            program = get_prefix_by_name(env) / "bin" / bin
+            if program.is_file():
+                return program
+        else:
+            raise FileNotFoundError(
+                f"Could not find {bin} in any of the following environments: {envs}"
+            )
+
+    def _finished(
+        self,
+        exit_code: int,
+        exit_status: QProcess.ExitStatus = QProcess.ExitStatus.NormalExit,
+    ):
+        """Handle the finished signal of the worker and emit results."""
+        logger.debug(
+            "Worker with args `%s` finished with exit code %s and exit status %s",
+            " ".join(self._args),
+            exit_code,
+            exit_status,
+        )
+        try:
+            stdout = self._process.readAllStandardOutput()
+            stderr = self._process.readAllStandardError()
+        except RuntimeError as e:
+            self.finished.emit({"data": {}, "error": str(e)})
+            return
+
+        raw_output = stdout.data().decode()
+        raw_error = stderr.data().decode()
+        error = raw_error
+
+        output = {}
+        if exit_code == 0 and exit_status == QProcess.ExitStatus.NormalExit:
+            try:
+                output = json.loads(raw_output)
+            except Exception:
+                error = raw_output
+
+        data = output.get("data", raw_output)
+        error = error or output.get("error", error)
+        result = {
+            "data": data,
+            "error": error,
+            "exit_code": exit_code,
+            "exit_status": exit_status,
+        }
+        self.finished.emit(result)
+
+    def state(self):
+        """State of the worker."""
+        return self._process.state()
+
+    def start(self):
+        """Start the worker."""
+        logger.debug("Worker with args `%s` started!", " ".join(self._args))
+        self._process.startDetached() if self._detached else self._process.start()
+
+    def terminate(self):
+        """Terminate the process worker."""
+        logger.debug("Worker with args `%s` terminated!", " ".join(self._args))
+        self._process.terminate()
diff --git a/constructor-manager/tox.ini b/constructor-manager-api/tox.ini
similarity index 95%
rename from constructor-manager/tox.ini
rename to constructor-manager-api/tox.ini
index b1f09aa6..f73994ab 100644
--- a/constructor-manager/tox.ini
+++ b/constructor-manager-api/tox.ini
@@ -23,7 +23,8 @@ platform =
 passenv =
     CI
     GITHUB_ACTIONS
-    DISPLAY XAUTHORITY
+    DISPLAY
+    XAUTHORITY
     NUMPY_EXPERIMENTAL_ARRAY_FUNCTION
     PYVISTA_OFF_SCREEN
 extras =
diff --git a/constructor-manager/README.md b/constructor-manager/README.md
deleted file mode 100644
index 96c8c0b9..00000000
--- a/constructor-manager/README.md
+++ /dev/null
@@ -1,3 +0,0 @@
-# Constructor manager
-
-TODO
diff --git a/constructor-manager/src/constructor_manager/__init__.py b/constructor-manager/src/constructor_manager/__init__.py
deleted file mode 100644
index d05157c8..00000000
--- a/constructor-manager/src/constructor_manager/__init__.py
+++ /dev/null
@@ -1,3 +0,0 @@
-"""Constructor manager API."""
-
-__version__ = "0.0.1"